235 results on '"Fenice, Massimiliano"'
Search Results
52. The Psychrotolerant Antarctic Fungus Lecanicillium muscarium CCFEE 5003: A Powerful Producer of Cold-Tolerant Chitinolytic Enzymes
- Author
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Fenice, Massimiliano, primary
- Published
- 2016
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53. Mapping the lithic colonization at the boundaries of life in Northern Victoria Land, Antarctica
- Author
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Zucconi, Laura, primary, Onofri, Silvano, additional, Cecchini, Clarissa, additional, Isola, Daniela, additional, Ripa, Caterina, additional, Fenice, Massimiliano, additional, Madonna, Sergio, additional, Reboleiro-Rivas, Patricia, additional, and Selbmann, Laura, additional
- Published
- 2014
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54. Plant growth enhancement by biotechnological tools
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Vassileva, Maria, primary, Fenice, Massimiliano, additional, Galvez, Antonia, additional, and Vassilev, Nikolay, additional
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- 2014
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55. Bacterial community structure of a coastal area in Kandalaksha Bay, White Sea, Russia: possible relation to tidal hydrodynamics
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Pesciaroli, Chiara, primary, Rodelas, Belén, additional, Juarez-Jiménez, Belén, additional, Barghini, Paolo, additional, and Fenice, Massimiliano, additional
- Published
- 2014
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- View/download PDF
56. Biotreatment of olive washing wastewater by a selected microalgal-bacterial consortium
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Maza-Márquez, Paula, primary, Martinez-Toledo, María Victoria, additional, Fenice, Massimiliano, additional, Andrade, Luis, additional, Lasserrot, A., additional, and Gonzalez-Lopez, Jesús, additional
- Published
- 2014
- Full Text
- View/download PDF
57. Corrigendum to “High production of cold-tolerant chitinases on shrimp wastes in bench-top bioreactor by the Antarctic fungus Lecanicillium muscarium CCFEE 5003: Bioprocess optimization and characterization of two main enzymes” [Enzyme Microb. Technol. 53 (5) (2013) 331–338]
- Author
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Barghini, Paolo, primary, Moscatelli, Deborah, additional, Garzillo, Anna Maria Vittoria, additional, Crognale, Silvia, additional, and Fenice, Massimiliano, additional
- Published
- 2013
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- View/download PDF
58. High production of cold-tolerant chitinases on shrimp wastes in bench-top bioreactor by the Antarctic fungus Lecanicillium muscarium CCFEE 5003: Bioprocess optimization and characterization of two main enzymes
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Barghini, Paolo, primary, Moscatelli, Deborah, additional, Garzillo, Anna Maria Vittoria, additional, Crognale, Silvia, additional, and Fenice, Massimiliano, additional
- Published
- 2013
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59. Biodegradation of olive washing wastewater pollutants by highly efficient phenol-degrading strains selected from adapted bacterial community
- Author
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Maza-Márquez, Paula, primary, Martínez-Toledo, Maria Victoria, additional, González-López, Jesús, additional, Rodelas, Belén, additional, Juárez-Jiménez, Belén, additional, and Fenice, Massimiliano, additional
- Published
- 2013
- Full Text
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60. Potential extinction of Antarctic endemic fungal species as a consequence of global warming
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Selbmann, Laura, primary, Isola, Daniela, additional, Fenice, Massimiliano, additional, Zucconi, Laura, additional, Sterflinger, Katja, additional, and Onofri, Silvano, additional
- Published
- 2012
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61. Temperature preferences of bacteria isolated from seawater collected in Kandalaksha Bay, White Sea, Russia
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Pesciaroli, Chiara, primary, Cupini, Francesco, additional, Selbmann, Laura, additional, Barghini, Paolo, additional, and Fenice, Massimiliano, additional
- Published
- 2011
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62. Metabolic characterization of a strain (BM90) of Delftia tsuruhatensis showing highly diversified capacity to degrade low molecular weight phenols
- Author
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Juárez-Jiménez, Belén, primary, Manzanera, Maximino, additional, Rodelas, Belén, additional, Martínez-Toledo, Maria Victoria, additional, Gonzalez-López, Jesus, additional, Crognale, Silvia, additional, Pesciaroli, Chiara, additional, and Fenice, Massimiliano, additional
- Published
- 2009
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63. Production of chitinolytic enzymes by a strain (BM17) of Paenibacillus pabuli isolated from crab shells samples collected in the east sector of central Tyrrhenian Sea
- Author
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Juarez-Jimenez, Belen, primary, Rodelas, Belen, additional, Martinez-Toledo, M. Victoria, additional, Gonzalez-Lopez, Jesus, additional, Crognale, Silvia, additional, Gallo, Anna M., additional, Pesciaroli, Chiara, additional, and Fenice, Massimiliano, additional
- Published
- 2008
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64. Enzyme and fungal treatments and a combination thereof reduce olive mill wastewater phytotoxicity on Zea mays L. seeds
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Quaratino, Daniele, primary, D’Annibale, Alessandro, additional, Federici, Federico, additional, Cereti, Carlo Fausto, additional, Rossini, Francesco, additional, and Fenice, Massimiliano, additional
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- 2007
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65. Production, purification and partial characterisation of a novel laccase from the white-rot fungus Panus tigrinus CBS 577.79
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Quaratino, Daniele, primary, Federici, Federico, additional, Petruccioli, Maurizio, additional, Fenice, Massimiliano, additional, and D’Annibale, Alessandro, additional
- Published
- 2006
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66. Olive oil mill wastewater valorisation by fungi
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Crognale, Silvia, primary, D'Annibale, Alessandro, additional, Federici, Federico, additional, Fenice, Massimiliano, additional, Quaratino, Daniele, additional, and Petruccioli, Maurizio, additional
- Published
- 2006
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67. Mn-peroxidase production byPanus tigrinus CBS 577.79: response surface optimisation and bioreactor comparison
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Quaratino, Daniele, primary, Fenice, Massimiliano, additional, Federici, Federico, additional, and D'Annibale, Alessandro, additional
- Published
- 2006
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68. Repeated-batch production of pigments by immobilised Monascus purpureus
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Fenice, Massimiliano, primary, Federici, Federico, additional, Selbmann, Laura, additional, and Petruccioli, Maurizio, additional
- Published
- 2000
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69. Ecology and biology of microfungi from Antarctic rocks and soils
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Onofri, Silvano, primary, Fenice, Massimiliano, additional, Cicalini, Anna Rita, additional, Tosi, Solveig, additional, Magrino, Anna, additional, Pagano, Sabina, additional, Selbmann, Laura, additional, Zucconi, Laura, additional, Vishniac, Helen S., additional, Ocampo‐Friedmann, Roseli, additional, and Friedmann, E. Imre, additional
- Published
- 2000
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70. Inactivation of Mucor plumbeus by the combined actions of chitinase and high hydrostatic pressure
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Fenice, Massimiliano, primary, Di Giambattista, Roberta, additional, Leuba, Jean-Louis, additional, and Federici, Federico, additional
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- 1999
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71. Repeated-batch and continuous production of chitinolytic enzymes by Penicillium janthinellum immobilised on chemically-modified macroporous cellulose
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Fenice, Massimiliano, primary, Di Giambattista, Roberta, additional, Raetz, Eric, additional, Leuba, Jean-Louis, additional, and Federici, Federico, additional
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- 1998
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72. Chitinolytic enzyme activity of Penicillium janthinellum P9 in bench-top bioreactor
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Fenice, Massimiliano, primary, Leuba, Jean-Louis, additional, and Federici, Federico, additional
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- 1998
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73. Olive mill waster water treatment by immobilized cells of Aspergillus niger and its enrichment with soluble phosphate
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Vassilev, Nikolay, primary, Fenice, Massimiliano, additional, Federici, Federico, additional, and Azcon, Rosario, additional
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- 1997
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74. Effect of stirrer speed and buffering agents on the production of glucose oxidase and catalase by Penicillium variabile (P16) in benchtop bioreactor
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Petruccioli, Maurizio, primary, Fenice, Massimiliano, additional, Piccioni, Paola, additional, and Federici, Federico, additional
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- 1995
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75. Mycoparasitic actions against fungi and oomycetes by a strain (CCFEE 5003) of the fungus Lecanicillium muscarium isolated in Continental Antarctica.
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Fenice, Massimiliano and Gooday, Graham
- Abstract
A strain (CCFEE 5003) of Lecanicillium muscarium, isolated in Continental Antarctica, showed mycoparasitism in agar cocultures, at 5 and 25 °C, against Mucor mucedo, Botrytis cinerea, Pythium aphanidermatum and Phytophthora palmivora. Different sequential steps were observed in the process leading to parasitism and resulting in a complete host disruption. Parasitism against fungi was characterised by diffused penetration into the host mycelium; with oomycetes, penetration was less evident and the contact between the two organisms was more intimate. Production of glucanolytic and chitinolytic enzymes appeared related to the mycoparasitic process. [ABSTRACT FROM AUTHOR]
- Published
- 2006
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76. Microbiological Study in Petrol-Spiked Soil.
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Borowik, Agata, Wyszkowska, Jadwiga, Kucharski, Jan, Fenice, Massimiliano, and Gorrasi, Susanna
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MICROBIAL enzymes ,SOIL composition ,GENETIC variation ,SOIL enzymology ,ENERGY consumption ,BACTERIAL diversity ,SOIL pollution - Abstract
The pollution of arable lands and water with petroleum-derived products is still a valid problem, mainly due the extensive works aimed to improve their production technology to reduce fuel consumption and protect engines. An example of the upgraded fuels is the BP 98 unleaded petrol with Active technology. A pot experiment was carried out in which Eutric Cambisol soil was polluted with petrol to determine its effect on the microbiological and biochemical properties of this soil. Analyses were carried out to determine soil microbiome composition—with the incubation and metagenomic methods, the activity of seven enzymes, and cocksfoot effect on hydrocarbon degradation. The following indices were determined: colony development index (CD); ecophysiological diversity index (EP); index of cocksfoot effect on soil microorganisms and enzymes (IF
G ); index of petrol effect on soil microorganisms and enzymes (IFP ); index of the resistance of microorganisms, enzymes, and cocksfoot to soil pollution with petrol (RS); Shannon–Weaver's index of bacterial taxa diversity (H); and Shannon–Weaver's index of hydrocarbon degradation (IDH ). The soil pollution with petrol was found to increase population numbers of bacteria and fungi, and Protebacteria phylum abundance as well as to decrease the abundance of Actinobacteria and Acidobacteria phyla. The cultivation of cocksfoot on the petrol-polluted soil had an especially beneficial effect mainly on the bacteria belonging to the Ramlibacter, Pseudoxanthomonas, Mycoplana, and Sphingobium genera. The least susceptible to the soil pollution with petrol and cocksfoot cultivation were the bacteria of the following genera: Kaistobacter, Rhodoplanes, Bacillus, Streptomyces, Paenibacillus, Phenylobacterium, and Terracoccus. Cocksfoot proved effective in the phytoremediation of petrol-polluted soil, as it accelerated hydrocarbon degradation and increased the genetic diversity of bacteria. It additionally enhanced the activities of soil enzymes. [ABSTRACT FROM AUTHOR]- Published
- 2021
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77. Role of Bacillus cereus in Improving the Growth and Phytoextractability of Brassica nigra (L.) K. Koch in Chromium Contaminated Soil.
- Author
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Akhtar, Nosheen, Ilyas, Noshin, Yasmin, Humaira, Sayyed, R. Z., Hasnain, Zuhair, A. Elsayed, Elsayed, El Enshasy, Hesham A., Fenice, Massimiliano, and Chrzanowski, Łukasz
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MUSTARD ,PLANT growth ,BACILLUS cereus ,PLANT growth promoting substances ,CHROMIUM ,PLANT growth-promoting rhizobacteria ,PLANT pigments ,INDOLEACETIC acid - Abstract
Plant growth-promoting rhizobacteria (PGPR) mediate heavy metal tolerance and improve phytoextraction potential in plants. The present research was conducted to find the potential of bacterial strains in improving the growth and phytoextraction abilities of Brassica nigra (L.) K. Koch. in chromium contaminated soil. In this study, a total of 15 bacterial strains were isolated from heavy metal polluted soil and were screened for their heavy metal tolerance and plant growth promotion potential. The most efficient strain was identified by 16S rRNA gene sequencing and was identified as Bacillus cereus. The isolate also showed the potential to solubilize phosphate and synthesize siderophore, phytohormones (indole acetic acid, cytokinin, and abscisic acid), and osmolyte (proline and sugar) in chromium (Cr
+3 ) supplemented medium. The results of the present study showed that chromium stress has negative effects on seed germination and plant growth in B. nigra while inoculation of B. cereus improved plant growth and reduced chromium toxicity. The increase in seed germination percentage, shoot length, and root length was 28.07%, 35.86%, 19.11% while the fresh and dry biomass of the plant increased by 48.00% and 62.16%, respectively, as compared to the uninoculated/control plants. The photosynthetic pigments were also improved by bacterial inoculation as compared to untreated stress-exposed plants, i.e., increase in chlorophyll a, chlorophyll b, chlorophyll a + b, and carotenoid was d 25.94%, 10.65%, 20.35%, and 44.30%, respectively. Bacterial inoculation also resulted in osmotic adjustment (proline 8.76% and sugar 28.71%) and maintained the membrane stability (51.39%) which was also indicated by reduced malondialdehyde content (59.53% decrease). The antioxidant enzyme activities were also improved to 35.90% (superoxide dismutase), 59.61% (peroxide), and 33.33% (catalase) in inoculated stress-exposed plants as compared to the control plants. B. cereus inoculation also improved the uptake, bioaccumulation, and translocation of Cr in the plant. Data showed that B. cereus also increased Cr content in the root (2.71-fold) and shoot (4.01-fold), its bioaccumulation (2.71-fold in root and 4.03-fold in the shoot) and translocation (40%) was also high in B. nigra. The data revealed that B. cereus is a multifarious PGPR that efficiently tolerates heavy metal ions (Cr+3 ) and it can be used to enhance the growth and phytoextraction potential of B. nigra in heavy metal contaminated soil. [ABSTRACT FROM AUTHOR]- Published
- 2021
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78. Thermophilic Anaerobic Digestion of Second Cheese Whey: Microbial Community Response to H 2 Addition in a Partially Immobilized Anaerobic Hybrid Reactor.
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Lembo, Giuseppe, Rosa, Silvia, Mazzurco Miritana, Valentina, Marone, Antonella, Massini, Giulia, Fenice, Massimiliano, and Signorini, Antonella
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ANAEROBIC digestion ,ANAEROBIC reactors ,MICROBIAL communities ,WHEY ,CHEESE ,UPFLOW anaerobic sludge blanket reactors ,ARCHAEBACTERIA - Abstract
In this study, we investigated thermophilic (55 °C) anaerobic digestion (AD) performance and microbial community structure, before and after hydrogen addition, in a novel hybrid gas-stirred tank reactor (GSTR) implemented with a partial immobilization of the microbial community and fed with second cheese whey (SCW). The results showed that H
2 addition led to a 25% increase in the methane production rate and to a decrease of 13% in the CH4 concentration as compared with the control. The recovery of methane content (56%) was reached by decreasing the H2 flow rate. The microbial community investigations were performed on effluent (EF) and on interstitial matrix (IM) inside the immobilized area. Before H2 addition, the Anaerobaculaceae (42%) and Lachnospiraceae (27%) families dominated among bacteria in the effluent, and the Thermodesulfobiaceae (32%) and Lachnospiraceae (30%) families dominated in the interstitial matrix. After H2 addition, microbial abundance showed an increase in the bacteria and archaea communities in the interstitial matrix. The Thermodesulfobiaceae family (29%)remained dominant in the interstitial matrix, suggesting its crucial role in the immobilized community and the SHA-31 family was enriched in both the effluent (36%) and the interstitial matrix (15%). The predominance of archaea Methanothermobacter thermoautrophicus indicated that CH4 was produced almost exclusively by the hydrogenotrophic pathway. [ABSTRACT FROM AUTHOR]- Published
- 2021
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79. Occurrence of Biogenic Amines Producers in the Wastewater of the Dairy Industry.
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Jančová, Petra, Pachlová, Vendula, Čechová, Erika, Cedidlová, Karolína, Šerá, Jana, Pištěková, Hana, Buňka, František, Buňková, Leona, Zuorro, Antonio, and Fenice, Massimiliano
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BIOGENIC amines ,DAIRY industry ,SEWAGE ,MICROBACTERIUM ,ENTEROBACTER ,MICROBIAL contamination - Abstract
Out of six samples of wastewater produced in the dairy industry, taken in 2017 at various places of dairy operations, 86 bacterial strains showing decarboxylase activity were isolated. From the wastewater samples, the species of genera Staphylococcus, Lactococcus, Enterococcus, Microbacterium, Kocuria, Acinetobacter, Pseudomonas, Aeromonas, Klebsiella and Enterobacter were identified by the MALDI-TOF MS and biochemical methods. The in vitro produced quantity of eight biogenic amines (BAs) was detected by the HPLC/UV–Vis method. All the isolated bacteria were able to produce four to eight BAs. Tyramine, putrescine and cadaverine belonged to the most frequently produced BAs. Of the isolated bacteria, 41% were able to produce BAs in amounts >100 mg L
−1 . Therefore, wastewater embodies a potential vector of transmission of decarboxylase positive microorganisms, which should be taken into consideration in hazard analyses within foodstuff safety control. The parameters of this wastewater (contents of nitrites, nitrates, phosphates, and proteins) were also monitored. [ABSTRACT FROM AUTHOR]- Published
- 2020
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80. Chitosan Contribution to Therapeutic and Vaccinal Approaches for the Control of Leishmaniasis.
- Author
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Loiseau, Philippe M., Pomel, Sébastien, Croft, Simon L., and Fenice, Massimiliano
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CHITOSAN ,LEISHMANIASIS ,CHAGAS' disease ,CUTANEOUS leishmaniasis ,VISCERAL leishmaniasis ,VACCINE development - Abstract
The control of leishmaniases, a complex parasitic disease caused by the protozoan parasite Leishmania, requires continuous innovation at the therapeutic and vaccination levels. Chitosan is a biocompatible polymer administrable via different routes and possessing numerous qualities to be used in the antileishmanial strategies. This review presents recent progress in chitosan research for antileishmanial applications. First data on the mechanism of action of chitosan revealed an optimal in vitro intrinsic activity at acidic pH, high-molecular-weight chitosan being the most efficient form, with an uptake by pinocytosis and an accumulation in the parasitophorous vacuole of Leishmania-infected macrophages. In addition, the immunomodulatory effect of chitosan is an added value both for the treatment of leishmaniasis and the development of innovative vaccines. The advances in chitosan chemistry allows pharmacomodulation on amine groups opening various opportunities for new polymers of different size, and physico-chemical properties adapted to the chosen routes of administration. Different formulations have been studied in experimental leishmaniasis models to cure visceral and cutaneous leishmaniasis, and chitosan can act as a booster through drug combinations with classical drugs, such as amphotericin B. The various architectural possibilities given by chitosan chemistry and pharmaceutical technology pave the way for promising further developments. [ABSTRACT FROM AUTHOR]
- Published
- 2020
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81. Obtaining and Characterization of the PLA/Chitosan Foams with Antimicrobial Properties Achieved by the Emulsification Combined with the Dissolution of Chitosan by CO2 Saturation.
- Author
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Mania, Szymon, Partyka, Karolina, Pilch, Joanna, Augustin, Ewa, Cieślik, Mateusz, Ryl, Jacek, Jinn, Jia-Rong, Wang, Ya-Jane, Michałowska, Anna, Tylingo, Robert, and Fenice, Massimiliano
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FOAM ,CHITOSAN ,POLYLACTIC acid ,CHEMICAL bonds ,POLYETHYLENE glycol ,LACTIC acid ,ELASTICITY - Abstract
A new method of obtaining functional foam material has been proposed. The materials were created by mixing the poly lactic acid (PLA) solution in chloroform, chitosan (CS) dissolved in water saturated with CO
2 and polyethylene glycol (PEG), and freeze-dried for removal of the solvents. The composite foams were characterized for their structural (SEM, FT-IR, density, porosity), thermal (DSC), functional (hardness, elasticity, swelling capacity, solubility), and biological (antimicrobial and cytotoxic) properties. Chitosan in the composites was a component for obtaining their foamed form with 7.4 to 22.7 times lower density compared to the neat PLA and high porosity also confirmed by the SEM. The foams had a hardness in the range of 70–440 kPa. The FT-IR analysis confirmed no new chemical bonds between the sponge ingredients. Other results showed low sorption capacity (2.5–7.2 g/g) and solubility of materials (less than 0.2%). The obtained foams had the lower Tg value and improved ability of crystallization compared to neat PLA. The addition of chitosan provides the bacteriostatic and bactericidal properties against Escherichia coli and Staphylococcus aureus. Biocompatibility studies have shown that the materials obtained are not cytotoxic to the L929 cell line. [ABSTRACT FROM AUTHOR]- Published
- 2019
- Full Text
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82. Glycol Chitosan: A Water-Soluble Polymer for Cell Imaging and Drug Delivery.
- Author
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Lin, Fengming, Jia, Hao-Ran, Wu, Fu-Gen, and Fenice, Massimiliano
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WATER-soluble polymers ,CELL imaging ,NUCLEIC acids ,ANTI-infective agents ,SURFACES (Technology) ,ETHYLENE glycol ,CHITOSAN - Abstract
Glycol chitosan (GC), a water-soluble chitosan derivative with hydrophilic ethylene glycol branches, has both hydrophobic segments for the encapsulation of various drugs and reactive functional groups for facile chemical modifications. Over the past two decades, a variety of molecules have been physically encapsulated within or chemically conjugated with GC and its derivatives to construct a wide range of functional biomaterials. This review summarizes the recent advances of GC-based materials in cell surface labeling, multimodal tumor imaging, and encapsulation and delivery of drugs (including chemotherapeutics, photosensitizers, nucleic acids, and antimicrobial agents) for combating cancers and microbial infections. Besides, different strategies for GC modifications are also highlighted with the aim to shed light on how to endow GC and its derivatives with desirable properties for therapeutic purposes. In addition, we discuss both the promises and challenges of the GC-derived biomaterials. [ABSTRACT FROM AUTHOR]
- Published
- 2019
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- View/download PDF
83. Dual Insecticidal Effects of Adenanthera pavonina Kunitz-Type Inhibitor on Plodia interpunctella is Mediated by Digestive Enzymes Inhibition and Chitin-Binding Properties.
- Author
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de Oliveira, Caio Fernando Ramalho, de Oliveira Flores, Taylla Michelle, Henrique Cardoso, Marlon, Garcia Nogueira Oshiro, Karen, Russi, Raphael, de França, Anderson Felipe Jácome, dos Santos, Elizeu Antunes, Luiz Franco, Octávio, de Oliveira, Adeliana Silva, Migliolo, Ludovico, and Fenice, Massimiliano
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DIGESTIVE enzymes ,INDIANMEAL moth ,TRYPSIN ,TRYPSIN inhibitors ,PEST control ,MOLECULAR docking - Abstract
The Indianmeal moth, Plodia interpunctella, is one of the most damaging pests of stored products. We investigated the insecticidal properties of ApKTI, a Kunitz trypsin inhibitor from Adenanthera pavonina seeds, against P. interpunctella larvae through bioassays with artificial diet. ApKTI-fed larvae showed reduction of up to 88% on larval weight and 75% in survival. Trypsin enzymes extracted from P. interpunctella larvae were inhibited by ApKTI, which also demonstrated capacity to bind to chitin. Kinetic studies revealed a non-competitive inhibition mechanism of ApKTI for trypsin, which were further corroborated by molecular docking studies. Furthermore, we have demonstrated that ApKTI exhibits a hydrophobic pocket near the reactive site loop probably involved in chitin interactions. Taken together, these data suggested that the insecticidal activity of ApKTI for P. interpunctella larvae involves a dual and promiscuous mechanisms biding to two completely different targets. Both processes might impair the P. interpunctella larval digestive process, leading to larvae death before reaching the pupal stage. Further studies are encouraged using ApKTI as a biotechnological tool to control insect pests in field conditions. [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
- View/download PDF
84. Development-Disrupting Chitin Synthesis Inhibitor, Novaluron, Reprogramming the Chitin Degradation Mechanism of Red Palm Weevils.
- Author
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Hussain, Abid, AlJabr, Ahmed Mohammed, Al-Ayedh, Hassan, and Fenice, Massimiliano
- Subjects
DATE palm ,CHITIN ,CURCULIONIDAE ,GENETIC overexpression ,RED ,PALMS ,BIOLOGICAL assay - Abstract
Disruption in chitin regulation by using chitin synthesis inhibitor (novaluron) was investigated to gain insights into the biological activity of chitinase in red palm weevils, an invasive pest of date palms in the Middle East. Impact of novaluron against ninth instar red palm weevil larvae was examined by dose-mortality response bioassays, nutritional indices, and expression patterns of chitinase genes characterized in this study. Laboratory bioassays revealed dose-dependent mortality response of ninth-instar red palm weevil larvae with LD
50 of 14.77 ppm of novaluron. Dietary growth analysis performed using different doses of novaluron (30, 25, 20, 15, 10, and 5 ppm) exhibited very high reduction in their indexes such as Efficacy of Conversion of Digested Food (82.38%) and Efficacy of Conversion of Ingested Food (74.27%), compared with control treatment. Transcriptomic analysis of red palm weevil larvae characterized numerous genes involved in chitin degradation including chitinase, chitinase-3-like protein 2, chitinase domain-containing protein 1, Endochitinase-like, chitinase 3, and chitin binding peritrophin-a domain. However, quantitative expression patterns of these genes in response to novaluron-fed larvae revealed tissue-specific time-dependent expression patterns. We recorded overexpression of all genes from mid-gut tissues. Growth retarding, chitin remodeling and larvicidal potential suggest novaluron as a promising alternate for Rhynchophorus ferrugineus management. [ABSTRACT FROM AUTHOR]- Published
- 2019
- Full Text
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85. Efficient Removal of Copper Ion from Wastewater Using a Stable Chitosan Gel Material.
- Author
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Yang, Zujin, Chai, Yuxin, Zeng, Lihua, Gao, Zitao, Zhang, Jianyong, Ji, Hongbing, and Fenice, Massimiliano
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COPPER ions ,PHYSISORPTION ,CHITOSAN ,X-ray photoelectron spectroscopy ,PHOTOELECTRON spectroscopy ,LANGMUIR isotherms - Abstract
Gel adsorption is an efficient method for the removal of metal ion. In the present study, a functional chitosan gel material (FCG) was synthesized successfully, and its structure was detected by different physicochemical techniques. The as-prepared FCG was stable in acid and alkaline media. The as-prepared material showed excellent adsorption properties for the capture of Cu
2+ ion from aqueous solution. The maximum adsorption capacity for the FCG was 76.4 mg/g for Cu2+ ion (293 K). The kinetic adsorption data fits the Langmuir isotherm, and experimental isotherm data follows the pseudo-second-order kinetic model well, suggesting that it is a monolayer and the rate-limiting step is the physical adsorption. The separation factor (RL ) for Langmuir and the 1/n value for Freundlich isotherm show that the Cu2+ ion is favorably adsorbed by FCG. The negative values of enthalpy (ΔH°) and Gibbs free energy (ΔG°) indicate that the adsorption process are exothermic and spontaneous in nature. Fourier transform infrared (FTIR) spectroscopy and x-ray photoelectron spectroscopy (XPS) analysis of FCG before and after adsorption further reveal that the mechanism of Cu2+ ion adsorption. Further desorption and reuse experiments show that FCG still retains 96% of the original adsorption following the fifth adsorption–desorption cycle. All these results indicate that FCG is a promising recyclable adsorbent for the removal of Cu2+ ion from aqueous solution. [ABSTRACT FROM AUTHOR]- Published
- 2019
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- View/download PDF
86. The Importance of Reaction Conditions on the Chemical Structure of N,O-Acylated Chitosan Derivatives.
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Piegat, Agnieszka, Goszczyńska, Agata, Idzik, Tomasz, Niemczyk, Agata, and Fenice, Massimiliano
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CHEMICAL reactions ,CHEMICAL structure ,NUCLEAR magnetic resonance spectroscopy ,CHEMICAL derivatives ,CHITOSAN ,HYDROCHLORIC acid - Abstract
The structure of acylated chitosan derivatives strongly determines the properties of obtained products, influencing their hydrodynamic properties and thereby their solubility or self-assembly susceptibility. In the present work, the significance of slight changes in acylation conditions on the structure and properties of the products is discussed. A series of chitosan-acylated derivatives was synthesized by varying reaction conditions in a two-step process. As reaction media, two diluted acid solutions—i.e., acetic acid and hydrochloric acid)—and two coupling systems—i.e., 1-ethyl-3-(3-dimethyl-aminopropyl)-1-carbodiimide hydrochloride (EDC) and N–hydroxysulfosuccinimide (EDC/NHS)—were used. The chemical structure of the derivatives was studied in detail by means of two spectroscopic methods, namely infrared and nuclear magnetic resonance spectroscopy, in order to analyze the preference of the systems towards N- or O-acylation reactions, depending on the synthesis conditions used. The results obtained from advanced
1 H-13 C HMQC spectra emphasized the challenge of achieving a selective acylation reaction path. Additionally, the study of the molecular weight and solution behavior of the derivatives revealed that even slight changes in their chemical structure have an important influence on their final properties. Therefore, an exact knowledge of the obtained structure of derivatives is essential to achieve reaction reproducibility and to target the application. [ABSTRACT FROM AUTHOR]- Published
- 2019
- Full Text
- View/download PDF
87. Chitosan-Based Bioactive Hemostatic Agents with Antibacterial Properties—Synthesis and Characterization.
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Radwan-Pragłowska, Julia, Piątkowski, Marek, Deineka, Volodymyr, Janus, Łukasz, Korniienko, Viktoriia, Husak, Evgenia, Holubnycha, Viktoria, Liubchak, Iryna, Zhurba, Vyacheslav, Sierakowska, Aleksandra, Pogorielov, Maksym, Bogdał, Dariusz, and Fenice, Massimiliano
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BLOOD platelet activation ,ANTIBACTERIAL agents ,GLUTAMIC acid ,CELL adhesion ,BLOOD coagulation ,WATER vapor - Abstract
Massive blood loss is responsible for numerous causes of death. Hemorrhage may occur on the battlefield, at home or during surgery. Commercially available biomaterials may be insufficient to deal with excessive bleeding. Therefore novel, highly efficient hemostatic agents must be developed. The aim of the following research was to obtain a new type of biocompatible chitosan-based hemostatic agents with increased hemostatic properties. The biomaterials were obtained in a quick and efficient manner under microwave radiation using l-aspartic and l-glutamic acid as crosslinking agents with no use of acetic acid. Ready products were investigated over their chemical structure by FT-IR method which confirmed a crosslinking process through the formation of amide bonds. Their high porosity above 90% and low density (below 0.08 g/cm
3 ) were confirmed. The aerogels were also studied over their water vapor permeability and antioxidant activity. Prepared biomaterials were biodegradable in the presence of human lysozyme. All of the samples had excellent hemostatic properties in contact with human blood due to the platelet activation confirmed by blood clotting tests. The SEM microphotographs showed the adherence of blood cells to the biomaterials' surface. Moreover, they were biocompatible with human dermal fibroblasts (HDFs). The biomaterials also had superior antibacterial properties against both Staphylococcus aureus and Escherichia coli. The obtained results showed that proposed chitosan-based hemostatic agents have great potential as a hemostatic product and may be applied under sterile, as well as contaminated conditions, by both medicals and individuals. [ABSTRACT FROM AUTHOR]- Published
- 2019
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88. Treatment of Contaminated Groundwater via Arsenate Removal Using Chitosan-Coated Bentonite.
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Yee, Jurng-Jae, Arida, Carlo Vic Justo, Futalan, Cybelle Morales, de Luna, Mark Daniel Garrido, Wan, Meng-Wei, and Fenice, Massimiliano
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ARSENATES ,GROUNDWATER purification ,PERMEABLE reactive barriers ,BENTONITE ,GROUNDWATER ,THERAPEUTICS ,AMINO group - Abstract
In the present research, treatment of contaminated groundwater via adsorption of As(V) with an initial concentration of 50.99 µg/L using chitosan-coated bentonite (CCB) was investigated. The effect of adsorbent mass (0.001 to 2.0 g), temperature (298 to 328 K), and contact time (1 to 180 min) on the removal efficiency was examined. Adsorption data was evaluated using isotherm models such as Langmuir, Freundlich, and Dubinin-Radushkevich. Isotherm study showed that the Langmuir (R
2 > 0.9899; χ2 ≤ 0.91; RMSE ≤ 4.87) model best correlates with the experimental data. Kinetics studies revealed that pseudo-second order equation adequately describes the experimental data (R2 ≥ 0.9951; χ2 ≤ 0.8.33; RMSE ≤ 4.31) where equilibrium was attained after 60 min. Thermodynamics study shows that the As(V) adsorption is non-spontaneous (ΔG0 ≥ 0) and endothermic (ΔH0 = 8.31 J/mol) that would result in an increase in randomness (ΔS0 = 29.10 kJ/mol•K) within the CCB-solution interface. FT-IR analysis reveals that hydroxyl and amino groups are involved in the adsorption of As(V) from groundwater. Results of the present research serve as a tool to determine whether CCB is an environmentally safe and cost effective material that could be utilized in a permeable reactive barrier system for the remediation of As(V) from contaminated groundwater. [ABSTRACT FROM AUTHOR]- Published
- 2019
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89. Microbial Corrosion Resistance and Antibacterial Property of Electrodeposited Zn–Ni–Chitosan Coatings.
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Zhai, Xiaofan, Ren, Yadong, Wang, Nan, Guan, Fang, Agievich, Maria, Duan, Jizhou, Hou, Baorong, and Fenice, Massimiliano
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Microbial corrosion is a universal phenomenon in salt water media such as seawater and wastewater environments. As a kind of efficient protective metal coating for steel, the damage of the Zn–Ni alloy coating was found to be accelerated under microbial corrosive conditions. To solve this problem, chitosan, which is considered a natural product with high antibacterial efficiency, was added to Zn–Ni electrolytes as a functional ingredient of electrodeposited Zn–Ni–chitosan coatings. It was found that the addition of chitosan significantly and negatively shifted the electrodeposition potentials and influenced the Ni contents, the phase composition, and the surface morphologies. By exposing the coatings in a sulfate-reducing bacteria medium, the microbial corrosion resistance was investigated. The results showed that compared to the Zn–Ni alloy coating, Zn–Ni–chitosan coatings showed obvious inhibiting effects on sulfate-reducing bacteria (SRB) and the corrosion rates of these coatings were mitigated to some degree. Further research on the coatings immersed in an Escherichia coli-suspended phosphate buffer saline medium showed that the bacteria attachment on the coating surface was effectively reduced, which indicated enhanced antibacterial properties. As a result, the Zn–Ni–chitosan coatings showed remarkably enhanced anticorrosive and antibacterial properties. [ABSTRACT FROM AUTHOR]
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- 2019
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90. Cross-Linking Chitosan into Hydroxypropylmethylcellulose for the Preparation of Neem Oil Coating for Postharvest Storage of Pitaya (Stenocereus pruinosus).
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Hernández-Valencia, Carmen G., Román-Guerrero, Angélica, Aguilar-Santamaría, Ángeles, Cira, Luis, Shirai, Keiko, and Fenice, Massimiliano
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CHITOSAN ,NEEM oil ,PITAHAYAS ,AZADIRACHTIN ,ANTIOXIDANTS - Abstract
The market trend for pitaya is increasing, although the preservation of the quality of this fruit after the harvest is challenging due to microbial decay, dehydration, and oxidation. In this work, the application of antimicrobial chitosan-based coatings achieved successful postharvest preservation of pitaya (Stenocereus pruinosus) during storage at 10 ± 2 °C with a relative humidity of 80 ± 5%. The solution of cross-linked chitosan with hydroxypropylmethylcellulose with entrapped Neem oil (16 g·L
−1 ) displayed the best postharvest fruit characteristics. The reduction of physiological weight loss and fungal contamination, with an increased redness index and release of azadirachtin from the microencapsulated oil, resulted in up to a 15 day shelf life for this fruit. This postharvest procedure has the potential to increase commercial exploitation of fresh pitaya, owing to its good taste and high content of antioxidants. [ABSTRACT FROM AUTHOR]- Published
- 2019
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91. Demethoxycurcumin-Loaded Chitosan Nanoparticle Downregulates DNA Repair Pathway to Improve Cisplatin-Induced Apoptosis in Non-Small Cell Lung Cancer.
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Chen, Ying-Yi, Lin, Yu-Jung, Huang, Wei-Ting, Hung, Chin-Chuan, Lin, Hui-Yi, Tu, Yu-Chen, Liu, Dean-Mo, Lan, Shou-Jen, Sheu, Ming-Jyh, and Fenice, Massimiliano
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CHITOSAN ,CURCUMIN ,NANOMEDICINE ,DNA repair ,NON-small-cell lung carcinoma ,CISPLATIN ,DRUG side effects ,APOPTOSIS - Abstract
Demethoxycurcumin (DMC), through a self-assembled amphiphilic carbomethyl-hexanoyl chitosan (CHC) nanomatrix has been successfully developed and used as a therapeutic approach to inhibit cisplatin-induced drug resistance by suppressing excision repair cross-complementary 1 (ERCC1) in non-small cell lung carcinoma cells (NSCLC). Previously, DMC significantly inhibited on-target cisplatin resistance protein, ERCC1, via PI3K-Akt-snail pathways in NSCLC. However, low water solubility and bioavailability of DMC causes systemic elimination and prevents its clinical application. To increase its bioavailability and targeting capacity toward cancer cells, a DMC-polyvinylpyrrolidone core phase was prepared, followed by encapsulating in a CHC shell to form a DMC-loaded core-shell hydrogel nanoparticles (DMC-CHC NPs). We aimed to understand whether DMC-CHC NPs efficiently potentiate cisplatin-induced apoptosis through downregulation of ERCC1 in NSCLC. DMC-CHC NPs displayed good cellular uptake efficiency. Dissolved in water, DMC-CHC NPs showed comparable cytotoxic potency with free DMC (dissolved in DMSO). A sulforhodamine B (SRB) assay indicated that DMC-CHC NPs significantly increased cisplatin-induced cytotoxicity by highly efficient intracellular delivery of the encapsulated DMC. A combination of DMC-CHC NPs and cisplatin significantly inhibited on-target cisplatin resistance protein, ERCC1, via the PI3K-Akt pathway. Also, this combination treatment markedly increased the post-target cisplatin resistance pathway including bax, and cytochrome c expressions. Thymidine phosphorylase (TP), a main role of the pyrimidine salvage pathway, was also highly inhibited by the combination treatment. The results suggested that enhancement of the cytotoxicity to cisplatin via administration of DMC-CHC NPs was mediated by down-regulation of the expression of TP, and ERCC1, regulated via the PI3K-Akt pathway. [ABSTRACT FROM AUTHOR]
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- 2018
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92. Study of bacterial diversity of a saltern crystallisation pond ('Saline di Tarquinia', Italy) and its correlation with salinity variations
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Barghini Paolo, Pasqualetti Marcella, Gorrasi Susanna, and Fenice Massimiliano
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crystallisation pool ,marine saltern ,total bacterial community ,Saline di Tarquinia - Abstract
BARGHINI P., PASQUALETTI M., GORRASI S., ANDFENICEM.2018.Study of bacterial diversity of a saltern crystallization pond (“Saline di Tarquinia", Italy) and its correlation with salinity variations. J environ prot ecol.19(1): 139–145. PDF online: https://docs.google.com/a/jepe-journal.info/viewer?a=v&pid=sites&srcid=amVwZS1qb3VybmFsLmluZm98amVwZS1qb3VybmFsfGd4OjIyNTM3Mzg1MWQ0YmJmM2Y  
93. High lutein production by a halo-tolerant strain of Dunaliella sp. (chlorophyceae) isolated from solar salterns in central Italy
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Barghini Paolo, Giovannini Valeria, Fenice Massimiliano, Gorrasi Susanna, and Pasqualetti Marcella
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lutein ,photobioreactor, biomass production ,Dunaliella - Abstract
BARGHINI P., GIOVANNINI V.,FENICEM., GORRASI S., AND PASQUALETTI M.2018.High lutein production by a halo-tolerant strain ofDunaliellasp. (Chlorophyceae) isolated from solar salterns in Central Italy. J environ prot ecol.19(2): 704–712 PDF online:https://docs.google.com/a/jepe-journal.info/viewer?a=v&pid=sites&srcid=amVwZS1qb3VybmFsLmluZm98amVwZS1qb3VybmFsfGd4OjVkYjU0YmFmYmM5NzVkMDA
94. Fertilizing effect of microbially treated olive mill wastewater on Trifolium plants
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Vassilev, Nikolay, Vassileva, Maria, Azcon, Rosario, Fenice, Massimiliano, Federici, Federico, and Barea, Jose-Miguel
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- 1998
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95. Reuse of microbially treated olive mill wastewater as fertiliser for wheat (Triticum durum Desf.)
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Fausto Cereti, Carlo, Rossini, Francesco, Federici, Federico, Quaratino, Daniele, Vassilev, Nikolay, and Fenice, Massimiliano
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ASPERGILLUS niger , *INDUSTRIAL wastes , *BATCH processing , *DURUM wheat - Abstract
Free cells of Aspergillus niger were grown on olive mill wastewater (OMW) supplemented with rock phosphate (RP) in an air-lift bioreactor in batch and repeated-batch processes. The fungus grew well and reduced the chemical oxygen demand of the waste by 35% and 64% in the batch and repeated-batch (fourth batch) processes, respectively. Total sugar content was consistently reduced (ca. 60%) in both processes while reduction of total phenols was minimal. RP was solubilised and maximum soluble P was 0.63 and 0.75 g l−1 in the batch and repeated-batch (third batch), respectively. Several types of OMW ± RP, microbially-treated or not, were tested in a greenhouse for their fertilising ability on a soil-wheat (Triticum durum Desf.) model system. Beneficial effects were highest using OMW treated by the repeated-batch process. The treated plants showed an increase in seed biomass, spike number, and kernel weight. Harvest index was highest (0.49 ± 0.04) after treatment with OMW from the repeated-batch process. [Copyright &y& Elsevier]
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- 2004
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96. Study of microbial communities involved in the anaerobic digestion process for the energetic valorization of lignocellulosic biomass
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Mazzurco Miritana, Valentina, Fenice, Massimiliano, Massini, Giulia, and Rosa, Silvia
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Anaerobic ruminal fungi ,Biomassa lignocellulosica ,Biogas ,Microbial communities ,Digestione anaerobica ,Guild funzionali ,Lignocellulosic biomass ,Funghi anaerobi ruminali ,Illumina and FISH techniques ,Functional guilds ,Bioaugmentation ,Anaerobic digestion ,BIO/07 ,Comunità microbiche ,Tecniche Illumina e FISH - Abstract
Lo scopo del lavoro è stato quello di approfondire la comprensione delle interazioni microbiche di una complessa Comunità Microbica (CM) coinvolta nella produzione di CH4 dal processo di Digestione Anaerobica (DA). Due esperimenti sono stati condotti in batch in condizioni di mesofilia (37°C) utilizzando la paglia di grano come substrato. Nel 1° esperimento due diverse strutture di CM sono state testate per comprendere il ruolo dell’aggregazione della comunità sulle produzioni di CH4. I risultati hanno mostrato che la struttura aggregata (A) ha aumentato la produzione (42%) rispetto a quella disaggregata (D). Sia la tecnica Illumina che la FISH hanno evidenziato differenze significative nella composizione sia degli inoculi A e D che delle prove AP e DP. Nel 2° esperimento, le fasi di idrolisi e acidogenesi, sono state migliorate rispettivamente dalla bioaugmentation della CM di D con: 1) un mix di Funghi Anaerobi Ruminali (ARF) e 2) un pool di batteri fermentanti (F210). I migliori risultati sono stati ottenuti quando ARF e F210 sono stati utilizzati insieme (1397,2±73,2 ml/l CH4); solo F210 ha aumentato la produzione di CH4, ma con un’efficienza più bassa (988,3±148,2 ml/l); quando sono stati utilizzati solo gli ARF, la produzione di CH4 è stata molto bassa (250,8±14,6 ml/l) smentendo l’efficacia di una interazione diretta con i metanogeni. Inoltre l’analisi della comunità (Illumina e FISH) ha mostrato degli shift molto interessanti tra le componenti funzionali lungo le prove sperimentali. Questi risultati collocano gli ARF all’inizio della catena trofica della DA e mostrano anche come l’equilibrio tra le componenti funzionali della CM svolge un ruolo fondamentale. The aim of the work was to gain deeper insight into microbial interactions of the complex Microbial Community (MC) involved in CH4 production by Anaerobic Digestion (AD). Two batch experiments were carried out in mesophilic conditions (37°C) using wheat straw as substrate. In the 1st experiment two different structured MC were tested to investigate the role of the microbial aggregation on the CH4 productivity. The results showed that the aggregated structure (A) increased the production (42%) when compared to the disaggregated one (D). Both Illumina and FISH techniques showed significant differences in the composition both of A and D inocula, and AP and DP trials. In the 2nd experiment, the hydrolysis and acidogenesis steps were respectively enhanced by bioaugmentation of the MC of D with: 1) a mix of Anaerobic Ruminal Fungi (ARF) and 2) a fermenting bacteria pool (F210). The best results were obtained when both ARF and F210 were used (1397,2±73,2 ml/l CH4); F210 alone increased the CH4 production but with a lower efficiency (988,3±148,2 ml/l); when only ARF was used, CH4 production was very low (250,8±14,6 ml/l), disproving the effectiveness of their direct interaction with methanogens. Moreover MC analysis (Illumina and FISH) showed very interesting shifts composition along the experimental trial. These results place the ARF at the first step of the AD trophic chain and also show how the equilibrium among the microbial functional component of MC plays a pivotal role. Dottorato di ricerca in Ecologia e gestione delle risorse biologiche
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- 2017
97. Study of the bacterial biodiversity of sea water and rock samples from Antarctica
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Silvi, Silvia and Fenice, Massimiliano
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Biodiversità ,Bacteria ,Coltural techniques ,Batteri ,BIO/19 ,Tecniche fingerprinting ,Biodiversity ,Tecniche colturali ,Fingerprinting techniques - Abstract
According to the Convention on Biological Diversity, Biodiversity is “the variability among living organisms from all sources including, inter alia, terrestrial, marine and other aquatic ecosystems, and the ecological complexes of which they are part; this includes diversity within species, between species, and of ecosystems”. Antarctica is the coldest, driest, and windiest continent. The temperature can reach -30 °C, the precipitation is only 5-20 g/cm2/year and the highest recorded wind velocity is 327 km/h. It has the highest average elevation of all the continents, and about 98% of its surface, 14 million km2, is covered by ice. In these extreme conditions, only cold-adapted organisms survive, including plants, animals, and microorganisms. The Antarctic continent has been frequently cited as a pristine place, with a rather limited diversity of plants and animals, but with highly diverse microbial community. In this work we studied the bacterial community obtained from sea water and rock samples collected in Antarctica. The study has been carried out both on cultivable strains, isolated by traditional methods, and on the total bacterial community by molecular methods. The isolates were investigated in order to understand their temperature and salinity preferences. Furthermore, a detailed taxonomical study was carried out both on cultivable and total bacterial population. Study about bacterial isolates Strain isolation and preliminary tests Isolates derived from two different typology samples: sea water (BA) and rock (BAR). Sea water was sampled in various areas of Ross sea at different distances from the coast: Faraglione (300 m), Santa Maria Novella (2.5 Km), Portofino (1 Km), Thetys Bay (0 m). The rocks samples were sampled according to a longitudinal and altitudinal transect at increasing distance from the sea in 57 different places. Moreover for each sample place were considered different sites. Rocks were fragmented and strewed on PCA plates and water was filtered on membranes in order to obtain both bacteria pure cultures and DNA for the molecular investigations. Pure cultures of the isolates were obtained by plate streak method. Preliminary tests were carried out considering strain morphological characteristics (shape, color and dimensions), Gram reaction and simple biochemical tests (catalase and oxidase production). This preliminary selection permitted to remove the majority of replicates. A total of 100 isolates were obtained. Taxonomical identification of the isolates Bacterial genomic DNA was extracted from pure cultures and used for the amplification of 16S rDNA to allow taxonomical identification of each isolate. The strains were affiliates to the genera: Microbacterium, Psychrobacter, Diezia, Marisediminicola, Bacillus, Sporosarcina, Arthrobacter, Pseudomonas, Deinococcus, Brevundimonas, Frondihabitans, Rhodococcus, Agrococcus, Auraticoccus, Kocuria. Only 54% of the strains were identified to species level and the remaining were identified only to the genus level. In some cases Blast analyses supplied uncertain identification, sequences were aligned with highly similar 16S in the NCBI Genbank and phylogenetic analysis was performed. Three phylogenetic trees were created for the most important and representative groups: Pseudomonas, Arthrobacter, Psychrobacter. A phylogenetic tree was constructed for all minor groups. Growth profiles at different Temperature and salinity The optimal temperatures for growth of the various strains were tested in the range 0-45°C on PCA plates (steps of 5 °C). The majority (88%) of BA strains were able to grow in a wide temperature range. The 82% of BA were psycrotolerant, 9% were mesophilic- psychrotolerant and 9% strictly psychrophilic because they had the optima at 5°C and 10°C. All BAR strains grew in a wide temperature range. 96% of BAR were psycrotolerant and only 4% were mesophilic- psychrotolerant. The optimal salinity for growth were tested in the range 0-100 g/L on PCA plates containing different concentration of NaCl salt (steps of 5 g/L). 35% of BA strains were no halophilic, 34% were halotollerant and 31% were slightly halophilic. 65% of BAR strains were no halophilic, 26% slightly halophilic and 9% were halotollerant. Study of total bacterial community In order to have a complete overview of the bacterial community structure, by a cultivation-independent approach, total DNA was extracted from the filter-membranes and rocks samples. The bacteria biodiversity was studied by PCR-DGGE fingerprinting. The genetic target used was the hypervariable region V3 of the 16S rDNA. DGGE gel images allow the analysis of band patterns generated from the environmental samples representing the various species present in the community. A single species is identified by a single band and the relative abundance of a single species is determined by band intensity. Bacterial community in the sea water samples DGGE analysis was conducted for the bacterial communities present in marine samples from four different sites in the Ross Sea and sampled in three different times. To evaluate the structure of the bacterial community and perform a clustering analysis of the various DGGE profiles two software were used: Quantity One 1-D and Phoretix 1-D. Pearson and Dice dendrograms reflect the high heterogeneity of the sea samples and there was not a clear correlation between either in terms of sites, nor according to the time of sampling. Some bands were excised from the gel, re-amplified, sequenced and compared with NCBI GenBank database sequences. A phylogenetic tree was built to understand the relationships between the sequences. The comparison in the database shows that 67% of the identified sequences were close to unclassified species or uncultured bacteria. 155 bands were observed and the band intensity was calculate for all lanes (profiles) to have information on the relative abundance of species. The biodiversity and richness was estimated with 8 indices: Richness (n°), Weighted Richness (Rr), Stability index, Margalef index, Pielou’s evenness index, functional organization (Fo), Simpson and Shannon index. The correlation of 3 environmental variables: temperature, distance from the coast, presence/absence of ice, with the structure of the microbial communities was observed by NMDS analysis (not metric Multi Dimensional Scaling). In a two-dimensional plot the sea water samples were divided in 3 groups: α, β, γ. The temperature seems to be positively correlated to the group γ and negatively correlated to the α and β groups. While, the variables presence/absence of ice and distance from the coast were positively correlated with the α, β groups and negatively correlated to the γ groups. Bacterial community in the rock samples The endolithic bacterial community present in rocks samples collected in the McMurdo Dry Valleys of, Victoria Land, was analyzed by the PCR-DGGE technique. The work was divided in two parts: - A first analysis had allowed the study of the total bacterial communities present in 70 samples collected in 57 Victoria Lands sites. For same sites were present more rocks of different types. - A second analysis allowed to investigate how the bacterial biodiversity changes in the micro and macro rock environment. Three sites were analyzed: Richard Nunatak, Vegetation Island and Mt.Howard. For each site were tested two roks samples, both individually and combined together. In addition, from one of the two rocks were derived three sub samples, identified as A, B, C. Total rocks samples The structure of bacterial endolithic communities was studied by a cluster analysis with two software: Quantity One 1-D and Phoretix 1-D. Dice and Pearson coefficients described a strong heterogeneity among the rock samples. In addition, in the dendrograms no correlation was observed between distribution of the samples and their sampling sites. 61 bands were excised from the gel, re-amplified, sequenced and compared with NCBI GenBank database sequences. The phylogenetic analysis showed that 84% of the sequences presented no similarity with the species and/or genera known. In particular, 46% were related to sequences deposited in the data bank as “Uncultured bacterium”, 25% had similarity with sequences of know genera but a unknow species and 13% showed no similarity with deposited sequences. The biodiversity and richness indices were calculated to describe the bacterial endolithic communities. All rock samples were characterized by high values of biodiversity and richness. The results showed that biodiversity and richness were not affected by position and type of the rock. All samples showed a high heterogeneity. NMDS analysis was done to understand how five variables: altitude, distance from the sea, type of colonization, porosity and type of rock, influenced the biodiversity and richness of rock samples. In the two-dimensional plot each sample appeared to be influenced differently by the five variables and a common relationship was not observed. The results described an environment in which many variables and theit combination determined the biodiversity and richness of community. Each sample is affected differently by the variables and it was not clear how the variables influenced the endolithic bacterial distribution. Micro and macro rock habitat The micro habitats present inside the rock are influenced by numerous factors: position and orientation of rocks, altitude, permanence of the snow cover. These are significant aspects in the selection of the microorganisms and the position and portion in which the microrganism will begin colonization. This means that within the rock numerous micro habitats are present. These have different characteristics and will influence the development the type of the microbial community. Using the dendrograms based on Dice and Pearson coefficient has investigated the biodiversity into the two rocks of the same site and the diversity in the sub samples, identified as A, B, C. The bacterial endolithic communities had a great heterogeneity even if the bacterial profiles in the same sites were similar and had common bands. The results obtained by biodiversity and richness indices for Richard Nunatak, Mt.Howard and Vegetation Island samples confirmed the results obtained other analysis. These results reinforce the hypothesis that Antarctic rock environment contains numerous micro habitats and the rock represents a complex ecosystem in which each factor causes large variations in microbial communities. Taxonomic DGGE results obtained by the total community study were quite different from those gained by the pure cultures. This could be explained by the limits of two approaches. The first is a cultural technique that allows to study only bacteria that can grow in laboratory. The second is an cultured indipendent technique, but the DGGE can detect bacteria representing at least 1% of the total community. It is possible that some species, present in a very low percentage and not observed in DGGE, had prevailed under to favorable culture conditions during the isolation procedures. This work is very interesting to understand the structure of bacterial communities in sea water and rocks samples. In particular, Biodiversity and Richness in rock habitats is extremely high and the results underlined that it’is necessary to increase the knowledge so far collected and further expand the studies on bacterial communities endolithic Antarctica. Il significato di Biodiversità, con le sue diverse accezioni, lo si può comprendere più facilmente quando non lo si considera come termine assoluto, ma come qualcosa dipendente dal contesto che si sta studiando. De Long nel 1996 afferma: “La Biodiversità è un attributo di un territorio e in particolare si riferisce alla varietà all'interno e tra organismi viventi, nell’insieme di organismi viventi, nelle comunità biotiche e nei processi biotici presenti in natura o modificati dall'uomo. La Biodiversità può essere misurata in termini di diversità genetica e con l'identità e il numero di diversi tipi di specie, insieme di specie, comunità biotiche e processi biotici, e la quantità (abbondanza, biomassa, copertura,) e la struttura. Può essere osservata e misurata in qualunque scala spaziale che va da micrositi a differenti habitat per l'intera biosfera”. L’Antartide per posizione geografica, caratteristiche fisiche e la quasi totale assenza di perturbazioni antropiche rappresenta un ambiente estremo particolarmente interessante per la ricerca scientifica; non solo per lo studio della Biodiversità che qui si può osservare, ma anche per la ricerca dei vari processi evolutivi e i cambiamenti climatici che prendono parte al “global change”. L'Antartide è il continente più meridionale della terra, si sviluppa quasi totalmente all'interno del Circolo Polare Antartico e comprende i mari e le terre che circondano il Polo Sud. E’ il continente più freddo, più secco e ventoso. La temperatura varia da valori che si aggirano attorno a 0°C in estate sulla costa, fino a sfiorare i -90°C in inverno a 3000 metri di quota. Le precipitazioni sono piuttosto scarse e si aggirano intorno ai 5-20 g/cm2/anno. I venti possono superare i 200 km/h. Ha la più alta elevazione media se confrontato con gli altri continenti e il 98% del suo territorio è coperto dalla Calotta glaciale Antartica con uno spessore medio di 1,6 km. Il progetto di ricerca presentato prevede lo studio delle popolazioni batteriche presenti in campioni di acqua marina e di rocce prelevate in diverse zone dell’Antartide. L’attività è stata caratterizzata da un lavoro sperimentale suddiviso in due parti fondamentali: la prima, legata ad un approccio basato su tecniche coltura-indipendenti e la seconda legata all’utilizzo di tecniche colturali. I campioni marini provenienti dal mare di Ross e i campioni di roccia sono stati raccolti durante la campagna 2010-2011 del progetto PNRA (Programma Nazionale di Ricerche in Antartide). Le acque sono state prelevate in tre periodi distinti, in 4 differenti siti a differente distanza dalla costa: Faraglione, Santa Maria Novella, Portofino e Thetys Bay, mentre le rocce sono state campionate secondo un transetto longitudinale e altitudinale a crescente distanza dal mare nelle Valli Secche di McMurdo, Terra Vittoria. Le informazioni sulle comunità batteriche delle rocce antartiche non sono numerose e poco si conosce dei generi e delle specie che è possibile osservare in questi particolari habitat. Con questo lavoro è stato possibile ampliare e approfondire le conoscenze sulla struttura delle comunità batteriche endolitiche antartiche ed inoltre, lo studio delle comunità batteriche delle acque del mare di Ross hanno permesso di confrontare le due diverse tipologie di comunità evidenziando come alcuni generi siano presenti in entrambi gli ambienti, mentre altri siano specifici dell’uno o dell’altro habitat. Studio dei ceppi isolati Isolamento e test preliminari I ceppi isolati derivano da campioni di acqua di mare (BA) e campioni di roccia (BAR). Le rocce erano frammentate e poste su piastre di PCA. L’acqua è stata preventivamente filtrata e le membrane poste su piastre di PCA. Le colture pure erano ottenute mediante la tecnica dello striscio. Uno screening iniziale e test preliminari, studio morfologico della cellula e della colonia e test biochimici, hanno permesso di eliminare replicati consentendo di ottenere 100 isolati. Identificazione tassonomica dei ceppi mediante il gene 16S rDNA Il DNA era estratto dalle colture pure è stato usato per amplificare il gene 16S rDNA, il quale ha permesso l’identificazione tassonomica di ogni isolato. Solo il 54% dei ceppi potevano essere identificati a livello di specie, mentre i restanti erano identificati solo al livello di genere. I ceppi erano affiliati ai generi: Microbacterium, Psychrobacter, Diezia, Marisediminicola, Bacillus, Sporosarcina, Arthrobacter, Pseudomonas, Deinococcus, Brevundimonas, Frondihabitans, Rhodococcus, Agrococcus, Auraticoccus, Kocuria. Sono stati costruiti quattro alberi filogenetici allineando le sequenze dei ceppi identificati con le sequenze presenti in banca dati NCBI GenBank con le quali si erano ottenuti i più alti valori di similarità. Gli alberi filogenetici erano costruiti per i tre generi più rappresentativi: Pseudomonas, Arthrobacter, Psychrobacter, mentre un albero era costruito per tutti i gruppi minoritari. Profili di crescita a differenti temperature e concentrazioni saline Il profilo di crescita a differenti temperature per i ceppi antartici era determinato monitorando la crescita delle colonie batteriche su piastre di PCA in un intervallo di temperatura tra 0 e 45°C con step di 5°C. 88% dei ceppi BA erano in grado di crescere in un ampio intervallo di temperatura e solo il 12% arrestava la propria crescita sotto i 35°C. L’82% dei ceppi BA erano psicrotolleranti, il 9% erano mesofili-psicrotolleranti e il 9% erano psicrofili stretti, avendo un optimum a 5-10°C. Tutti i BAR crescevano in un ampio intervallo di temperatura; il 96% erano psicrotolleranti e solo il 4% erano mesofili-psicrotolleranti. L’optimum e il range di crescita a differenti concentrazioni saline era testato monitorando la crescita delle colonie batteriche su piastre di PCA contenenti NaCl in concetrazioni 0-100 g/L, con intervalli di 5g/L. Il 35% dei BA erano non alofili, il 34% erano alotolleranti e il 31% erano moderatamente alofili. I ceppi BAR erano principalmente (65%) non alofili, il 26% erano moderatamente alofili e il 9% erano alotolleranti. Studio della comunità batterica totale Oggi la comunità scientifica ritiene che circa il 99% dei microrganismi presenti in natura, non può essere isolato in colture pure. Quindi, per comprendere meglio la diversità microbica e il ruolo che essa ha nel mantenimento dell'ecosistema, sono necessarie ulteriori tecniche che completano e complementano l'approccio delle tecniche colturali. Le Tecniche di Fingerprinting molecolare consentono un confronto diretto del DNA di comunità microbiche provenienti da diversi campioni e sono considerate strumenti importanti per valutare rapidamente i cambiamenti della struttura delle comunità nel tempo e nello spazio. La biodiversità batterica era studiata mediante la tecnica di fingerprinting PCR-DGGE. Il target genico scelto era la regione ipervariabile V3 del gene 16S rDNA. La DGGE si basata sull’elettroforesi di frammenti di DNA su un gel di poliacrilammide contenente un gradiente crescente di sostanze denaturanti, urea e formammide. Studio della comunità batterica nei campioni di acqua marina Mediante la tecnica DGGE è stata condotta un’analisi delle comunità batteriche presenti in campioni marini provenienti da quattro differenti siti del mare di Ross e campionati in tre differenti tempi.Per valutare la struttura della comunità batterica e condurre un’analisi di clusterizzazione dei profili dei differenti campioni sono stati usati due software di analisi d’immagine: Quantity One 1-D e Phoretix 1-D. Sia il dendrogramma basato sul coefficiente di Dice che quello basato sul coefficiente di Pearson rispecchiano l’elevata eterogeneità che caratterizza i campioni studiati evidenziando come non ci sia una netta correlazione fra di loro, né a livello di siti, né in base ai periodi di campionamento. Per ottenere una visione più dettagliata delle specie presenti nei campioni del mare di Ross, le bande più rappresentative sono state excise dal gel di DGGE, ri-amplificate, sequenziate e confrontate con le sequenze depositate in banca dati NCBI GenBank. Inoltre è stato realizzato un albero filogenetico che descrive le relazioni fra le sequenze ottenute. Il confronto in banca dati mostra come il 67% delle sequenze identificate siano appartenenti a specie non ancora classificate o non coltivabili. Questi risultati evidenziano come le conoscenze sulla biodiversità microbica in ambienti poco conosciuti ed estremi, come l’Antartide, siano ancora molto limitate. L’analisi d’immagine elaborata con il software Quantity One 1-D ha permesso di individuare un totale di 155 bande e calcolare per tutte i profili l’intensità di ogni banda così da avere informazioni sull’abbondanza relativa delle specie. La biodiversità e la ricchezza nei diversi campioni è stata stimata attraverso l’utilizzo di otto diversi indici: Ricchezza (n°), Ricchezza ponderata (Rr), indice di Stabilità, indice di Margalef , indice di Pielou, Organizzazione funzionale (Fo), indice di Simpson e Shannon. Inoltre, per comprendere l’effetto di tre variabili ambientali: temperatura dell’acqua durante il campionamento, presenza o assenza di ghiaccio e distanza dalla costa, sulla struttura delle comunità microbiche si è scelto di applicare agli indici calcolati sui profili di DGGE la tecnica di orientamento NMDS (Non metric Multi Dimensional Scaling), la quale ha permesso di evidenziare se e come le componenti abiotiche fossero correlate positivamente o negativamente con la ricchezza e biodiversità dei campioni. Nel grafico bi-dimensionale i campioni erano suddivisi in tre gruppi: α, β, γ. Il gruppo γ sembrava essere positivamente correlato alla temperatura diversamente dai gruppi α e β che sembravano correlati negativamente. Le variabili presenza/assenza di ghiaccio e distanza dalla costa erano correlate positivamente con α, β e negativamente con γ. Studio della comunità batterica nei campioni rocciosi La comunità batterica endolitica presente nelle rocce raccolte nelle Valli Secche di McMurdo, Terra Vittoria, è stata analizzata mediante la tecnica di fingerprinting molecolare PCR-DGGE. La biodiversità batterica totale è stata studiata a due differenti livelli: una prima analisi ha permesso lo studio della comunità batterica totale presente nei campioni raccolti nelle 57 località analizzando anche rocce di differente tipologia proveniente da uno stesso sito. Una seconda analisi ha permesso di investigare se e come la biodiversità batterica cambi all’interno del micro e macro habitat roccioso. Per studiare la comunità batterica due campioni di rocce della stessa tipologia e provenienti da uno stesso sito sono stati processati mediante DGGE, sia separatamente che uniti insieme. Inoltre, da una delle due rocce sono stati ricavati tre sotto campioni, identificati come A, B, C, processati separatamente per comprendere come la biodiversità cambi all’interno del micro habitat roccioso. Analisi dei campioni rocciosi Per valutare la struttura delle comunità batteriche endolitiche e realizzare un’analisi di clusterizzazione dei profili dei differenti campioni sono stati usati due software di analisi d’immagine: Quantity One 1-D e Phoretix 1-D. L’analisi di cluster si è basata sul coefficiente di correlazione di Dice e sul coefficiente di Pearson. Entrambi i coefficienti hanno evidenziato la forte eterogeneità che si ha tra i campioni rocciosi. Inoltre, non è stato possibile individuare una correlazione tra la distribuzione dei profili all’interno del dendrogramma e la tipologia di roccia e la posizione dei siti da cui i campioni provengono. L’analisi mediante DGGE dei 70 campioni rocciosi ha evidenziato profili con numerose bande e di queste 61 sono state excise dal gel, ri-amplificate e i prodotti di PCR sono stati sequenziati. Le sequenze sono state confrontate con quelle depositate in banca dati NCBI GenBank e utilizzate per l’analisi filogenetica. I risultati ottenuti hanno mostrato come l’84% delle sequenze non presentavo similitudine con specie e/o generi noti. In particolare, il 46% erano simili a sequenze depositate in banca dati come “Uncultured bacterium”, il 25% presentano maggiore similarità con sequenze di specie non coltivabili appartenenti a generi conosciuti e il 13% non mostravano alcuna similarità con sequenze depositate e questo non permetteva l’attribuzione ad alcuna specie nota. Solo il 16% delle sequenze era riconducibile a generi e/o specie note. Mediante gli indici di biodiversità e ricchezza è stato possibile descrivere ulteriormente la struttura delle comunità batteriche endolitiche dei differenti siti. Tutte le rocce erano caratterizzate da un’elevata eterogeneità; inoltre, i risultati mostravano come la diversità e la ricchezza in specie non fosse correlata con la posizione e il sito di campionamento. Al fine di comprendere come la ricchezza e la biodiversità calcolate per le comunità batteriche che colonizzano le 70 rocce studiate possano essere correlati ad alcuni fattori, è stata utilizzata l’analisi di orientamento NMDS (Non-Metric Multidimensional Scaling). Nell’analisi multivariata le variabili prese in considerazione erano: distanza dal mare (km), altitudine (m), il tipo di colonizzazione, di porosità e il tipo di roccia. Analisi del micro e macro habitat roccioso I micro habitat che si sviluppano all’interno della roccia sono influenzati da numerosi fattori come la posizione, l’esposizione, l’orientamento, l’altitudine, la permanenza della copertura nevosa. Questi sono aspetti significativi nella scelta da parte dei microrganismi della posizione e della porzione nella quale avverrà la colonizzazione. Mediante i dendrogrammi basati sul coefficiente di Dice e Pearson si è studiata la biodiversità e le relazioni esistenti di rocce campionate all’interno di uno stesso sito. Inoltre si è cercato di comprendere se e come all’interno di una stessa roccia esistano più microhabitat con una differente distribuzione della comunità batterica. I risultati ottenuti mostrano come la struttura delle comunità batteriche sia caratteristica per ogni sito e come all’interno di ognuno e dei sottogruppi A, B, C non ci siano differenze rilevanti che fanno sì che i loro profili possano clusterizzare in posizioni differenti dal gruppo a cui appartengono. Mediante il software Quantity-one è stato possibile elaborare per ogni sito il confrontato tra i profili permettendo di indicare le bande comuni a tutti e quelle presenti solo in alcuni. I risultati ottenuti sembrerebbero descrivere la roccia antartica come un ambiente caratterizzato da numerosi micro habitat all’interno dei quali si sviluppano numerose comunità batteriche particolari. Quindi le estreme condizioni che caratterizzano il continente Antartide fanno si che anche piccole differenze nell’esposizione e nell’inclinazione della roccia definiscano se e come la roccia venga colonizzata. Gli indici di biodiversità e ricchezza calcolati per i siti Richard Nunatak, Mt.Howard e Vegetation Island evidenziano dei campioni caratterizzati da un elevata diversità confermando i risultati ottenuti dall’analisi del confronto dei profili di uno stesso sito. Grazie a questo lavoro di tesi è stato possibile ampliare le informazioni sulle comunità batteriche endolitiche antartiche. Le informazioni su queste comunità non sono particolarmente abbondanti, quindi la possibilità di introdurre nuove informazioni è estremamente importante per capire sia come la vita si sviluppi in ambienti estremi come l’Antaertide sia quale siano i limiti a cui gli organismi viventi sono in grado di spingersi. Dottorato di ricerca in Ecologia e gestione delle risorse biologiche
- Published
- 2015
98. Study of bacterial diversity of the 'Saline di Tarquinia': culture dependent and independent methods
- Author
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Aquilanti, Arianna and Fenice, Massimiliano
- Subjects
PCR-DGGE ,Bacterial diversity ,Culture dependent and independent methods ,Solar salterns ,Saline ,BIO/19 ,hyperaline environments ,Metodi colturali e non colturali ,Ambienti iperalini ,Diversità batterica - Abstract
Obiettivo di questo lavoro di tesi è stato lo studio delle comunità batteriche presenti nelle acque delle Saline di Tarquinia, Viterbo (Italia) attraverso metodi colturali e coltura indipendenti ed il monitoraggio del cambiamento nella composizione di tali comunità in seguito a variazioni nutrizionali, climatiche, stagionali,… Nelle Saline di Tarquinia sono stati eseguiti vari studi relativi agli organismi eucarioti che popolano tale ambiente, ma non sono mai state studiate finora le comunità batteriche presenti. Allo scopo di ottenere informazioni sia a livello ecologico, sia per possibili future applicazioni in ambito biotecnologico, lo studio è stato eseguito sia su batteri coltivabili, isolati con i metodi tradizionali, sia sulle comunità batteriche totali, utilizzando metodi molecolari (PCR-DGGE). Gli ecosistemi iperalini sono considerati ambienti estremi e le saline ne sono un esempio. Esse sono caratterizzate da una serie di vasche interconnesse nelle quali la concentrazione salina aumenta progressivamente fin oltre la saturazione e sono caratterizzate da una elevata variabilità dei parametri chimico-fisici, i quali sono soggetti a forti fluttuazioni. Le Saline di Tarquinia sono state utilizzate per la produzione industriale di sale fino al 1997 e dal 1980 sono state istituite Riserva Naturale. Sono caratterizzate da oltre 100 vasche. Allo scopo di poter eseguire una comparazione con una salina ancora attiva nella produzione di sale, è stato condotto uno studio preliminare presso “Salina Chiusicella” all’interno delle saline di Trapani e Paceco. Presso le saline di Tarquinia è stata eseguita una campagna di campionamento triennale, che ha previsto il prelievo mensile di campioni di acqua per i primi due anni, a partire dal mese di maggio 2012 e settimanale per tre mesi significativi a livello stagionale (maggio 2014, settembre 2014 e febbraio 2015) durante il terzo anno. La campagna di campionamento ha previsto il prelievo di campioni di acqua da 14 vasche scelte secondo un gradiente di salinità e dal mare limitrofo per un totale di 15 campioni. Ciascun campione rappresenta la media di tre sottocampioni prelevati da tre punti significativi in ciascun sito. Presso Salina Chiusicella sono stati invece eseguiti due campionamenti (settembre 2013 e settembre 2014) da 10 vasche scelte secondo un gradiente di salinità. Isolamento dei batteri coltivabili e test preliminari I campioni di acqua sono stati filtrati su membrane di nitrocellulosa allo scopo di ottenere colture batteriche pure incubando il filtro su piastre di PCA (Plate Count Agar) a differenti concentrazioni saline scelte in un range compreso tra 0 e 250‰ con step di 50‰. Si è proceduto quindi ad una caratterizzazione morfologica e biochimica ed alla colorazione di Gram, che hanno permesso di ottenere 39 diversi isolati. Identificazione degli isolati Il DNA genomico batterico è stato estratto dalle colture pure ad utilizzato per l’amplificazione del 16S rDNA per permettere l’identificazione degli isolati. 29 ceppi su 39 sono stati identificati a livello di specie (77% ca.). 26 di questi hanno mostrato, dal confronto in banca dati GenBank, valori elevati di identità (99-100%). Tutti gli altri isolati sono stati identificati a livello di genere. 29 ceppi appartenevano alla classe γ-Proteobacteria e 14 di questi all’ordine Oceanospirillales. Tra questi, i generi Halomonas e Salinivibrio erano la maggioranza (11 e 7 isolati rispettivamente). In particolare, all’interno del genere Halomonas sono state identificate 7 differenti specie. Sono stati isolati inoltre ceppi appartenenti agli ordini Enterobacteriales (generi Yersinia e Erwinia), Pseudomonadales (generi Pseudomonas e Psychrobacter), Alteromonadales (genere Idiomarina), Vibrionales (genere Salinivibrio), Rhodobacterales (genere Ruegeria), Actinomycetales (generi Rhodococcus, Nesterenkonia, Arthrobacter e Microbacterium) Bacillales (generi Bacillus, Marinococcus e Planococcus) e Aeromonadales (genere Aeromonas). Le sequenze 16S rDNA dei ceppi isolati sono state allineate tra loro e con quelle che dal confronto in banca dati GenBank hanno mostrato la maggior percentuale di similarità con esse, allo scopo di eseguire analisi filogenetiche. Sono stati ottenuti tre alberi filogenetici utilizzando il metodo della massima verosimiglianza: uno comprendente tutti i ceppi isolati, il secondo relativo all’ordine Oceanospirillales e il terzo relativo agli altri ordini. Sulla base dei risultati ottenuti, alcuni dei ceppi sono stati identificati con certezza a livello di specie mentre altri, a causa della lunghezza dei rami o della posizione esterna nei raggruppamenti, probabilmente appartengono a specie nuove. Per tutti gli altri ceppi, l’identificazione è stata possibile solo a livello di genere. In molti casi questo potrebbe essere dovuto allo scarso potere informativo del gene target utilizzato per discernere la relazioni al di sotto del livello di genere. Determinazione dei profili di crescita a differenti temperature La crescita dei ceppi batterici è stata testata nel range 0-45°C, con step di 5°C, su piastre di PCA con concentrazione salina pari all’optimum per ogni ceppo. La maggior parte di essi (54% ca.) mostrava l’optimum a 30°C. L’optimum più basso è stato registrato per due ceppi (S8 e S34) ed era pari a 20°C. Nessun ceppo mostrava un optimum superiore ai 35°C. La maggior parte degli isolati (64% ca.) mostrava l’optimum nel range mesofilo, ma era in grado di crescere anche a 0-5°C. Questi organismi potrebbero essere definiti come mesofili-psicrotolleranti. Solo il 3% ca. dei ceppi mostrava un optimum a 20°C e cresceva nel range 5-35°C. Questi ceppi possono essere definiti psicrotrofi. Il resto degli isolati (ca. 33%) cresceva a partire da temperature pari o superiori ai 10°C e mostrava un optimum intorno ai 30-35°C. Per questa ragione possono essere definiti mesofili. Quasi tutti i ceppi studiati potrebbero essere considerati euritermi, indicando l’adattamento ad ampie variazioni di temperatura tipiche di un ambiente come quello delle saline. Se comparati con le stesse specie descritte in letteratura, i ceppi testati mostravano un range di crescita spostato verso temperature più basse, ma gli optimum non erano molto differenti. Determinazione dei profili di crescita a differenti concentrazioni di cloruro di sodio La crescita dei ceppi è stata testata nel range 0-320‰, con step di 40‰ su piastre di PCA. Il 46% ca. dei ceppi mostrava un optimum di crescita pari a 40‰ di NaCl e ca. il 23% mostrava l’optimum ad 80‰. La maggior parte di questi ceppi (ca. 81%) non era in grado di crescere in assenza di NaCl ed il 22% cresceva in presenza di concentrazioni saline uguali o superiori a 240‰. Tra i ceppi che mostravano l’optimum a 40‰ di NaCl, alcuni (BS34, S1, S39, S46 e S48) erano in grado di crescere bene anche in assenza di sale. Potrebbero quindi essere definiti come alofili moderati normotolleranti. Circa il 31% dei ceppi mostrava un optimum pari a 0‰, ma era in grado di tollerare concentrazioni saline relativamente alte. Questi microrganismi possono essere definiti quindi alotolleranti. La maggior parte dei ceppi potrebbe essere considerata eurialina, poiché in grado di crescere in un range piuttosto ampio di salinità. Questo fa sì che l’organismo sia in grado di adattarsi all’elevata variabilità tipica di un ambiente come quello delle saline, in cui la salinità è soggetta a forti fluttuazioni. Se comparati con le stesse specie descritte in letteratura, i ceppi testati manifestano un range di crescita meno ampio. Per quanto riguarda gli optima sembrerebbe esserci invece una buona corrispondenza con i pochi dati disponibili in bibliografia. Citometria di flusso Informazioni più dettagliate concernenti l’omeostasi e lo stato fisiologico delle cellule batteriche sottoposte a differenti concentrazioni saline, sono state ottenute da studi di citometria di flusso nel range 0-280‰ con step di 40‰, per quattro ceppi di interesse (BS6, S17, S19 e S28). Per i ceppi BS6 e S28, i risultati ottenuti dalla citometria di flusso confermano quelli ottenuti con la prova di crescita su piastra. Per i ceppi S17 e S19, i risultati ottenuti dalla prova di crescita su piastra, durante la quale era stata evidenziata crescita fino a 280‰ seppur limitata a partire dai 200‰, non sono stati confermati. Per il ceppo S19 infatti, la crescita era manifestata fino a 200‰, ma con il graduale aumento della salinità era possibile notare un aumento proporzionale della sofferenza cellulare. Per il ceppo S17 invece, la crescita si arrestava repentinamente a 120‰, mostrando segni di sofferenza già dalle prime ore di incubazione. È importante sottolineare che la richiesta e la tolleranza di sale per molte specie, varia al variare delle condizioni di crescita, come ad esempio la temperatura o la composizione del terreno. Inoltre la prova di citometria di flusso è stata condotta in terreno liquido, quindi ci possono essere differenze che influiscono sulla crescita del microrganismo. Una delle più rilevanti è la diversa disponibilità di ossigeno a cui il batterio è sottoposto rispetto ad una crescita su terreno solido in piastra. Studio delle comunità batteriche La diversità batterica è stata studiata inoltre utilizzando la tecnica di fingerprinting PCR-DGGE ed i patterns di bande ottenuti sono stati comparati tra loro e sottoposti ad analisi di clusterizzazione attraverso l’utilizzo dei programmi Quantity-One e Phoretix 1D. Una singola specie è rappresentata da una singola banda e la sua abbondanza relativa è determinata dall’intensità della banda. L’analisi di clusterizzazione è stata eseguita utilizzando il metodo UPGMA ed i coefficienti di Dice e Pearson. Dall’ analisi dei gel eseguiti è stata riscontrata una notevole variabilità nei profili di fingerprinting, che non sono risultati omogenei né nel numero di bande rilevate né nella loro distribuzione all’interno del gel. Inoltre, nel corso dei diversi mesi di campionamento, i raggruppamenti all’interno dei dendrogrammi non risultavano correlati alla salinità delle vasche campionate. Questo risultato è stato confermato anche per i mesi estivi, in cui sono state rilevate le differenze più marcate tra i valori di salinità delle varie vasche. Infine, dalle analisi di clusterizzazione è emerso che le vasche in cui si sono registrati sempre i valori di salinità più elevati, non presentavano nella maggior parte dei casi un numero di bande inferiore rispetto agli altri siti nel corso dei campionamenti effettuati. Allo scopo di rappresentare graficamente l’uniformità delle comunità batteriche studiate, sono state calcolate le curve di Pareto-Lorenz basate sull’intensità delle bande presenti nei profili. Ogni profilo di DGGE è descritto da una curva che viene disegnata in un grafico in cui in ascissa è riportato il numero cumulativo normalizzato di bande e in ordinata le rispettive intensità cumulative normalizzate. Per interpretare numericamente la curva si fa riferimento alla proiezione del valore dell’asse y nel punto in cui le intensità corrispondono alla verticale del 20% sull’asse x (indice di organizzazione funzionale - Fo). Le curve di Pareto-Lorenz sono state eseguite per tutti i siti di campionamento e per i mesi di agosto 2012, marzo 2013 e maggio 2012, caratterizzati rispettivamente da salinità massima, minima e intermedia rispetto all’intero periodo di campionamento. I valori medi di Fo calcolati per i mesi di agosto e maggio 2012 (35% e 32% rispettivamente), descrivevano comunità con una medio-bassa organizzazione funzionale e con elevata uniformità, in grado quindi di reagire al mutare delle condizioni ambientali, preservando la loro funzionalità. Questi risultati sembrerebbero adattarsi all’ambiente delle saline, caratterizzato da elevata instabilità dei parametri ambientali, a cui solo una comunità con queste caratteristiche sarebbe in grado di far fronte. Per quanto riguarda il mese di marzo 2013 invece, il valore medio di Fo sale al 43%. Si tratta del mese in cui sono stati registrati i valori di salinità più bassi rispetto ai due anni di campionamento. In questo caso quindi, grazie ad un aumento delle potenzialità fisico-chimiche dei siti campionati, si è rilevato anche un aumento dell’organizzazione funzionale della comunità. Le curve di Pareto-Lorenz sono state calcolate anche per i primi due anni di campionamento per il sito vascone. L’organizzazione funzionale è risultata essere molto differente tra i vari mesi, evidenziando quindi una elevata variabilità nella struttura della comunità batterica nel tempo. Infine è stata eseguita la Moving Windows Analysis per valutare i cambiamenti nella struttura della comunità batterica presente in ciascun sito campionato, a partire dalla matrice di similarità delle curve densiometriche dei profili DGGE. Per tutte le vasche è stata rilevata una elevata dinamicità nel tempo nella composizione delle comunità batteriche presenti. NMDS (No metric multidimensional scaling) Il metodo NMDS è stato eseguito per ogni sito campionato e per tutti i mesi di campionamento, per la ricerca dei rapporti tra il set di dati biologici (conte totali e vitali, matrice delle bande DGGE e Richness) e i dati ambientali rilevati (salinità, temperatura, ossigeno disciolto, pH, clorofeopigmenti e BOD5). I diagrammi di ordinamento sono stati generati utilizzando il coefficiente di similarità Bray-Curtis. Osservando i diagrammi ottenuti è stato possibile notare che essi descrivono uno schema di ordinamento caratteristico per ciascuna delle vasche campionate e questo risultato è stato confermato anche dall’NMDS eseguita per la ricerca dei rapporti tra gli indici di biodiversità calcolati (Richness, indici di Simpson e Shannon-Wiener ed Evenness) e i dati ambientali utilizzati anche per la precedente analisi. Studio delle variazioni mensili Al termine dei due anni di campionamento a cadenza mensile, sono stati eseguiti campionamenti a cadenza settimanale per tre mesi significativi a livello stagionale (maggio 2014, settembre 2014 e febbraio 2015). In questo modo è stato possibile ottenere un confronto su un ulteriore anno di campionamento, almeno per alcuni mesi, ed è stato possibile rilevare anche le variazioni mensili per questo ambiente. I dati relativi al mese di febbraio 2015 sono ancora in fase di elaborazione. I risultati confermano quelli ottenuti con la campagna di campionamento a cadenza mensile: è stata riscontrata una elevata variabilità nella composizione delle comunità batteriche tra i vari siti e i raggruppamenti all’interno dei dendrogrammi, anche in questo caso, non risultano correlati alla salinità delle vasche campionate. Al fine di comprendere le relazioni esistenti tra le comunità batteriche di uno stesso mese nel corso dei vari campionamenti, è stata eseguita un’analisi combinata dei gel sia per il mese di maggio sia per quello di settembre. Per questi è stato possibile eseguire un raffronto per tutti e tre gli anni di campionamento. L’analisi combinata è stata eseguita utilizzando il software Phoretix 1D. I dendrogrammi relativi alla similarità dei patterns di bande sono stati calcolati utilizzando il coefficiente di Dice e l’algoritmo UPGMA. Dai dendrogrammi è stato possibile osservare che, salvo alcune eccezioni, le vasche clusterizzano tra di loro in funzione della data di campionamento. Quindi i profili per le varie vasche, prelevate allo stesso tempo, risultano più simili tra loro di quanto non lo siano i profili ottenuti per la stessa vasca nel corso dei tre anni. Studio preliminare sulle Saline di Trapani e Paceco Al fine di poter eseguire un confronto della diversità batterica tra saline attive nella produzione di sale e non, si è proceduto ad uno studio preliminare presso “Salina Chiusicella” all’interno delle Saline di Trapani e Paceco. Le analisi di clusterizzazione rilevano una differenza sostanziale con i risultati ottenuti per le saline di Tarquinia. È stato possibile infatti rilevare, in questo caso, una suddivisione netta in diversi raggruppamenti, in relazione ai valori di salinità delle vasche campionate. Inoltre, durante il mese di settembre 2014, sebbene nella maggior parte dei casi siano stati rilevati valori di salinità più elevati, è stata evidenziata una maggior diversità batterica. In entrambe le saline quindi non è stato possibile trarre una qualsiasi conclusione netta relativa all’andamento del numero di OTU al variare della salinità in questi ambienti. Questo conferma la complessità nella variazione della struttura delle comunità batteriche lungo un gradiente di salinità e suggerisce di rivalutare il ruolo del dominio batteri negli ambienti “estremi”. In this work we have studied the bacterial communities present in the water environments of “Saline di Tarquinia” Viterbo (Italy) through culture dependent and independent methods and the changes in the communities composition as a function of seasonal, climatic and nutritional variations recorded. Various studies were performed in the “Saline in Tarquinia” on the eukaryotic organisms that inhabit that environment, but the bacterial communities present have never been studied so far. In order to obtain information both at the ecological level and for possible future applications in biotechnology, the study has been carried out both on cultivable strains, isolated by traditional methods, and on the total bacterial communities by molecular methods (PCR-DGGE). Hyperaline ecosystems are considered as extreme environments and the solar salterns are typical examples. They are characterized by a series of interconnected ponds in which salt concentration increases progressively up to saturation. They also show a high variability of physical-chemical parameters such as temperature and salinity and dissolved oxygen, which are subject to strong fluctuations. “Saline di Tarquinia” were used for industrial salt production until 1997 and since 1980 they had been transformed into a natural reserve. They have more than 100 ponds. In order to do a comparison with a solar saltern still active in the salt production, we have carried out a preliminary study in the “Salina Chiusicella” of “Saline di Trapani e Paceco” solar saltern. In “Saline di Tarquinia” the sampling campaign was planned for three years starting from May 2012. From May 2012 to April 2014 we carried out monthly sampling and in the third year we performed weekly sampling for three months: May 2014, September 2014 and February 2015. Sampling campaign consisted in the collection of water from 14 ponds with a salinity gradient. The nearby sea water was also collected as a reference. These samples represented the average of three sub-samples taken from three separate points in each site. In “saline di Trapani e Paceco” we carried out two samplings in September 2013 and September 2014 from 10 ponds with a salinity gradient. Strain isolation and preliminary tests Water samples were filtered through membranes in order to obtain both bacteria pure cultures and DNA for molecular studies. Pure cultures of isolates were obtained by plate streak method on PCA (Plate Count Agar) with different salt concentration from 0 to 250‰ with steps of 50‰. Preliminary tests were carried out considering strain morphological characteristics (shape, color and dimensions), Gram reaction and simple biochemical tests (catalase and oxidase production). This preliminary selection permitted to remove the majority of replicates and to keep 39 isolates. Taxonomical identification of isolates Bacterial genomic DNA was extracted from pure cultures and used for amplification of 16S rDNA, to allow taxonomical identification of each isolate. 29 strains out of 39 (ca. 77%), were identified at species level. 26 strains of these showing high identity (99-100%). All other isolates were identified at the genus level. 29 strains out of 39, belonged to the γ-Proteobacteria class and 14 of these belonged to the Oceanospirillales order. Among these strains, the genera Halomonas and Salinivibrio were the mayority (11 and 7 isolates respectively). In particular, 7 different species have been identified in the Halomonas genus. We have also isolated strains of Enterobacteriales (genera Yersinia and Erwinia), Pseudomonadales (genera Pseudomonas and Psychrobacter), Alteromonadales (genus Idiomarina), Vibrionales (genus Salinivibrio), Rhodobacterales (genus Ruegeria), Actinomycetales (genera Rhodococcus, Nesterenkonia, Arthrobacter and Microbacterium) Bacillales (genera Bacillus, Marinococcus and Planococcus) and Aeromonadales (genus Aeromonas) orders. In addition, the 16S rDNA sequences of the studied strains were aligned between them and with highly similar 16S in the GenBank and phylogenetic analysis was performed. To get a confident branch-length, three different trees were inferred: the first for all studied strains, the second for Oceanospirillales order and the third for the other orders. Based on the results, some of the strains were identified with certainty at species level while some others, due to the branch length or the external position, probably belonged to new species. For all other strains identification was possible at genus level only. In many cases this could be due to the scarce informative power of the gene target used to discern the relations below the genus level. Temperature growth profiles The optimal temperatures for growth of the various strains were tested in the range 0-45°C on PCA plates (steps of 5 °C) with optimal NaCl concentration for each strain. Most of the strains (54% ca.) showed the optimum at 30°C. The lowest optimum was recorded at 20°C for two strain only (S8 e S34). None of them showed an optimum above 35°C. The majority of the isolates (64% ca.) showed the optimum in the mesophilic range, but they were also able to grow to 0-5°C. These organisms can be defined as mesophilic-psychrotolerant. Only 3% ca. of the strains showed the optimum at 20°C and growing in the range 5-35°C. These can be defined psychrotrophics. The rest of the isolates (ca. 33%) grew from or above 10°C and showed an optimum amount to 30-35°C. For this reason they can be defined mesophilics. Almost all the strains could be considered as eurythermics, indicating adaptation to wide temperature variations such as those of the water environments of “Saline di Tarquinia”. If compared with the same species described in the literature, the tested strains showed a growth range shifted to lower temperatures, but optima weren’t very different. Salinity growth profiles The optimal salinity for growth of the strains were tested in the range 0-320‰ on PCA plates (steps of 40‰) at 25°C. Approximately 46% of the strains showed an optimum of growth at 40‰ of NaCl and about 23% showed the optimum at 80‰. Most of these strains (ca. 81%) was not able to grow in the absence of NaCl and 22% ca. grew in the presence of salt concentrations equal or greater than 240‰. Among the strains that showed the optimum growth at 40‰ of NaCl, there were some (BS34, S1, S39, S46 and S48) that were able to grow well even in the absence of salt. They could be defined as moderate halophilics normotolerant. Approximately 31% of all strains showed the optimum to 0‰, but were able to tolerate relatively high salt concentrations. These microorganisms can be define halotolerants. Almost all the strains could be considered as euryhaline, indicating adaptation to wide salinity variations such as those of Saline di Tarquinia. If, compared with the same species described in the literature, the strains tested showed a less wide growth range. With regard to the optimum, it would seem to be a good match with the limited data available in the literature. Flow cytometry More detailed information concerning homeostasis and physiological state of each bacterial cell, submitted to different conditions of salinity, was obtained by flow cytometry in the range 0-280‰, with steps of 40‰, for four strains of interest (BS6, S17, S19 and S28). For BS6 and S28 strains, the results obtained by flow cytometry confirmed those obtained with the test of growth on plate. For S17 and S19 strains, the results obtained from the test plate, in which was highlighted growth up to 280‰, although limited from 200‰, were not confirmed. In fact, for S19 strain the growth was manifested up to 200‰ but at the gradual increase in salinity it is possible to notice a proportional increase in the cellular suffering. For S17 strain, the growth stopped at 120‰, showing signs of suffering from the first hours of incubation. This is because the request and the tolerance of salt for many species, varies with growth conditions, such as temperature or composition of medium. The flow cytometry was performed in liquid medium (LB), so there may be differences that affect the growth of the organism. One of the most important is the varying availability of oxygen to which the bacterium is subjected compared to growth on solid medium in the plate. Study on the bacterial communities The bacteria biodiversity was studied by PCR-DGGE fingerprinting of partial 16S-rRNA gene amplicons. DGGE band patterns, representing the various species present in the communities, were compared and clustered using Quantity-One and Phoretix 1D software. A single species is identified by a single band and the relative abundance of a single species is determined by the band intensity. The cluster analysis was performed using the method UPGMA and Dice and Pearson coefficients. From the analysis of the gel it was possible to find a considerable variability in the profiles of fingerprinting, which were not homogeneous neither in the number of bands nor in the distribution of these within the gel. In addition, in the course of several months of sampling, the clusters within the dendrograms were not related to the salinity of the ponds sampled and this has been confirmed also for the summer months, when the largest differences between the values of salinity of the ponds were found. Moreover, it emerged by the clustering analysis that the ponds with high salinity didn’t not present in most of the cases a number of bands less than the other sites during the sampling conducted. To render a graphic representation of the bacterial communities evenness, Pareto-Lorenz distribution curves were drawn based on the intensities of bands in the profiles for three months: August 2012, March 2013 and May 2012, respectively characterized by salinity maximum, minimum and intermediate compared to the whole sample period. The functional community redundancy (response to perturbing environmental conditions) is evaluated by the Functional organization index (Fo) considering curves slope. Results for the months of August and May 2012 (35% and 32% respectively) showed communities with medium-low Fo and a high evenness. In other words, due to the elevated concentration of some species and the availability of many others, the community can potentially deal with environmental conditions changes thus preserving its functionality. These results would seem to adapt to the environment of the solar salterns, characterized by high instability of the environmental parameters that only a community with these features would be able to face. In March 2013 the value was of 43%, therefore due to an increase of the potential physical and chemical properties of the sampled sites, there is also an increase of the functional organization of the community. Pareto-Lorenz distribution curves were drawn also for the first two sampling years for the bacterial community of the vascone pond. The functional organization was very different during the years, therefore there was a high variability in the structure of the community in the time. The Moving Window Analysis was performed to evaluate the changes in the structure of the bacterial community in a single ponds between one month and the next. The variability in the composition of community for the various ponds was very high as highlighted also by the analysis of DGGE gel. Statistical analyses NMDS (No metric multidimensional scaling) NMDS method was performed to search for patterns in the set of biological data (viable and total count, DGGE band matrix and Richness) and to assess their relationship with the environmental data (water salinity and temperature, BOD5, pH, dissolved oxygen and chlorophyll pigments). Looking at the diagrams obtained it was possible to observe that they described a sorting scheme characteristic for each sampled site and this result was confirmed also by NMDS to search for patterns in the set of Biodiversity index (richness, Shannon-Wiener index, Simpson index and evenness) and to assess their relationship with the same environmental data of the previous analysis. Weekly sampling At the end of the monthly sampling, we performed weekly ones for three months in different seasons (May 2014, September 2014 and February 2015). In this way it was possible to obtain a comparison of an additional year of sampling at least for a few months and it was possible to detect even the monthly changes for this environment. The data for the month of February 2015 are still being processed. Weekly sampling have confirmed the results obtained with the monthly sampling. It was highlighted a high variability in the composition of bacterial community among the ponds and, the clusters within the dendrograms do not seem related to the salinity of the sampled ponds. In order to understand the relationships between the bacterial communities of a month over the years of sampling, a combined analysis of the gels was performed for the months of May and September. For these it was possible to perform a comparison for all three years of sampling. The dendrograms related to the similarity of the patterns of bands were calculated using the Dice coefficient and UPGMA algorithm with Phoretix 1D software. Observing both dendrograms it can be seen that, with some exceptions, the ponds group between them according to the date of sampling. Therefore the profiles for the various ponds, taken at the same time, are more similar to each other than the profiles obtained for the same pond in the course of three years. Preliminary study on “Saline di Trapani e Paceco” solar saltern In order to make a comparison with a solar saltern still active in the salt production, we have carried out a preliminary study in the “Salina Chiusicella” of “Saline di Trapani e Paceco” solar saltern. Clustering analysis revealed a substantial difference with the results obtained for the “Saline di Tarquinia”. Looking at the dendrograms in fact, it was possible to detect a clear division into different groupings, in relation to salinity values of the sampled ponds. In addition, during the month of September 2014, although in most cases higher salinities were detected than in the month of September 2013, we could observe a greater number of bands in the fingerprinting profiles and therefore a greater bacterial biodiversity. In both sites, it was not possible to draw any conclusion concerning the trend of the number of OTU varying the salinity in these environments. This confirms the complexity of the change in structure of bacterial communities along the salinity gradient and suggests to revalue the role of the domain bacteria in "extreme" environments. Dottorato di ricerca in Ecologia e gestione delle risorse biologiche
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- 2015
99. Wildlife management in the protected floodplain of the Kopački Rit Nature Park (Croatian Danube Region)
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Ozimec, Siniša, Florijančić, Tihomir, Bošković, Ivica, Fenice, Massimiliano, and Vosniakos, Fokion
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wildlife ,floodplain ,Danube ,Croatia - Abstract
Floodplains are among the most valuable and the most degraded ecosystems in Europe. The Kopački rit Nature Park is situated in northeastern Croatia, between courses of the Danube and the Drava Rivers. The appearance of the whole area and rich biodiversity depends on the flooding regime of the Danube River, while the Drava River has much less importance. This area is protected since 1967, and proclaimed as nature park in 1999 on the surface of 231 km2. In 1993 it is listed among wetlands of international importance(Ramsar area). Tradition of hunting the particular wild animal species: red deer (Cervus elaphus), roe deer (Capreolus capreolus) and wild boar (Sus scrofa) in this part of Croatia dates back more than 300 years. Wildlife management with a purpose of breeding, protection and hunting the game animals is carried out since 1781, when this area was part of the large Belje Estate. Through active management over hundred of years a significant growth in population size of game animals has been achieved, and this area became a hunting resort known all over Europe and the world. Nowadays, wildlife management and hunting activities within the boundaries of the Kopački rit Nature Park are implemented according to Croatian nature protection legislation. Main threats to wildlife management are anthropogenic impact, habitat loss or degradation, more frequent occurrence of extreme weather and hydrological events, and water-borne diseases.
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- 2015
100. The role of the Danube River in spread of the Giant Liverfluke (Facioloides magna) in Croatia
- Author
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Florijančić, Tihomir, Ozimec, Siniša, Bošković, Ivica, Fenice, Massimiliano, and Vosniakos, Fokion
- Subjects
parasitic diseases ,liverfluke ,red deer ,Danube ,Croatia - Abstract
Parasitic diseases are permanently present in wild animals living in natural habitats. The giant liver fluke (Fascioloides magna)is one of the most pathogenic helminths parasitizing a number of mammalian species (primarily ruminants), causing a severe health problems, often leading to death. Specific distribution route of this endoparasite from Central towards Southeast Europe mainly follows the inundation area of the Danube River, where the seasonal migration of red deer (Cervus elaphus) is possible, and intermediate host, a freshwater snail (Lymnaea truncatula) is present. The giant liver fluke was firstly discovered in Croatia in January 2000, during liver examination of red deer hunt in the hunting ground located in the floodplain of the Danube River. It can be confirmed that developmental stages of the giant liver fluke were introduced in Croatia by migration of invaded red deer, and by freshwater snails deposited with floods during the high water-level episodes. Appropriate treatment of parasitic disease has been tried but with limited success. The risk of infection is still present, which was confirmed by dissection of the red deer hind found dead in April 2015, when about 60 liver flukes were taken from the liver. Proper application of zoo-hygienic measures in hunting grounds, combined with antiparasitic treatment of free ranging red deer population and captive deer is important to restrain the further spread of fascioloidosis in Croatia.
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- 2015
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