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Made available in DSpace on 2021-06-25T10:47:04Z (GMT). No. of bitstreams: 0 Previous issue date: 2021-03-01 Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) The combination of different microorganisms and their metabolisms makes the use of microbial consortia in bioremediation processes a useful approach. In this sense, this study aimed at structuring and selecting a marine microbial consortium for Remazol Brilliant Blue R (RBBR) detoxification and decolorization. Experimental design was applied to improve the culture conditions, and metatranscriptomic analysis to understand the enzymatic pathways. A promising consortium composed of Mucor racemosus CBMAI 847, Marasmiellus sp. CBMAI 1062, Bacillus subtilis CBMAI 707, and Dietzia maris CBMAI 705 was selected. This consortium showed 52% of detoxification and 86% of decolorization in the validation assays after seven days of incubation in the presence of 500 ppm of RBBR. Reduction in RBBR color and toxicity were achieved by biosorption and microbial metabolisms. Metatranscriptomic data indicate that the consortium was able to decolorize and breakdown the RBBR molecule using a coordinated action of oxidases, oxygenases, and hydrolases. Epoxide hydrolases and glyoxalases expression could be associated with the decrease in toxicity. The efficiency of this marine microbial consortium suggests their use in bioremediation processes of textile effluents. Departamento de Biologia Geral e Aplicada Instituto de Biociências Universidade Estadual Paulista (UNESP) Centro de Estudos de Insetos Sociais Instituto de Biociências Universidade Estadual Paulista (UNESP) Universidade Estadual de Campinas (UNICAMP) Centro Pluridisciplinar de Pesquisas Químicas Biológicas e Agrícolas Divisão de Recursos Microbianos Departamento de Biologia Geral e Aplicada Instituto de Biociências Universidade Estadual Paulista (UNESP) Centro de Estudos de Insetos Sociais Instituto de Biociências Universidade Estadual Paulista (UNESP) CNPq: 170714/2017–9 FAPESP: 2012/12622–3 FAPESP: 2013/19486–0 FAPESP: 2016/07957–7 FAPESP: 2018/03372–0 FAPESP: 2018/12098–9 CNPq: 303218/2019–3

Made available in DSpace on 2019-10-06T16:37:38Z (GMT). No. of bitstreams: 0 Previous issue date: 2019-08-01 Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) The quaternization of chitosan molecules creates materials with high adsorptive capacity towards textile dyes, which renders them capable of rapidly removing such dyes from a solution. In this study, a novel material was synthesized in bead form to adsorb the Acid Blue 25 textile dye. The adsorption isotherms, kinetics, and thermodynamics of this new material were investigated. The beads were further characterized by FT-IR and SEM studies, as well as their rheological behavior. Bioassays with Daphnia similis analyzed the toxicity of the dye before and after treatments. The Freundlich isotherm model fitted to all the adsorption data in a pH range from 2.50 to 8.50. Kinetic studies showed that adsorption was ruled by an intraparticle diffusion process and reached equilibrium in 270 min, as 39.527 μg mg−1 of dye was sorbed to the beads. Thermodynamic studies showed that adsorption was a spontaneous and endothermic process. Thermodynamics also confirmed that the adsorption was proportionally influenced by higher temperatures. The FT-IR spectroscopy identified the adsorbate/adsorbent binding sites, thus confirming the occurrence of chemisorption. Post-treatment bioassays found a significant decrease in toxicity, obtaining just 10% of D. similis mortality after adsorption treatments. Therefore, the synthesized beads from this research can potentially be applied to the treatment of textile effluents. Department of Biochemistry and Microbiology São Paulo State University (UNESP), 24-A Avenue, 1515 Department of Applied Geology São Paulo State University (UNESP), 24-A Avenue, 1515 Department of Biochemistry and Microbiology São Paulo State University (UNESP), 24-A Avenue, 1515 Department of Applied Geology São Paulo State University (UNESP), 24-A Avenue, 1515 CNPq: 144912/2017-1

Made available in DSpace on 2018-11-26T17:55:32Z (GMT). No. of bitstreams: 0 Previous issue date: 2018-06-01 Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Despite the toxic potential of landfill leachate, some researchers have suggested its use as fertilizer. However, high leachate concentrations can have negative impacts on the environment. Hydrotalcite has been used for the adsorption and purification of effluents. In this study, leachate in its raw and treated (sludge and leachate) forms was subjected to physicochemical, microbiological, toxicity, and biodegradability analyses. Treatment with hydrotalcite produced good results regarding the removal of conductivity (51%), turbidity (58%), biochemical oxygen demand in 5 d (95%), boron (40%), ammonia (35%), chemical oxygen demand (43%), color (70%), total coliforms, and Escherichia coli, but did not remove sodium or chloride and led to an increase in pH. Treatment led to a 21.63% decrease in toxicity to Artemia sp. and a 42% decrease in toxicity to Lactuca sativa seeds. The raw and treated leachate in the soil inhibited the germination and development of L. sativa by 12% and 5%, respectively, in comparison with the control. Landfill leachate at a concentration of 50 m(3)/ha initially potentiated bacterial growth and inhibited fungal growth. The microbiota stabilized after 84 d, except in the high concentration trials, in which the inhibition of fungal growth continued. The analyses of the landfill leachate at a concentration of 200 m(3)/ha revealed that repeated fertilization could make the soil unviable for planting. The raw leachate at the two concentrations tested was toxic to Daphnia similis. The sludge at a concentration of 2.5% stimulated the growth of L. sativa and increased its biomass by 42% in comparison with the control, with no negative impact on the soil microbiota or toxicity to D. similis. The biodegradation test showed that the inoculum increased the average daily efficiency of the process. Despite the efficient biodegradation (50% in 24 h), the toxic potential of the leachate was not eliminated. Moreover, respirometry proved not to be an effective method for the determination of the biodegradation of the sludge, since the system is influenced by the chemical characteristics of hydrotalcite. Univ Estadual Paulista UNESP, Dept Biochem & Microbiol, Inst Biosci, Av 24A,1515 Bela Vista, BR-13506900 Rio Claro, SP, Brazil Univ Estadual Paulista UNESP, Inst Geosci & Exact Sci, Ctr Environm Studies CEA, Av 24A,1515 Bela Vista, BR-13506900 Rio Claro, SP, Brazil Univ Estadual Paulista UNESP, Dept Biochem & Microbiol, Inst Biosci, Av 24A,1515 Bela Vista, BR-13506900 Rio Claro, SP, Brazil Univ Estadual Paulista UNESP, Inst Geosci & Exact Sci, Ctr Environm Studies CEA, Av 24A,1515 Bela Vista, BR-13506900 Rio Claro, SP, Brazil

Actually, the most used method to control ticks is synthetic acaricides with neuro- toxic action. However, the use of these methods presents inconveniences, such as the contamina- tion of the environment and risks to the host's health due to the residual effects. Thus, several studies have been developed aiming to fi nd alternative ways to control these ectoparasites, such as the use of natural compounds with active ingredients, which act controlling some species of plagues in addition to presenting medicinal properties that are beneficial to humans. The pres- ent study aimed to analyze the action of andiroba oil (Carapa guianensis) on the synganglion of Rhipicephalus sanguineus semiengorged females through morphological and cytochemical tech- niques aiming to verify if this natural product have neurotoxic action as the numerous synthetic acaricides. The results showed that andiroba oil interferes in the synganglion through structural and enzymatic changes, which lead the nervous tissue to apoptotic death involving autophagy. Among these changes was observed the emergence of large empty spaces between the perineu- rium and the cortical region, vacuolated cortex cells and with cell swelling, neural cells with pic- notic nuclei or in initial stage of chromatin margination and neuropile with high structural disorganization. Considering these data, it can be concluded that andiroba seed oil can be used as an alternative method in the control of R. sanguineus ticks due to its neurotoxic action. Microsc. Res. Tech. 00:000-000, 2013. V C 2013 Wiley Periodicals, Inc.

KEY WORDS ticks; natural product; germ cells; cytotoxicity; reproductive efficiency indexABSTRACT Because of the increasing medical-veterinary importance of ticks, the developmentof alternative control methods, less aggressive to the host and the environment has become the tar-get of several researches. In this sense, the present study analyzed the action of different concen-trations (5, 10, and 20%) of andiroba seed oil (Carapa guianensis) on the reproductive system ofRhipicephalus sanguineus females, through histochemical techniques and the quantification of thereproductive efficiency index. The results showed that andiroba oil is a potent natural agent, ableto cause several changes in the oocytes of this species, impairing the reproductive success, oncethis natural product induces great physiological changes in the oocytes in all development stages,such as drastic reduction in proteins, polysaccharides, and lipids in these cells, and these compo-nents are essential for the viability of the embryo. In addition, it was observed that this productstimulate the oviposition, mainly at the concentration of 20%. This higher production of eggs repre-sents a defense mechanism developed by the organism in order to ensure the reproductive successof the species, even in the presence of the toxic agent. However, the results obtained suggested thatthe laid eggs would not be viable, due to the great changes undergone by the oocytes. Thus, thepresent study showed that the use of this vegetal product would be an alternative way to controlthe ticks, bringing benefits similar to the ones obtained through the use of synthetic acaricides;however, with less damage to nontarget organisms and the environment as well. Microsc. Res.Tech. 00:000–000, 2012.

The present study performed an analysis of the ultrastructural changes induced by andiroba seed oil in the synganglion of Rhipicephalus sanguineus female ticks, aiming to provide scientific grounds to help in the creation of more specific and efficient methods of control. The synganglion consists of a mass of fused nerves externally covered by the neural lamella, a uniform and acellular layer. Just below, the perineurium is found, formed by glial cells. Internally, the synganglion is subdivided into an outer cortical region (cortex), which contains the cellular bodies of the neural cells and an inner region, the neuropile, formed by a set of nerve fibers (extensions of the neural cells). The results showed that the synganglion of females exposed to andiroba oil showed structural changes, such as: irregular and apparently thinner neural lamella, perineurium glial cells presenting large cytoplasmic vacuoles, decrease in the extensions of glial cells, separation of cortex cells, which were formerly attached through their membranes, neural cells presenting irregular plasma membranes and cytoplasm with autophagic vacuoles and mitochondria with disorganized cristae and in process of degeneration. This study confirmed the neurotoxic action of the andiroba oil, which would probably be able to impair the neural functions. Thus, it is suggested that this product has the potential to be used as an alternative method to control ticks.

Research for acaricides with lower toxicity and impact on the environment has been intensified. An alternative would be the use of natural compounds or of synthetic products in lower concentrations than the ones sold commercially. Thus, this study describes the action of andiroba seed oil on the nuclei of the ovary and synganglion cells of Rhipicephalus sanguineus, and presents an analysis of the nuclear morphology of the nervous system cells of this tick species when exposed to permethrin. The results obtained showed that, although no changes have been observed in the genetic material of the ovary cells exposed to the andiroba oil, this compound, as well as permethrin, has neurotoxic action on the females of this species. The damages caused to the physiology of the synganglion, due to the loss of integrity of the genetic material, would result in the impairment of the metabolism of other systems of R. sanguineus ticks.

Actually, the most used method to control ticks is synthetic acaricides with neurotoxic action. However, the use of these methods presents inconveniences, such as the contamination of the environment and risks to the host's health due to the residual effects. Thus, several studies have been developed aiming to find alternative ways to control these ectoparasites, such as the use of natural compounds with active ingredients, which act controlling some species of plagues in addition to presenting medicinal properties that are beneficial to humans. The present study aimed to analyze the action of andiroba oil (Carapa guianensis) on the synganglion of Rhipicephalus sanguineus semiengorged females through morphological and cytochemical techniques aiming to verify if this natural product have neurotoxic action as the numerous synthetic acaricides. The results showed that andiroba oil interferes in the synganglion through structural and enzymatic changes, which lead the nervous tissue to apoptotic death involving autophagy. Among these changes was observed the emergence of large empty spaces between the perineurium and the cortical region, vacuolated cortex cells and with cell swelling, neural cells with picnotic nuclei or in initial stage of chromatin margination and neuropile with high structural disorganization. Considering these data, it can be concluded that andiroba seed oil can be used as an alternative method in the control of R. sanguineus ticks due to its neurotoxic action.

The present study performed an analysis about the effects of andiroba seed oil (Carapa guianensis) in the ovary of Rhipicephalus sanguineus semi-engorged females; once, there are few studies about the action of natural products on the reproductive system, a vital organ for the biological success of this animal group. The results showed that andiroba oil is a potent natural agent which causes significant structural changes in the oocytes, such as the emergence of large vacuolated cytoplasmic regions, reduction in the number of yolk granules, changes in the shape of the cells, as well as impairment of genetic material. In addition, the ovary epithelium showed severe morphological changes, such as extreme structural disorganization, with highly vacuolated cells and picnotic nuclei, forming an amorphous mass. This study showed also that oocytes (mainly in the initial stages of development) and the ovary epithelium of R. sanguineus females subjected to different concentrations of andiroba oil presented morphological changes which became more numerous and intense as the concentration of the product increased. Based on the results, it can be inferred that although the defense mechanisms are developed by oocytes to recover the cellular integrity (presence of autophagic vacuoles), these cells are not able to revert the damage caused by this product. Thus, it can be concluded that although the damages caused to the oocytes by andiroba oil are comparatively less severe than the ones caused by synthetic acaricides, this product can be considered a potent natural agent that reduce and/or prevent the reproduction of R. sanguineus females, with the advantage of not causing environmental impact such as synthetic chemical acaricides.

Made available in DSpace on 2018-12-11T17:04:11Z (GMT). No. of bitstreams: 0 Previous issue date: 2016-01-01. Added 1 bitstream(s) on 2019-10-09T18:30:29Z : No. of bitstreams: 1 S0104-14282016000200161.pdf: 1525549 bytes, checksum: 69e6f87d0484aa265bf636c936d9c442 (MD5) There is considerable concern about the impact plastic materials have on the environment due to their durability and resistance to degradation. The use of pro-oxidant additives in the polymer films could be a viable way to decrease the harmful effects of these discarded materials. In this study, films of PHBV/PP-co-PE (80/20 w/w) and PHBV/PP-co-PE/add (80/19/1 w/w/w) (with pro-oxidant additive) were employed to verify the influence of the additive on the biodegradation of these films in the soil. These films were obtained by melting the pellets in a press at 180 °C which were buried in soil columns for 3 and 6 months. Some samples were also heated before being buried in soil. The biodegradation is higher for the additive blend buried for 3 months than for the pre-heated blend. After 6 months the blend buried and heated/buried was completely degraded in soil. The effect of the additive, on chain oxidation, is more time-dependant than heat-dependant. Polymer Treatment Laboratory-LTP Biochemistry and Microbiology Department Universidade Estadual Paulista - UNESP National Nanotechnology Laboratory for Agriculture - LNNA Embrapa Instrumentação - EMBRAPA Polymer Treatment Laboratory-LTP Biochemistry and Microbiology Department Universidade Estadual Paulista - UNESP