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Soil contamination constitutes a significant threat to the health of soil ecosystems in terms of complexity, toxicity, and recalcitrance. Among all contaminants, aliphatic petroleum hydrocarbons (APH) are of particular concern due to their abundance and persistence in the environment and the need of remediation technologies to ensure their removal in an environmentally, socially, and economically sustainable way. Soil remediation technologies presently available on the market to tackle soil contamination by petroleum hydrocarbons (PH) include landfilling, physical treatments (e.g., thermal desorption), chemical treatments (e.g., oxidation), and conventional bioremediation. The first two solutions are costly and energy-intensive approaches. Conversely, bioremediation of on-site excavated soil arranged in biopiles is a more sustainable procedure. Biopiles are engineered heaps able to stimulate microbial activity and enhance biodegradation, thus ensuring the removal of organic pollutants. This soil remediation technology is currently the most environmentally friendly solution available on the market, as it is less energy-intensive and has no detrimental impact on biological soil functions. However, its major limitation is its low removal efficiency, especially for long-chain hydrocarbons (LCH), compared to thermal desorption. Nevertheless, the use of fungi for remediation of environmental contaminants retains the benefits of bioremediation treatments, including low economic, social, and environmental costs, while attaining removal efficiencies similar to thermal desorption. Mycoremediation is a widely studied technology at lab scale, but there are few experiences at pilot scale. Several factors may reduce the overall efficiency of on-site mycoremediation biopiles (mycopiles), and the efficiency detected in the bench scale. These factors include the bioavailability of hydrocarbons, the selection of fungal species and bulking agents and their application rate, the interaction between the inoculated fungi and the indigenous microbiota, soil properties and nutrients, and other environmental factors (e.g., humidity, oxygen, and temperature). The identification of these factors at an early stage of biotreatability experiments would allow the application of this on-site technology to be refined and fine-tuned. This review brings together all mycoremediation work applied to aliphatic petroleum hydrocarbons (APH) and identifies the key factors in making mycoremediation effective. It also includes technological advances that reduce the effect of these factors, such as the structure of mycopiles, the application of surfactants, and the control of environmental factors. [ABSTRACT FROM AUTHOR]

Conventionally, the commercial supply of chitin and chitosan relies on shellfish wastes as the extraction sources. However, the fungal sources constitute a valuable option, especially for biomedical and pharmaceutical applications, due to the batch-to-batch unsteady properties of chitin and chitosan from conventional ones. Fungal production of these glycans is not affected by seasonality enables accurate process control and, consequently, more uniform properties of the obtained product. Moreover, liquid and solid production media often are derived from wastes, thus enabling the application of circular economy criteria and improving the process economics. The present review deals with fungal chitosan production processes focusing on waste-oriented and integrated production processes. In doing so, contrary to other reviews that used a genus-specific approach for organizing the available information, the present one bases the discussion on the bioprocess typology. Finally, the main process parameters affecting chitosan production and their interactions are critically discussed. [ABSTRACT FROM AUTHOR]

The genus Aspergillus encompasses several species with relevant lignocellulose-degrading capacity, and a novel species, denominated A. olivimuriae, was recently discovered after its isolation from table olive brine. The acquisition of insight into this species and the assessment of its potential relied on a bioinformatics approach, based on the CAZy database, associated with enzymatic activity profiles in solid-state cultures on four different types of waste, including residual thistle biomass (RTB), spent coffee grounds (SCG), digestate solid fraction and barley straw. The CAZy analysis of A. olivimuriae genome showed that the number of predicted genes for each family was close to that of other Aspergillus species, except for cellobiose dehydrogenase, acetyl xylan esterase and polygalacturonases. In A. olivimuriae solid-state cultures, hemicellulose degradation outperformed that of cellulose, and lignin removal did not occur, regardless of the growth substrate. This is in line with its CAZy content and the extent of hemicellulolytic, and ligninolytic activities detected in its solid-state cultures. RTB and barley straw were the substrates enabling the best glycosyl hydrolase production levels. The exception was SCG, the hemicellulose composition of which, mainly made of glucomannans and galactomanans, led to the highest β-mannanase and β-mannosidase production levels (3.72 ± 0.20 and 0.90 ± 0.04 IU g−1 substrate, respectively). [ABSTRACT FROM AUTHOR]

Pleurotus ostreatus dual biofilms with bacteria are known to be involved in rock phosphate solubilization, endophytic colonization, and even in nitrogen fixation. Despite these relevant implications, no information is currently available on the architecture of P. ostreatus -based dual biofilms. In addition to this, there is a limited amount of information regarding the estimation of the temporal changes in the relative abundances of the partners in such binary systems. To address these issues, a dual biofilm model system with this fungus was prepared by using Pseudomonas alcaliphila 34 as the bacterial partner due to its very fast biofilm-forming ability. The application of the bacterial inoculum to already settled fungal biofilm on a polystyrene surface coated with hydroxyapatite was the most efficient approach to the production of the mixed system the ultrastructure of which was investigated by a multi-microscopy approach. Transmission electron microscopy analysis showed that the adhesion of bacterial cells onto the mycelial cell wall appeared to be mediated by the presence of an abundant layer of extracellular matrix (ECM). Scanning electron microscopy analysis showed that ECM filaments of bacterial origin formed initially a reticular structure that assumed a tabular semblance after 72 h, thus overshadowing the underlying mycelial network. Across the thickness of the mixed biofilms, the presence of an extensive network of channels with large aggregates of viable bacteria located on the edges of their lumina was found by confocal laser scanning microscopy; on the outermost biofilm layer, a significant fraction of dead bacterial cells was evident. Albeit with tangible differences, similar results regarding the estimation of the temporal shifts in the relative abundances of the two partners were obtained by two independent methods, the former relying on qPCR targeting of 16S and 18S rRNA genes and the latter on ester-linked fatty acid methyl esters analysis. [ABSTRACT FROM AUTHOR]

BACKGROUND: Stevensite and biochar were investigated to covalently immobilize laccase from Myceliophthora thermophila (MtL) and Pleurotus eryngii (PeL) through the sequential application of aminopropyltriethoxysilane and glutaraldehyde. The immobilized preparations were tested to remove three tetracyclines and six sulfonamides at 0.1 mmol L−1 of each antibiotic. Degradation experiments were conducted both in the absence and in the presence (0.2 mmol L−1) of ABTS, 1‐hydroxybenzotriazol (HBT), syringaldehyde or violuric acid. The residual antibiotic activity was tested towards five bacterial species and a bacterial consortium from wastewater. RESULTS: Higher values of activity yields (74% and 70.3%) and catalytic capabilities (1426 and 1405 IU g−1) were obtained with PeL on stevensite and biochar than with MtL. Stevensite enabled higher reusability and storage stability than biochar. Best removals of tetracyclines and sulfonamides were obtained with immobilized‐laccase systems coupled to ABTS or syringaldehyde. Immobilized‐laccase/ABTS systems removed 100% of tetracyclines while only chlortetracycline was completely removed in the presence of syringaldehyde. With ABTS, the most effectively removed sulfonamides were sulfathiazole and sulfadiazine (up to 100% and 54%), while syringaldehyde best supported the removal of sulfanilamide, sulfamethazine and sulfamethoxazole (up to 42%, 45% and 46%, respectively). In some cases, an effective antibiotics removal led to either low or no residual antibiotic activity. CONCLUSION: MtL and PeL were immobilized successfully on biochar and stevensite. The addition of either ABTS or syringaldehyde enhanced significant removals, up to 100%, of tetracyclines and sulfonamides by the immobilized laccase systems. Noteworthy, biochar‐immobilized laccases/ABTS led to complete suppression of the antibiotic activity of tetracyclines. © 2018 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Microbial oils are regarded as a sustainable alternative to vegetable oils for biodiesel manufacturing. However, in order to develop a cost-effective process, high-lipid producer microorganisms should be combined with low-cost renewable growth substrates. For this reason, the objective of the present study was to assess comparatively the oil-producing performance of 9 oleaginous fungi belonging to the Aspergillus, Mucor, Mortierella and Cunninghamella genera on three relevant and widespread waste, such as glycerol, orange peel extract (OPE) and ricotta cheese whey (RCW). This screening was performed at the shaken flask level and, among the strains under study, Mortierella isabellina NRRL 1757 turned out to be the most efficient and versatile and its lipid profile was found to be highly compatible with biodiesel production. Process transfer of M. isabellina lipid production to the lab-scale Stirred Tank Reactor on all the three waste-based media, was shown to be feasible, achieving a lipid productivity of 0.46, 1.24 and 0.91 g/(L d) on glycerol, OPE and RCW, respectively. Noteworthy, the fatty acid analysis of the oils produced, confirmed their suitability for biodiesel manufacturing, exhibiting a high similarity to palm and Jatropha oils commonly used as feedstock for this production. [ABSTRACT FROM AUTHOR]

According to EU Strategy for the Baltic Sea Region, Lithuania obligates to ensure sustainable growth, gain and maintain good condition of marine environment until 2020. In accordance with the sustainability approach, every potential cost and energy cutting as well as social sustainability measure for wastewater treatment should be explored. Nonetheless, Lithuania wastewater treatment plants (WWTP) in the sustainability context have never been evaluated before. A comprehensive set of 30 sustainable development indicators (SDI) (9 functional, 11 environmental, 5 economical and 6 socio-cultural) in connection with functional unit were applied to medium-sized Jurbarkas WWTP (with a capacity of 2,540 m³/d). Sustainability evaluation involved life cycle of WWTP maintenance phase as well as water inlet, outlet and manufacturing. Results revealed that in the general context of sustainability the stability of plant varied greatly. Nine SDI haven't reached the sustainability approach. Graphically systemized results in the four sustainability categories have shown that relatively highest environmental impact regarding the maximum covered plot is caused due to an economical unsustainability. Operational and maintenance costs per volume of wastewater treated were approximately 2.23 higher than the cost to consumers per one cubic meter of wastewater treated, therefore depreciation, repairs, material costs and wastewater treatment costs accounted to 87%. Methodology by using SDI for estimating sustainability of WWTP is adaptable to different capacity or technology of WWTP, comparable, simple to develop and improve. [ABSTRACT FROM AUTHOR]

Naphthenic acids (NAs) are an important group of toxic organic compounds naturally occurring in hydrocarbon deposits. This work shows that Rhodococcus aetherivorans BCP1 cells not only utilize a mixture of eight different NAs (8XNAs) for growth but they are also capable of marked degradation of two model NAs, cyclohexanecarboxylic acid (CHCA) and cyclopentanecarboxylic acid (CPCA) when supplied at concentrations from 50 to 500 mgL-1. The growth curves of BCP1 on 8XNAs, CHCA, and CPCA showed an initial lag phase not present in growth on glucose, which presumably was related to the toxic effects of NAs on the cell membrane permeability. BCP1 cell adaptation responses that allowed survival on NAs included changes in cell morphology, production of intracellular bodies and changes in fatty acid composition. Transmission electron microscopy (TEM) analysis of BCP1 cells grown on CHCA or CPCA showed a slight reduction in the cell size, the production of EPS-like material and intracellular electrontransparent and electron-dense inclusion bodies. The electron-transparent inclusions increased in the amount and size in NA-grown BCP1 cells under nitrogen limiting conditions and contained storage lipids as suggested by cell staining with the lipophilic Nile Blue A dye. Lipidomic analyses revealed significant changes with increases of methyl-branched (MBFA) and polyunsaturated fatty acids (PUFA) examining the fatty acid composition of NAs-growing BCP1 cells. PUFA biosynthesis is not usual in bacteria and, together with MBFA, can influence structural and functional processes with resulting effects on cell vitality. Finally, through the use of RT (Reverse Transcription)- qPCR, a gene cluster (chcpca) was found to be transcriptionally induced during the growth on CHCA and CPCA. Based on the expression and bioinformatics results, the predicted products of the chcpca gene cluster are proposed to be involved in aerobic NA degradation in R. aetherivorans BCP1. This study provides first insights into the genetic and metabolic mechanisms allowing a Rhodococcus strain to aerobically degrade NAs. [ABSTRACT FROM AUTHOR]

The increasing demand of plant oils for biodiesel production has highlighted the need for alternative strategies based either on non-food crops or agro-industrial wastes that do not compete with food and feed production. In this context, the combined use of wastewater and oleaginous microorganisms could be a valuable production option. Ricotta cheese whey (RCW), one of the major byproducts of the dairy industry, is produced in very high and steadily increasing amounts and, due to its high organic load, its disposal is cost-prohibitive. In the present study, in order to assess the adequacy of RCW as a growth medium for lipid production, 18 strains of oleaginous yeasts were investigated in shaken flask for their growth and lipid-producing capabilities on this substrate. Among them, Cryptococcus curvatus NRRL Y-1511 and Cryptococcus laurentii UCD 68-201 adequately grew therein producing substantial amounts of lipids (6.8 and 5.1 g L − 1 , respectively). A high similarity between the percent fatty acid methyl esters (FAME) composition of lipids from the former and the latter strain was found with a predominance of oleic acid (52.8 vs. 48.7%) and of total saturated fatty acids (37.9 vs. 40.8%). The subsequent scale transfer of the C. laurentii UCD 68-201 lipid production process on RCW to a 3-L STR led to significantly improved biomass and total lipid productions (14.4 and 9.9 g L − 1 , respectively) with the biodiesel yield amounting to 32.6%. Although the C. laurentii FAME profile was modified upon process transfer, it resembled that of the Jatropha oil, a well established feedstock for biodiesel production. In conclusion, C. laurentii UCD 68-201, for which there is very limited amount of available information, turned out to be a very promising candidate for biodiesel production and wide margins of process improvement might be envisaged. [ABSTRACT FROM AUTHOR]

This study investigated the individual and interactive effects of three factors - temperature, inoculum/substrate ratio (ISR) and inoculum typology - on the anaerobic digestion of corn ethanol distillery wastewater. Biochemical methane potential assays planned with factorial design with two independent quantitative variables on three levels (ISR: 1:1, 2:1 and 3:1; temperature: 30°C, 33.5°C, 37°C) and one independent qualitative variable (inoculum type: suspended, granular, mixed) have been performed. Response Surface Methodology has been used to study the effect of the factors with the aim of maximizing the specific methane yields (Y) obtainable with this substrate. The results show that all three investigated factors influence in a significant matter the Y, the ISR having the strongest effect on it. The temperature has significant influence on the Y only in combination with high ISR values. The optimal conditions for the maximum Y (551 mL CH g VS) have been found at 37°C operating temperature, ISR=3:1 and using granular inoculum. These conditions gave rise to a 4-fold increase of Y with respect to the worst combination of factors (Y=129 mL g VS for the suspended inoculum type, at 30°C and ISR=1:1). The results improve the knowledge on the digestion of this substrate, providing information for successful process up-scaling. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

Abstract: An experimental biofuel wood chip storage site was studied, as a potential fungal “reservoir,” by means of quantitative and qualitative assessments of airborne fungal spores. Fungal load in the bio-aerosol, determined through active and passive methods, declined with the distance from wood piles. Occupational exposure was comparatively evaluated when two specific operational tasks, manual and mechanized handling, were performed. Under the conditions tested, the manual operators were more exposed to the airborne fungal spores (4864 ± 580 CFU m−3 air). The collected spores were identified as belonging to species of the genera Alternaria, Aspergillus, Penicillium, Fusarium, Cladosporium, Pleospora, Cochliobolus, Epicoccum, Absidia, and Trichoderma. Most prevalent were the genera Alternaria and Cladosporium, with the highest percentages of occurrence (30 and 12%, respectively). To the best of our knowledge, this is the first work reporting the identification through molecular methods of airborne fungi released during the handling of wood chip biofuel biomass. [Copyright &y& Elsevier]

Fungal strains naturally occurring on the wood and leaves of the salt-excreting desert tree Tamarix were isolated and characterized for their ability to produce cellulose- and starch-degrading enzymes. Of the 100 isolates, six fungal species were identified by ITS1 sequence analysis. No significant differences were observed among taxa isolated from wood samples of different Tamarix species, while highly salt-tolerant forms related to the genus Scopulariopsis (an anamorphic ascomycete) occurred only on the phylloplane of T. aphylla. All strains had cellulase and amylase activities, but the production of these enzymes was highest in strain D, a Schizophyllum-commune-related form. This strain, when grown on pretreated Tamarix biomass, produced an enzymatic complex containing levels of filter paperase (414 ± 16 IU/ml) that were higher than those of other S. commune strains. The enzyme complex was used to hydrolyze different lignocellulosic substrates, resulting in a saccha-rification rate of pretreated milk thistle (73.5 ± 1.2 %) that was only 10 % lower than that obtained with commercial cellulases. Our results support the use of Tamarix biomass as a useful source of cellulolytic and amylolytic fungi and as a good feedstock for the economical production of commercially relevant cellulases and amylases. [ABSTRACT FROM AUTHOR]

In this study a combination of both molecular and biochemical methods have been used to characterize the bacterial microbiota in water and sediment of a saline lake in Transylvania. The physicochemical characterization of the water samples from different lake depths indicated a stratification of the lake that affects the distribution of resident microorganisms, confirmed also by the significant differences in terms of functional diversity of the microbial communities in different water layers. The superficial bacterial community shows a good oxidative capability, degrading a wide range of organic substrates, yet the bottom layer community exhibits a major level of specialization. The membrane fatty acid analysis of the sediment bacterial community shows the prevalent presence of Gram negative bacteria, confirmed by the culturing techniques. Among the 24 collected isolates, 16S rRNA gene sequencing analysis permitted to identify 10 different species, belonging toBacillus,Halomonas,Idiomarina, Marinobacter, Pseudoalteromonas, Salinivibrio, Staphylococcusgenera and prevalently classified as halophiles. [ABSTRACT FROM PUBLISHER]

Usage of ultrasonic field-based filters in retention of filamentous fungal cells was assessed using Rhizopus arrhizus NRRL 1526 as a model organism. Effects of operating conditions, such as power input, harvest pump flow rate, run time and stop time, on the system''s separation efficiency (SE) were evaluated by modulating the variables according to a Central Composite Design (CCD). The standard pump with which the ultrasonic filter was equipped was shown to be unsuitable and was, therefore, substituted for with a prime rate reverse pump that made possible separation and recycle of the mycelial biomass. The operating conditions were optimised (run time, 300 s; stop time, 3 s; power input, 6 W; harvest pump flow rate, 4 l per day) and a repeated batch process (three batches for a total of 192 h) was performed during which the SE was maintained always higher than 88%. [Copyright &y& Elsevier]

Antimicrobial peptides (AMPs) are short peptides active against a wide range of pathogens and, therefore, they are considered a useful alternative to conventional antibiotics. We have identified a new AMP in a transcriptome derived from the Antarctic fish Trematomus bernacchii. This peptide, named Trematocine, has been investigated for its expression both at the basal level and after in vivo immunization with an endemic Antarctic bacterium (Psychrobacter sp. TAD1). Results agree with the expected behavior of a fish innate immune component, therefore we decided to synthesize the putative mature sequence of Trematocine to determine the structure, the interaction with biological membranes, and the biological activity. We showed that Trematocine folds into a α-helical structure in the presence of both zwitterionic and anionic charged vesicles. We demonstrated that Trematocine has a highly specific interaction with anionic charged vesicles and that it can kill Gram-negative bacteria, possibly via a carpet like mechanism. Moreover, Trematocine showed minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) values against selected Gram-positive and Gram-negative bacteria similar to other AMPs isolated from Antarctic fishes. The peptide is a possible candidate for a new drug as it does not show any haemolytic or cytotoxic activity against mammalian cells at the concentration needed to kill the tested bacteria. [ABSTRACT FROM AUTHOR]

The editors would like to express their sincere gratitude to the following reviewers for their precious time and dedication, regardless of whether the papers were finally published: Peer review is the driving force of journal development, and reviewers are gatekeepers who ensure that I Applied Sciences i maintains its standards for the high quality of its published papers. [Extracted from the article]

Fenton-like treatment (FLT) is an ISCO technique relying on the iron-induced H 2 O 2 activation in the presence of additives aimed at increasing the oxidant lifetime and maximizing iron solubility under natural soil pH conditions. The efficacy of FLT in the clean-up of hydrocarbon-contaminated soils is well established at the field-scale. However, a better assessment of the impact of the FLT on density, diversity and activity of the indigenous soil microbiota, might provide further insights into an optimal combination between FLT and in-situ bioremediation (ISB). The aim of this work was to assess the impacts of FLT on the microbial community of a diesel-contaminated soil collected nearby a gasoline station. Different FLT conditions were tested by varying either the H 2 O 2 concentrations (2 and 6%) or the oxidant application mode (single or double dosage). The impact of these treatments on the indigenous microbial community was assessed immediately after the Fenton-like treatment and after 30, 60 and 90 d and compared with enhanced natural attenuation (ENA). After FLT, a dramatic decrease in bacterial density, diversity and functionality was evident. Although in microcosms with double dosing at 2% H 2 O 2 a delayed recovery of the indigenous microbiota was observed as compared to those subjected to single oxidant dose, after 60 d incubation the respiration rate increased from 0.036 to 0.256 μg C CO 2 g −1 soil h −1 . Irrespective of the oxidant dose, best degradation results after 90 d incubation (around 80%) were observed with combined FLT, relying on double oxidant addition, and bioremediation. [ABSTRACT FROM AUTHOR]

Arundo donax L. has received much attention from researchers as biomass crop because of its vigorous growth, high productivity and low agronomic inputs requirements. Once harvested, the chopped biomass of A. donax L. may be stored for a variable period according to energy demand or logistic reasons. As consequence of storage, the chopped biomass may undergo processes of degradation that can compromise the energy yield of the product and the economic convenience of the cultivation. In the view of preserving the A. donax L. biomass for producing different kind of energy, such as bio-ethanol, biogas, and fuel for combustion, the aim of this study was to investigate, in small-scale, different storage systems assessing the dynamics of storage and their effects on energy losses and fuel quality. The work has included different studies, such as (i) the monitoring of heat development, moisture content and dry matter losses, (ii) the analysis of polymeric compounds and combustion performances. Results indicate that according to the storage method adopted, the conservation of the product can be significantly influenced, with clear impacts on its energy potential. Polymeric composition changed after storage according to the method used, while energetic characteristics were not remarkably affected. [ABSTRACT FROM AUTHOR]

The Bronze Age archaeological site of Shahr-i Sokhta (30° 39′ N; 61° 24’ E), located today in southeastern Iran, Sistan region, is a special archaeological deposit in which the exceptional preservation of human, plant and animal remains, due to the dry climate of the region, can provide detailed information on one of the first complex proto-urban societies. In recent years, there has been growing interest in changes in local climate and environment as major reasons why the settlement was abandoned about 4000 years ago. Food shortage has been regarded as a direct effect of these changes. No attention has been paid to the potential health hazards associated with ancient urban/domestic pollution, although large garbage deposits have been found in several parts of the site. During excavations in 2007, four soil samples were taken under aseptic conditions at a depth of 1.5–2 m in a stratified deposit sealed by the floor of a small house, dated to the second half of the third millennium BC. Microbiological, palynological, carpological and microanalytical studies were performed on the four soil samples. Site C was identified as the most affected by human activity. Failure of conventional methods of detecting culturable and unculturable microbes in site C indicated the need for specific culture conditions suggested by palynological observations. Since oat seed residues were identified among the archaeobotanical material, oat bran was used as carbon and energy source to make a new medium to revive microbes. Coarsely ground oat bran was sterilized twice and soaked with minimal medium as sole carbon source. About 50 mg of buried soil from site C was added to the medium in cell culture flasks with aerobic and anaerobic stoppers and incubated at 28–30 °C and at 4 °C. After incubation under aerobic and anaerobic conditions, five sporogenic microbes were identified by sequencing 16S rDNA and ITS rRNA regions: a sporogenic strain IRC3 identified as Bacillus sp. was the only isolate under anaerobic conditions, whereas under aerobic conditions four moulds were isolated: Aspergillus flavus IRC1, Penicillium crysogenum IRC2, Cladosporium sp. IRC4, and the psychrotroph Aspergillus restrictus IRC5. Bacillus sp., with 99.7% similarity to Bacillus subtilis , broke down oat bran, producing a gel, while Cladosporium sp., with 99.8% similarity to Cladosporium sphaerospermium, grew on oat bran by synthesizing intracellular lipids. All these microbes are known to spoil food and they are common where there is intense human activity. [ABSTRACT FROM AUTHOR]

Different applications of spent Agaricus bisporus substrate (SAS), a widespread agro-industrial waste, were investigated with respect to the remediation of a historically polluted soil with Polycyclic Aromatic Hydrocarbons (PAH). In one treatment, the waste was sterilized (SSAS) prior to its application in order to assess its ability to biostimulate, as an organic amendment, the resident soil microbiota and ensuing contaminant degradation. For the other treatments, two bioaugmentation approaches were investigated; the first involved the use of the waste itself and thus implied the application of A. bisporus and the inherent microbiota of the waste. In the second treatment, SAS was sterilized and inoculated again with the fungus to assess its ability to act as a fungal carrier. All these treatments were compared with natural attenuation in terms of their impact on soil heterotrophic and PAH-degrading bacteria, fungal growth, biodiversity of soil microbiota and ability to affect PAH bioavailability and ensuing degradation and detoxification. Results clearly showed that historically PAH contaminated soil was not amenable to natural attenuation. Conversely, the addition of sterilized spent A. bisporus substrate to the soil stimulated resident soil bacteria with ensuing high removals of 3-ring PAH. Both augmentation treatments were more effective in removing highly condensed PAH, some of which known to possess a significant carcinogenic activity. Regardless of the mode of application, the present results strongly support the adequacy of SAS for environmental remediation purposes and open the way to an attractive recycling option of this waste. [ABSTRACT FROM AUTHOR]

Highlights: [•] Antarctic fungus Lecanicillium muscarium chitinase production studied on shrimp and crab wastes. [•] The fungus produced quite high levels of enzymes on shrimp wastes. [•] Production of enzymes was optimized in bioreactor by RSM. [•] Optimized bioprocess in bioreactor yielded 137% more than that in shaken flasks. [•] Two cold-tolerant chitinolytic enzymes were purified and characterized. [ABSTRACT FROM AUTHOR]

Abstract: Nineteen bacterial isolates were grown in shaken cultures in media containing chitin as carbon source and different additional nitrogen sources such as yeast nitrogen base (YNB), yeast extract (YE), corn steep liquor (CSL) and ammonium sulfate. Strain BM17 showed the highest activity (200U/l) in medium containing Chitin (1%) and YNB (0.5%). Molecular analysis of the 16S rRNA gene showed that strain BM17 belongs to the species Paenibacillus pabuli (99.72% homology). The enzyme activity started after 12–24h; exponential enzyme production was recorded from the 24thh and lasted till the 96thh of incubation when activity peaked to decrease thereafter. Medium optimisation was carried out by Response Surface Methodology (RSM) considering the effects of chitin, corn steep liquor and yeast extract. BM17 chitinolytic activity was induced by chitin but the increase of its concentration did not have significant effects on the enzyme activity. By contrast, the nitrogen source, particularly YE, strongly affected the enzyme production. [Copyright &y& Elsevier]

In this work, a novel laboratory-scale direct steam-injection apparatus (DSIA) was developed to overcome the main drawback of the conventional batch-driven lab rigs, namely the long time needed to heat fiber slurry from room to reaction temperatures greater than 150 °C. The novel apparatus mainly consisted of three units: (i) a mechanically-stirred bioreactor where saturated steam at 5-30 bar can be injected; (ii) an automatic on-off valve to flash suddenly the reaction medium after a prefixed reaction time; (iii) a cyclone separator to recover the reacted slurry. This system was tested using 0.75 dm³ of an aqueous solution of H₂SO₄ (0.5%, v/v) enriched with 50 kg m⁻³ of either commercial particles of Avicel® and Larch xylan or 0.5 mm sieved particles of Tamarix jordanis. Each slurry was heated to about 200 °C by injecting steam at 28 bar for 90 s. The process efficiency was assessed by comparing the dissolution degree of suspended solid (Y(S)), as well as xylose (Y(X)), glucose (Y(G)), and furfural (Y(F)) yields, with those obtained in a conventional steam autoclave at 130 °C for 30 or 60 min. Treatment of T. jordanis particles in DSIA resulted in Y(S) and Y(G) values quite similar to those obtained in the steam autoclave at 130 °C for 60 min, but in a less efficient hemicellulose solubilization. A limited occurrence of pentose degradation products was observed in both equipments, suggesting that hydrolysis predominated over degradation reactions. The susceptibility of the residual solid fractions from DSIA treatment to a conventional 120 h long cellulolytic treatment using an enzyme loading of 5.4 FPU g⁻¹ was markedly higher than that of samples hydrolysed in the steam autoclave, their corresponding glucose yields being equal to 0.94 and 0.22 g per gram of initial cellulose, respectively. Thus, T. jordanis resulted to be a valuable source of sugars for bioethanol production as proved by preliminary tests in the novel lab rig developed here., (Copyright © 2011 Elsevier B.V. All rights reserved.)