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The potent utilization of hemicellulosic fraction, which comprises one-third of carbohydrates in lignocellulosic biomass (LCB), is vital to strengthen the bioethanol production from it. Most studies on bioethanol production from LCB focused on cellulosic fraction only, or very low ethanol productivity is reported from hemicellulosic fraction. The present study investigated a process to convert the hemicellulosic fraction of wheat straw biomass to bioethanol effectively using Scheffersomyces stipitis. This work aimed to develop and demonstrate a systematic approach for scaling up the fermentation process, keeping the volumetric oxygen transfer coefficient (k L a) nearly constant in different scale bioreactors. It was found that 99.11±0.13% of synthetic xylose and 99.04±0.10% of lignocellulosic xylose were converted to bioethanol with a yield and productivity of 0.4706±0.0022 g/g and 1.5325±0.0020 g/Lh; 0.4290±0.0030 g/g and 0.7399±0.0043 g/Lh, respectively at an optimum k L a of 0.5776 (0.5735, 0.5817) min−1 and 0.6924 (0.6887, 0.6961) min−1, respectively in a 0.5 L bioreactor. After that, these optimum k L a were validated in 1 L and 5 L bioreactors. The successful k L a validation revealed that the hemicellulosic fraction of lignocellulosic biomass could also be well utilized for bioethanol production. • Potent utilization of hemicellulosic fraction of LCB to produce bioethanol. • Optimum k L a for S. stipitis to produce bioethanol from xylose in 0.5 L bioreactor. • Fermentation scale-up to 1 L and 5 L bioreactors based on k L a. • Application of k L a studies on fermentation of hemicellulosic fraction of LCB. • 1.53 and 0.74 g/Lh ethanol productivity from synthetic and lignocellulosic xylose. [ABSTRACT FROM AUTHOR]

Environmental factors significantly affected the succession of microbial communities during the fermentation of Huangjiu Raw wheat Qu (RWQ). Influence of environmental factors on microbial community during fermentation of Chinese Huangjiu RWQ. The interaction of environmental factors and microorganisms affects the changes of microbial communities and key enzyme transcript levels in different stages during the production of Huangjiu RWQ. This study combined environmental factor analysis and high-throughput sequencing technology to comprehensively analyze the specific changes of microbial communities and environmental factors at each stage of Huangjiu production. In addition, the influence of the interaction of environmental factors and microorganisms on microbial succession was investigated by correlation analysis, and the enzymes related to saccharification and ethanol fermentation during the production of RWQ were explored. The results showed that Bacillus , Weisseria , Thermophilic actinomycetes and Lactobacillus were the dominant bacteria in RWQ, while Aspergillus , Thermomyces , Fusarium and Alternaria were the dominant fungi. Fungi were active in the early stage of RWQ fermentation, while bacteria were active in the middle and late stage of fermentation. Microbial community succession was closely related to environmental humidity and CO 2. These environmental factors were positively correlated with most fungi, but negatively correlated with Thermophilic actinomycetes, Glycopolyspora and Acinetobacter. In fungi, the enzymes related to saccharification and fermentation mainly came from Thermophilic ascomycetes and thermophilic fungi , while in Bacteria , these two enzymes mainly came from weisseria. This study revealed the relationship between RWQ microbe and environmental factors, which was helpful to clarify the succession law of RWQ microbe. [Display omitted] • Revealed the relationship between microbe in wheat Qu and environmental factors. • Influence of interaction between environment and microorganisms on microbial succession. • Clarified the succession rule of microbe in wheat Qu. [ABSTRACT FROM AUTHOR]

• Microbial consortium designed using five robust lignocellulolytic bacteria. • Kinetic study reveals enzyme cocktail's strong affinity for wheat straw as substrate. • Consortium-mediated enzyme cocktails showed 89% wheat straw saccharification. • Genomic analysis of strains reveals unique GHs and LPMOs contributing to synergy. • Designed consortia offer a sustainable approach for lignocellulose bioconversion. The potential of hydrolytic enzyme cocktail obtained from designed bacterial consortium WSh-1 comprising Bacillus subtilis CRN 16, Paenibacillus dendritiformis CRN 18, Niallia circulans CRN 24, Serratia marscens CRN 29, and Streptomyces sp. CRN 30, was investigated for maximum saccharification. Activity was further enhanced to 1.01 U/ml from 0.82 U/ml by supplementing growth medium with biotin and cellobiose as a cofactor and inducer. Through kinetic analysis, the enzyme cocktail showed a high wheat straw affinity with Michaelis-Menten constant (Km) of 0.68 µmol/L and a deconstruction rate (Vmax) of 4.5 U/ml/min. The statistical optimization of critical parameters increased saccharification to 89 %. The optimized process in a 5-L lab-scale bioreactor yielded 501 mg/g of reducing sugar from NaOH-pretreated wheat straw. Lastly, genomic insights revealed unique abundant oligosaccharide deconstruction enzymes with the most diverse CAZyme profile. The consortium-mediated enzyme cocktails offer broader versatility with efficiency for the economical and sustainable valorization of lignocellulosic waste. [ABSTRACT FROM AUTHOR]

[Display omitted] • Fraction separation of wheat straw with AFEX-assisted DES pretreatment. • DES with reduced pH and viscosity enhances lignin removal. • AFEX-assisted DES pretreatment increases cellulose accessibility in wheat straw. • The enzymatic efficiency of the one-pot pretreatment of wheat straw was 97.96%. • Enzyme efficiency remained greater than 85 % for three pretreatment cycles. In this study, an ammonia fiber expansion (AFEX)-assisted deep eutectic solvent (DES) pretreatment method was developed for the rapid separation of wheat straw fractions, which reduced the pretreatment time for DES and improved the pretreatment efficiency. This study describes the feasibility of the AFEX-assisted DES pretreatment in terms of both progressive and parallel relationships and analyzes the subsequent enzymatic effect in generating glucose from cellulose. Ammonia fiber expansion-assisted DES one-pot pretreatment at 120 °C, for 1.5 h resulted in an enzymatic efficiency of 98.0 ± 3.1 %. Moreover, the enzyme efficiency remained greater than 85 % after three recovery cycle experiments. The comparison between regenerated-lignin (d -lignin) and alkaline-lignin showed that regenerated lignin has a lower molecular weight and belongs to para -hydroxy-phenyl-guaiacyl-syringyl (H-G-S) type lignin. This study developed is a green and efficient pretreatment process with great potential in the separation and utilization of biomass fractions. [ABSTRACT FROM AUTHOR]

[Display omitted] • Bioconversion of lignocellulosic waste and cattle manure to energy was investigated. • Batch-mode mesophilic bioreactors were used in anaerobic co-digestion process. • Two TS levels of 3 and 6% at three ISRs of 1, 2, and 4 were evaluated. • The best performance of 0.510 m3-biogas/kg-VS added was observed at TS = 3 and ISR = 1. • The lower the ISR, the higher biogas and methane yield. • The MG and LF kinetic models offered the highest consistency with experimental data. Rising concerns about environmental issues including pollution control, waste management and energy demands have drawn the world's attention to the merits of renewable energy sources. In this regard, the anaerobic digestion of organic wastes for the purpose of bioenergy production is of particular importance. This study investigated the potential for biogas production from the co-digestion of a lignocellulosic biomass (wheat straw) with cattle manure after physical and chemical pretreatment at two Total Solids (TS) levels of 3% and 6% and three Inoculum-to-Substrate Ratios (ISRs) of 1, 2 and 4 (based on volatile solids). The materials were loaded into single-stage 1-liter digesters in batch mode under mesophilic conditions (35 °C) for 125 days. The best anaerobic digestion performance was observed in the treatment with 3%TS and ISR1, where the biogas and methane production yields were 0.510 and 0.307 m3/kg-VS added , respectively. At both TS levels, biogas production increased with the increase in the Volatile Solids (VS) content of wheat straw and the decrease in ISR. This can be due to easier access of microorganisms to the organic matter and better microorganism-substrate balance, which ultimately result in improved digestion performance. The kinetic modeling results showed that the modified Gompertz model and the logistic function model had the highest level of consistency with the experimental results for TS3% and TS6%, respectively. The first-order kinetic model failed to provide a good estimate of biogas production from the co-digestion of wheat straw with cattle manure, irrespective of the TS level. [ABSTRACT FROM AUTHOR]

[Display omitted] • Enantioselective fate of pydiflumetofen (PYD) was observed in wheat. • R -PYD was more easily accumulating in wheat roots and translocating to shoots. • A total of 9 metabolites of PYD were detected in wheat roots and shoots. • PYD was uptake via symplastic pathway, dominated by aquaporin and anion channels. • Ta LTP 1.1 and CYP71C6v1 revealed the enantioselective fate of PYD in wheat. Pydiflumetofen (PYD), a highly effective and broad-spectrum fungicide, is commonly employed for the control of fungal diseases. In this study, the uptake, translocation, and biotransformation of PYD by wheat (Triticum aestivum L.) were firstly investigated at a chiral level. The findings revealed that the residue concentration of R -PYD in wheat was higher than that of S -PYD, because of its higher uptake rate (k 1 = 0.0421 h−1) and lower elimination rate (k2 = 0.0459 h−1). Additionally, R -PYD exhibited higher root bioconcentration factors and translocation factors compared with S- enantiomer, indicating R -PYD was more easily accumulating in roots and translocating to shoots. Furthermore, a total of 9 metabolites, including hydroxylated, demethylated, demethoxylated, dechlorinated, hydrolyzed, and glycosylated-conjugated products, were detected qualitatively in wheat roots or shoots. Symplastic pathway-mediated uptake, which predominantly relied on aquaporins and anion channels, was confirmed by root adsorption and inhibition experiments, without displaying any enantioselective effect. Molecular simulations demonstrated that R -PYD exhibited stronger binding affinity with Ta LTP 1.1 with a lower grid score (−6.79 kcal/mol), whereas weaker interaction with the metabolic enzyme (CYP71C6v1) compared to the S- enantiomer. These findings highlight the significance of plant biomacromolecules in the enantioselective bioaccumulation and biotransformation processes. Importantly, a combination of experimental and theoretical evidence provide a comprehensive understanding of the fate of chiral pesticides in plants from an enantioselective perspective. [ABSTRACT FROM AUTHOR]

Wheat straw was hydrothermally pretreated over a broad severity range (90–300 °C) to comparatively assess its suitability for energy application scenarios. Although the substrate was not completely deconstructed at the rather low temperature of 120 °C, the biomethane yield through whole slurry anaerobic digestion was 32% higher than that of unpretreated wheat straw. It was proposed that an increasing amount of soluble fractions was released at higher pretreatment temperatures, which consequently limited anaerobic digestion through the acidification or inhibition mechanism; therefore a lower biomethane yield was obtained. In contrast to the profile of anaerobic digestion, increasing the pretreatment temperature significantly facilitated bioethanol production through simultaneous saccharification and fermentation (SSF). When the hydrothermal pretreatment was performed at 210 °C, the ethanol yield was 229.5% higher than that of the untreated wheat straw. The possible reason was that at higher temperatures, the recalcitrant fraction of hemicellulose tended to solubilize through auto acid-catalyzed hydrolysis, which enhanced the accessibility of cellulose to cellulase enzymes. At very high hydrothermal temperatures (≥240 °C), the pretreated substrates were not suitable for biological conversion but were well suited for production of carbons with an ultra-high surface area. In conclusion, lower pretreatment temperatures are recommended for anaerobic digestion, moderate temperatures for SSF, and high temperatures for non-biological conversion to produce supercapacitor carbon electrodes. [Display omitted] • Hydrothermally pretreated wheat straw for bioconversion in whole slurry. • The maximum methane yield of 145.8 mL/g TS was obtained at 120 °C. • The derived soluble fractions were crucial to anaerobic digestion. • Better ethanol yield of 5.6 g/L achieved at 210 °C for the proper deconstruction. • Extra high temperatures were suggested for carbon electrode for energy storage. [ABSTRACT FROM AUTHOR]

[Display omitted] • Bacillus strains were able to grow and degrade wheat bran releasing soluble sugars. • Members of bacterial consortia were selected based on cluster analysis. • Consortium of bacterial strains increased significantly cellulolytic activities. • Efficacy of the consortium in wheat bran pretreatment was increased significantly. • Bacillus consortia showed an increase in cellulose bioconversion than pure cells. In the downstream process, the bioconversion of lignocellulosic biomass can be improved by applying a biological pretreatment procedure using microorganisms to produce hydrolytic enzymes to modify the recalcitrant structure of lignocellulose. In this study, various Bacillus strains (B. subtilis B.01162 and B.01212, B. coagulans B.01123 and B.01139, B. cereus B.00076 and B.01718, B. licheniformis B.01223 and B.01231) were evaluated for the degrading capacity of wheat bran in the submerged medium using enzymatic activities, reducing sugars and weight loss as indicators. The obtained results revealed that the B. subtilis B.01162, B. coagulans B.01123 and B. cereus B.00076 could be promising degraders for the wheat bran pretreatment. Besides, the application of their consortium (the combination of 2–3 Bacillus species) showed the positive effects on cellulose bioconversion compared with monocultures. Among them, the mixture of B. subtilis B.01162 and B. coagulans B.01123 increased significantly the cellulase, endo -glucanase, and xylanase enzyme activity resulting in accelerating the lignocellulose degradation. Our results served a very good base for the development of microbial consortium for biological pretreatment of lignocellulosic raw materials. [ABSTRACT FROM AUTHOR]

[Display omitted] • Rumen microorganisms rapidly and efficiently hydrolyzed and acidified corn straw. • Rumen bacterial and fungal community composition significantly changed in 72 h. • Low pH and VFA accumulation were the main factors affecting bacteria and fungi. • Bacterial networks were more complex than that of fungal networks. • CAZymes family and genes expression significantly decreased after 72 h fermentation. Anaerobic fermentation of corn straw with rumen microorganisms as inoculum to produce volatile fatty acids (VFAs) is important for biomass valorization. In this study, dynamic variation in bacterial and fungal community composition, carbohydrate-active enzymes (CAZymes) and key functional genes related with VFA production was explored via metagenomic sequencing. Rumen microorganisms efficiently hydrolyzed and acidified corn straw, and VFA concentration reached 8.99 g/L in 72 h. Bacterial and fungal community significantly changed, but the core genera kept stable. Low pH and VFA accumulation were the main factors affecting bacterial and fungal communities. The positive correlations between bacteria were more complex than those between fungi. Most CAZyme abundance significantly decreased after 72 h fermentation, and functional gene abundance participating in VFA generation also decreased. This study provided new insights into dynamic variation of bacteria and fungi during anaerobic ruminal fermentation in vitro, promoting the application of rumen microorganisms in practice. [ABSTRACT FROM AUTHOR]

• Black Soldier Fly larvae convert biosolids into protein- and fat-rich biomass. • Efficient reduction of biosolids substrates of < 40% within 20 days. • Heavy metals from biosolids get partitioned into residues but not mature larvae. • Heavy metals in larvae that fed on biosolids blends is below limits for animal fodder. • Substrate bioconversion is affected by volatile solids content, Mg, Mn, pH, and Ca. Annually, over 30 million dry tonnes of biosolids are produced worldwide, most of which are disposed into landfills or discharged into waterbodies, exacerbating eutrophication and water-borne diseases. Bioconversion of biosolids using Black Soldier Fly larvae (BSFL) can produce high-value biomass (protein, lipids, and chitin) while reducing the volume of waste that requires disposal. We aimed to determine the bioconversion performance of BSFL on different types of biosolids and biosolids blends and analysed the bioaccumulation of heavy metals in the larvae. BSFL converted all substrates into larvae biomass of similar protein content (31–37%). However, larvae growth and substrate reduction were significantly lower for unblended biosolids compared to wheat bran. Blending of biosolids with other organic waste such as food waste or wheat bran improved larvae performance (< 40% substrate reduction after 20 days; < 149 kg larvae/ tonne dry substrate) and fat content (< 31%). Despite initial high concentrations in biosolids (< 8700 mg/ kg), heavy metals were largely partitioned into the residues instead of the mature BSFL, resulting in low bioaccumulation of those elements in BSFL (< 180 mg/ kg). These concentrations were even below limits of international guidelines for animal feed. Therefore, this study demonstrated that BSF-based bioconversion can be an innovative and sustainable waste management and resource recovery technology to rapidly reduce the volumes of biosolids while transforming it into high-value biomass of low heavy metal concentrations. [Display omitted] [ABSTRACT FROM AUTHOR]

Waste generated during aquaculture can be converted into bioflocs. Black soldier fly larvae (BSFL) are a valuable resource for the treatment of organic waste. This study evaluated the effect of feeding BSFL with bioflocs for the first time with the aim of providing a new approach for the resource utilization of aquaculture solid waste. Six treatment groups were established by feeding BSFL with fermented bioflocs (A1), bioflocs (B1), fermented wheat bran (A2), wheat bran (B2), fermented mixed diet (A3), and mixed diet (B3). The survival rates (SR) of the six treatment groups were not significantly different. The crude protein and lipid contents of the final BSFL were 50.9–63.94% and 3.96–7.73%, respectively, in the six treatment groups. The BSFL of B2 had the highest crude protein and lowest crude ash content while those of B1 had the lowest crude protein content and highest crude ash content. Oleic and linoleic acids were the predominant fatty acids in BSFL for all groups (>53.25%) and B3 BSFL contained three essential fatty acids (EFAs). By analyzing the effect of BSFL culture and biofloc reduction, we determined that bioflocs and wheat bran mixed at a ratio of 6:4 (dry matter) is ideal for cultivating BSFL. Overall we found that BSFL can directly treat bioflocs and the bioflocs intend provide ideal nutrients for BSFL, which implies a potential method for cleaner production in aquaculture. • Black soldier fly larvae (BSFL) can directly feed on bioflocs and treat bioflocs. • Biofloc and wheat bran mix at a ratio of 6:4 (dry matter) can achieve the best results. • No difference in treated efficiency of fermented and unfermented mixed substrate. • Crude protein and crude fat of BSFL feed on mixed subatrate were 53.58% and 3.96%. • BSFL feed on mixed substrate contain four types fish EFA. [ABSTRACT FROM AUTHOR]

[Display omitted] • Two novel xylanase genes from T. asperellum were expressed for the first time. • XynTR10 and XynTR11 displayed high halophilic and ethanol tolerant. • XynTR11 hydrolyzed xylan/XOS into xylobiose without xylose via transglycosylation. • Glu153/Glu258 and Glu161/Glu252 were the key active sites for XynTR10 and XynTR11. • XynTR11 holds great potential for XOS production from agricultural waste. Effective production of xylooligosaccharides (XOS) with lower proportion of xylose entails unique and robust xylanases. In this study, two novel xylanases from Trichoderma asperellum ND-1 belonging to glycoside hydrolase families 10 (XynTR10) and 11 (XynTR11) were over-expressed in Komagataella phaffii X-33 and characterized to be robust enzymes with high halotolerance and ethanol tolerant. Both enzymes displayed strict substrate specificity towards beechwood xylan and wheat arabinoxylan. (Glu153/Glu258) and (Glu161/Glu252) were key catalytic sites for XynTR10 and XynTR11. Notably, XynTR11 could rapidly degrade xylan/XOS into xylobiose without xylose via transglycosylation. Direct degradation of corncob using XynTR10 and XynTR111 displayed that while XynTR10 yielded 77% xylobiose and 25% xylose, XynTR11 yielded much less xylose (11%) and comparable amounts of xylobiose (63%). XynTR10 or XynTR111 has great potential as a catalyst for bioconversion of xylan-containing agricultural waste into high-value products (biofuel or XOS), which is of significant benefit for the economy and environment. [ABSTRACT FROM AUTHOR]

The increasing global demand for sustainable and eco-friendly alternatives has led to a growing interest in the valorization of lignocellulosic biomass for the production of high-value compounds. Thus, feedstock sustainability and environmental load reduction necessitate processing and value-added reuse methods. Because of its many usable components, biomass can be valorized in many ways, benefiting the economy and environment. This biomass can manufacture bulk and specialized chemicals cheaply and slowly. They may also be used to create a variety of natural flavors through microbial transformation. One of the most crucial flavoring ingredients in the food sector is vanillin. In recent years, there has been a significant increase in research into the biotechnological synthesis of ferulic acid from byproducts and wastes of the agro-food sector. Ferulic acid has been extensively extracted from maize, rice, wheat, and other lignocellulosic biomass. Crude hydrolysates from the plant source and refined ferulic acid have been used to make "natural" vanillin biologically. Vanillin made from lignocellulosic biomass may provide this flavor in a unique, cost-effective, and environmentally beneficial way. This review examines the latest enzymatic, microbiological methods, and bioconversion technologies for bio vanillin synthesis from lignocellulosic biomass. It highlights the wide range of agro-waste sources such as lignocellulosic materials, agricultural byproducts, and food processing wastes. This review addresses the valorization of lignocellulosic biomass, sustainability, and the demand for natural alternatives to encourage bio vanillin production from residues. • An in-depth review on the valorization of agro-waste products. • Attempt to focus on the production of vanillin from byproducts of the agro-industry. • Lignocellulosic waste increased vanillin yield considerably. • Vanillin production, relies on microbial diversity and biotransformation. • Vanillin production from agro waste has the potential to provide a sustainable and cost-effective alternative to traditional methods of vanillin extraction. [ABSTRACT FROM AUTHOR]

To achieve a waste-free clean production, the present study aimed to valorize an underused agroindustrial byproduct (rice bran) by mealworms bioconversion and produce bio-oil from pyrolysis of insect excreta (frass) as bioinsecticide. To reach the first goal, the suitability of rice bran (RB) versus standard diet, wheat bran (WB), was examined by determining feed conversion, growth performance, and nutritional profile of T. molitor larvae. RB diet was an appropriate feed substrate for breeding mealworms, as evidenced by their high survival rates, optimal feed conversion parameters, and its capability to support the growth and life cycle of this insect. Besides, RB did not affect soluble larval protein content but modified crude fat content and fatty acid profile. In order to address the second aim, egested frass from RB and WB were subjected to pyrolysis to obtain bio-oils. The main compound was acetic acid (≈37%) followed by 1,6-anhydro-β-d-glucopyranose (from 16 to 25%), as measured by GC-MS analysis. Nitrogen-containing chemicals accounted for ≈10%. Frass bio-oils could represent a novel source of bioinsecticides due to their bioeffectiveness in insect pests of economic importance (Plodia interpunctella and Tribolium castaneum) and medical interest (Culex pipiens pipiens). For P. interpunctella adults, frass bio-oils produced insecticidal activity by fumigant and contact exposure whereas for T. castaneum adults, just fumigant. By a miniaturized model that simulates semireal storage conditions, it was seen that, on T. castaneum , frass RB bio-oil generated higher repellent effect than frass WB. Finally, bio-oils proved to have larvicidal activity against Cx. p. pipiens. [Display omitted] • This work investigates mealworm bioconversion coupled to bioinsecticide production. • RB as suitable feed substrate for T. molitor development. • This is first report on the insecticidal activity of bio-oils from frass pyrolysis. • Frass bio-oils induce lethal effects on insect of economic and medical interest. • Simulating semireal storage conditions, frass bio-oils produce repellent effect. [ABSTRACT FROM AUTHOR]

Nongxiangxing daqu (daqu), which is produced by the open fermentation of wheat, is the fermentation starter of baijiu. This work reports the occurrence and driving factors of microbial community succession (MCS), which determines daqu quality, during daqu fermentation. The co-occurrence networks of the 2 stages of the MCS showed that module 2 of stage P1 contained Mucoromycota and Actinobacteriota and was affected by temperature, humidity, CO 2 , and moisture; module 8 of stage P2 contained Mucoromycota and Saccharomycetes and was influenced by acidity and moisture. Twenty-two genera were thebiomarkers of the MCS. The MCS was driven by temperature, humidity, CO 2 , O 2 , acidity,moisture and interactions between the biomarkes and Lactobacillales, Saccharomycetales, and Acetobacter. The main driving factors of the bacterial community succession were acidity, moisture, and temperature, and that of the fungal community succession was moisture. These results guide the control of MCS during daqu fermentation. [ABSTRACT FROM AUTHOR]

Taurocholic acid (TCA) is abundant in the rat intestine and has multiple health benefits. In the gut, intestinal microbiota can transform TCA into different bile acid (BA) derivatives, with the composition of microbiota playing a crucial role in the transformation process. This study aims to investigate how lotus seed resistant starch (LRS) can regulate microbiota to influence BA transformation. A fecal fermentation study was conducted in vitro, using either LRS, high-amylose maize starch (HAMS), or glucose (GLU) to analyze microbiota composition, BA content, and metabolic enzyme activities over different fermentation times. Bioinformatics analysis found that LRS increased the relative abundance of Enterococcus , Bacillus , and Lactobacillus , and decreased Escherichia-Shigella , compared with HAMS and GLU. LRS also reduced total BA content and accelerated the conversion of TCA to cholic acid, deoxycholic acid, and other derivatives. These results reveal that LRS and GLU tend to mediate the dehydroxy pathway, whereas HAMS tends to secrete metabolic enzymes in the epimerization pathway. Therefore, the evidence that LRS may regulate TCA bioconversion may benefit human colon health research and provide an important theoretical basis, as well as offer new concepts for the development of functional foods. [ABSTRACT FROM AUTHOR]

The open culture system exhibits several advantages in bioconversion of complex substrates into caproate, yet it is urgent to develop an advanced approach to overcome the low fermentative efficiency. In this study, three reinforcement techniques were employed to reinforce the chain elongation in the open culture system, including bioaugmentation, pretreatment of anaerobic sludge (AS) and addition of cell carrier. Results showed that the caproate production was improved to 48.9 mmol/L using bioaugmentation technology. With removal of methanogen by alkaline-thermal pretreatment, the caproate production increased to 94.8 mmol/L. The highest caproate production of 130.5 mmol/L was obtained with addition of cell carrier, which was explained by the formation of biofilm. The genus Clostridium_sensu_stricto capable of medium chain fatty acids production dominated the microbiome of the AS. This study provides an insight that efficient caproate production can be achieved in the open culture system by reinforcing the pathway of chain elongation. [Display omitted] • Caproate production was improved in the open culture system. • Acetate competition was reduced via eliminating acetoclastic methanogen. • The biofilm on the cell carrier reinforced the pathway of chain elongation. • The genus Clostridium_sensu_stricto dominated the microbiome of anaerobic sludge. [ABSTRACT FROM AUTHOR]

[Display omitted] • Comparative genome wide sequence analysis of Aspergillus strains. • Developing hyper lignocellulolytic strain of A. allahabadii. • Secretome profiling identifies up-regulated GH and transcriptional factor in mutant. • Enzyme cocktail of mutant MAN 40 and CBH from R. emersonii for efficient hydrolysis. • In situ addition of cellulase for valorization of waste lignin stream in biogas. The study was aimed at developing lignocellulolytic strain capable of efficient hydrolysis of mild alkali deacetylated (MAD) rice straw. The valorisation of lignin rich black liquor obtained during pre-treatment of rice straw into biogas was also evaluated. Study reports highly proficient cellulolytic Aspergillus allahabadii strain harbouring a spectrum of CAZymes based on comparative genome wide analysis that was subjected to strain breeding for developing a hyper producing strain. The secretome analysis showed up-modulation and several folds increase in the CAZyme activities in the culture extracts of the developed strain MAN 40 when compared to parent. The cellulolytic cocktail of the developed strain showed 1.52 folds higher saccharification of MAD rice straw when compared to Cellic CTec 3. Moreover, in-situ addition of cellulases derived from developed strains resulted in ∼3.7 folds higher methane production during anaerobic digestion of mixture of lignin rich black liquor and differently treated rice straw. [ABSTRACT FROM AUTHOR]