Search Results (227)

The increasing demand for sustainable ruminant feeds has driven interest in the valorization of agro-industrial wastes. Artichoke wastes are attractive in the Mediterranean region due to their availability and richness in protein (CP) and fiber (NDF), but their high lignin (ADL) and tannin contents limit their nutritional value. This experiment was conducted using a completely randomized design with four treatments—control, ozone (O₃), exogenous fibrolytic enzyme (EFE), and O₃ + EFE—tested over six runs, each including three replicates per treatment. The study evaluated the effects of ozone (O₃) and exogenous fibrolytic enzyme (EFE) treatments, applied alone or in combination, on artichoke waste chemical composition, ruminal fermentation, microbial populations, enzyme activity, and degradability. Ozone pretreatment significantly reduced fiber fractions (NDF −10%, ADF −7%), ADL (−16%), and condensed tannins (−64%), while increasing CP (+13%) and non-fibrous carbohydrates (NFC +38%). These modifications enhanced ruminal bacterial populations (+29%) and fibrolytic enzyme activities (xylanase +21%, endoglucanase +19%, exoglucanase +10%), resulting in higher dry matter degradability (DMD +11%), fiber degradability (NDFD +14%), total volatile fatty acids (VFAs +13%), and a lower acetate-to-propionate ratio. EFEs alone showed negligible effects; however, when applied after ozone, further improvements were observed in NFCs (+21%), bacterial populations (+21%), enzyme activities (xylanase +11%, endoglucanase +10%), DMD (+8%), NDFD (+7%), and VFAs (+6%) compared to ozone alone. These findings demonstrate that O₃ pretreatment facilitates the enzymatic hydrolysis of lignocellulosic structures and enhances the effectiveness of EFEs, offering a sustainable and eco-efficient strategy for the bioconversion of artichoke wastes into high-value feed for ruminants, contributing to resource efficiency and circular bioeconomy development in livestock systems. Full article

To achieve synchronous regulation of growth and lignocellulose degradation in Pleurotus ostreatus (PO-01) during fungal residue biorefining, we systematically evaluated O₂ gradients (5%, 20%, 40%) and N₂/CO₂ regarding mycelial development, lignocellulose degradation, and bioethanol potential. A total of 20% O₂ emerged as the critical threshold, balancing mycelial growth (which was faster than that under 5% O₂) and lignocellulose degradation (with lignin degradation rate reaching 15.29%). Metabolomics identified 53 aromatic derivatives related to lignin degradation, with their abundance correlating with actual lignin degradation rates. Meanwhile, it clarified the synergistic degradation mechanism and bioinformatics characteristics of key lignin-degrading enzymes and confirmed the AA9 gene associated with cellulose degradation at the molecular level. Measurements of polysaccharide content and ethanol yield revealed that the 20% O₂ environment led to a remarkably high ethanol yield of 101.90 L·ha⁻¹. In contrast, 5% and 40% O₂ concentrations not only reduced the polysaccharide content but also inhibited bioethanol production, highlighting O₂ as a crucial factor in regulating the synergy between growth and degradation. After comprehensive analysis, this study designated 20% O₂ as the optimal parameter for the integrated biorefining of fungal residues, offering a gas-phase solution to overcome industrial bottlenecks in biofuel production. Full article

Ferulic acid esterase (FAE) catalyzes the hydrolysis of the feruloyl ester bond in lignocellulose, exposing cellulose. The objective of this research was to examine the impacts of Bacillus amyloliquefaciens A30 producing FAE on the fermentation quality, fiber degradation, enzyme activity and microbial diversity of corn bran silage and whole-plant corn silage. The experimental treatments were as follows: control (CK), cellulase (CEL), strain A30 (A30) and CEL + A30. Corn bran and whole-plant corn were ensiled for 14 d and 60 d, respectively. The results showed that all additive treatments effectively reduced the pH, neutral detergent fiber, acid detergent fiber and cellulose contents of both corn bran silage and whole-plant corn silage in comparison with control, with CEL + A30 group performing the best effects. Meanwhile, higher FAE activity was detected in A30 and CEL + A30 groups during ensiling. Furthermore, the supplementation of A30 increased the degradation ratio of NDF, ADF, ADL, and cellulose of corn bran silage and whole-plant corn silage. Additionally, treatments with A30 and CEL + A30 increased the abundance of Lactobacillus, and reduced the proportion of pathogenic genera, including Acinetobacter, Enterobacter, and Sphingobacterium. In conclusion, the application of A30 may effectively promote fiber degradation and the stability of microecological system for corn silage. Full article

Straw return is crucial for sustainable agriculture, but its efficiency is limited by low temperatures in cold regions, especially in saline-alkali soils. This study investigates the degradation process of maize straw and the response of soil properties and microbial communities during the winter low-temperature period in the alkaline farmland of Anda, China. A two-year field experiment with straw return (SR) and no return (NR) treatments was conducted. Straw degradation rates and structural changes (as observed via scanning electron microscope, SEM) were monitored. Soil physicochemical properties and enzyme activities were analyzed. Microbial community composition was characterized using 16S rRNA and ITS sequencing. The cumulative straw degradation rate over two years reached 94.81%, with 18.33% occurring in the first winter freeze–thaw period. Freeze–thaw cycles significantly damaged the straw structure, facilitating microbial colonization. Straw return significantly improved soil properties after winter, increasing field water capacity (3.45%), content of large aggregates (6.57%), available nutrients (P 38.17 mg/kg, K 191.93 mg/kg), and organic carbon fractions compared to NR. Microbial analysis revealed that low temperatures filtered the community, enriching cold-tolerant taxa like Pseudogymnoascus, Penicillium, and Pedobacter, which are crucial for lignocellulose decomposition under cold conditions. The winter period plays a significant role in initiating straw degradation in cold regions. Straw return mitigates the adverse effects of winter freezing on soil quality and promotes the development of a cold-adapted microbial consortium, thereby enhancing the sustainability of alkaline farmland ecosystems in Northeast China. Full article

β-glucosidase is a kind of enzyme that can hydrolyze β-glucosidase bonds, and it plays a key role in many fields, such as lignocellulose degradation and wine brewing. The global β-glucosidase market is currently estimated to be USD 40 billion, and more is expected in the future. This trend is mainly due to the demand for enzymes in biofuel processing. At present, β-glucosidase is mainly derived from microorganisms, animals, plants and so on. It has received great attention due to its ease of production, catalytic efficiency and versatility, which have promoted its biotechnology potential in different industries. With the increasing demand for β-glucosidases, various cost-effective methods are being explored to discover, redesign and enhance their production and functional properties. Therefore, this paper reviews the latest progress in the application of β-glucosidase in industry. In this regard, the focus is on the use of recombinant technology, protein engineering and immobilization technology to improve the industrial applicability of the enzyme. In addition, the application status of β-glucosidase in production and life was analyzed. Full article

Thermophilic microorganisms represent an untapped reservoir of thermostable biocatalysts and stress-resilient biomolecules for industrial biotechnology. Aeribacillus pallidus, a Gram-positive moderate thermophile, has attracted attention for its enzymatic versatility and environmental adaptability, yet its genomic potential remains underexplored. Here, we present a comparative genomic analysis of 13 A. pallidus strains to uncover conserved and strain-specific traits relevant to biotechnology. Genomes ranged from 3.24 to 4.98 Mb, with GC content largely conserved (~39%) except for GS3372 (57.4%), indicating possible horizontal gene transfer. All strains encoded complete central metabolic pathways, while carbohydrate-active enzyme profiling revealed abundant glycoside hydrolases and glycosyltransferases, with GS3372 and MHI3390 enriched for lignocellulose-degrading enzymes. Secondary metabolite mining identified diverse biosynthetic gene clusters, including terpenes, sactipeptides, and bacteriocins, with PI8, W-12, and 8m3 exhibiting the greatest biosynthetic diversity. A core set of heat shock and universal stress proteins underscored robust thermotolerance. Phylogenomic and pan-genome analyses revealed high intraspecific diversity and an open pan-genome structure. Collectively, these findings position A. pallidus as a promising thermophilic chassis organism for sustainable applications, including biomass conversion, biofuel production, bioremediation, and the synthesis of heat-stable antimicrobial agents. Full article

Organic manure and grass mulching are widely recognized as modifiers of soil microbial communities and nutrient dynamics; however, the combined effects of these practices on nitrogen fractionation and microbial functionality in orchard ecosystems remain poorly understood. This study conducted a comprehensive evaluation of soil nitrogen fractions, enzymatic activity, microbial diversity and functional traits in walnut orchards under three management practices: organic manure (OM), grass mulching combined with manure (GM), and chemical fertilization (CF) in China’s Loess Plateau. The results revealed that OM and GM significantly enhanced soil nutrient pools, with GM elevating total nitrogen by 1.96-fold, soil organic carbon by 97.79%, ammonium nitrogen by 128%, and nitrate nitrogen by 54.56% relative to CF. Furthermore, the OM significantly increased the contents of total hydrolysable nitrogen, amino sugar nitrogen, amino acid nitrogen, ammonia nitrogen, hydrolysable unidentified nitrogen, non-acid-hydrolyzable nitrogen compared to the CF and GM treatments. Meanwhile, ASN and AN had significant effects on mineral and total nitrogen. The OM and GM had higher activities of leucine aminopeptidase enzymes (LAP), α-glucosidase enzyme, β-glucosidase enzyme (βG), and N-acetyl-β-D-glucosidase enzyme (NAG). Microbial community analysis revealed distinct responses to different treatments: OM and GM enhanced bacterial Shannon index, while suppressing fungal diversity, promoting the relative abundance of copiotrophic bacterial phyla such as Proteobacteria and Chloroflexi. Moreover, GM favored the enrichment of lignocellulose-degrading Ascomycota fungi. Functional annotation indicated that Chemoheterotrophy (43.54%) and Aerobic chemoheterotrophy (42.09%) were the dominant bacterial metabolic pathways. The OM significantly enhanced the abundance of fermentation-related genes. Additionally, fungal communities under the OM and GM showed an increased relative abundance of saprotrophic taxa, and a decrease in the relative abundances of potential animal and plant pathogenic taxa. The Random forest model further confirmed that βG, LAP, and NAG, as well as Basidiomycota, Mortierellomycota, and Ascomycota served as pivotal mediators of soil organic nitrogen fraction. Our findings demonstrated that combined organic amendments and grass mulching can enhance soil N retention capacity, microbial functional redundancy, and ecosystem stability in semi-arid orchards. These insights support the implementation of integrated organic management as a sustainable approach to enhance nutrient cycling and minimize environmental trade-offs in perennial fruit production systems. Full article

Due to its high content of lignocellulose, cotton stalk is difficult to degrade naturally and utilize effectively, so it is often regarded as waste. In this study, the effects of Pleurotus ostreatus XH005, Lactiplantibacillus plantarum LP-2, and cellulase enzyme on the cotton stalk substrate under aerobic solid-state fermentation (SSF) conditions were investigated, and the metabolites were analyzed to identify potential functional compounds in the cotton-stalk-fermented feed. Preliminary optimization results obtained through single-factor experiments were as follows: fermentation time 14 days, XH005 inoculum size 8.00% (v/m), material-to-water ratio 1:0.50 (v/m), LP-2 inoculum size 2.00% (v/m), and cellulase addition 0.60% (m/m). Based on these single-factor experimental results, XH005 inoculum size, LP-2 inoculum size, material-to-water ratio, and cellulase addition were selected as independent variables. Through response surface methodology (RSM) optimization experiments, 29 experimental groups were designed. Subsequently, based on Box–Behnken analysis of variance (ANOVA) of lignin and cellulose content, along with contour and response surface plots, the optimal aerobic solid-state fermentation parameters were determined as follows: fermentation time 14 days, XH005 inoculum: 7.00% (v/m), material-to-water ratio: 1:0.55 (v/m), LP-2 inoculum: 2.00% (v/m), and cellulase enzyme addition: 0.65% (m/m). Results showed that compared with the control group (CK), the optimized group exhibited a 27.65% increase in lignin degradation rate and a 47.14% increase in cellulose degradation rate. Crude protein (CP) content increased significantly, while crude fiber (CF), detergent fiber and mycotoxin contents decreased significantly. Non-targeted metabolic analysis indicated that adding cellulase and inoculating Pleurotus ostreatus XH005 and Lactiplantibacillus plantarum LP-2 in aerobic SSF of cotton straw feed produced functionally active substances such as kaempferol (C343), carvone (C709) and trilobatin (C604). Therefore, this study demonstrates that microbial-enzyme co-action SSF significantly enhances the nutritional composition of cotton stalk hydrolysate. Furthermore, this hydrolysate is suitable for the production of functional compounds, endowing the fermented feed with health-promoting properties and enhancing the utilization of cotton processing byproducts in the feed industry. Full article

The efficient degradation of lignin from agricultural by-products is a critical step in the development of sustainable bioprocessing technologies for waste valorisation. Enzymatic degradation of kraft lignin performed with lignin peroxidase (LiP), manganese peroxidase (MnP), and laccase (Lac) was investigated. A response surface methodology (RSM) based on a Box–Behnken Design (BBD) was employed in order to optimise key process parameters including enzyme concentration, lignin concentration, pH, incubation temperature, and activator concentration. The surface plots were used to determine the best conditions for each enzyme in order to better degrade kraft lignin. Therefore, LiP needed a stronger acidic environment and moderate temperature, MnP needed an almost neutral pH and moderate temperature, and Lac needed a neutral pH and higher temperature. This work contributes to the development of smart agricultural waste management practices by combining enzymatic treatments with statistical modelling for process optimisation. This study provides a framework for lignin degradation that can be used as a starting point for diverse lignocellulosic by-product fragmentation, thus supporting a circular bioeconomy initiative in accordance with today’s trends. The optimised enzymatic parameters could help enhance efficiency, enable process standardisation across feedstocks, and support economically and environmentally sustainable industrial-scale lignin valorisation in integrated biorefineries. Full article

This study reports the isolation and optimization of cellulase-producing bacteria from the gastrointestinal tract of South African goats for the pretreatment of lignocellulosic biomass in bioenergy applications. Among the isolates, three strains, Bacillus KC50, Bacillus KC70, and Proteus mirabilis KC94, were identified by 16S rDNA sequencing. To our knowledge, this is the first report of cellulolytic optimization in P. mirabilis derived from goat rumen. Enzyme production was optimized under varying pH, temperature, and incubation conditions. P. mirabilis KC94 exhibited robust enzyme activity at pH 7 and 35 °C, with stability across a broader range than the Bacillus strains. Peak activity occurred at 84 h of incubation, reflecting strain-specific metabolic adaptation. The presence of organic solvents and surfactants inhibited enzyme activity, whereas mild oxidative stress induced by H₂O₂ stimulated cellulase production. Amplification of GH39, GH45, and GH48 genes revealed KC94’s strong genetic potential for efficient lignocellulose degradation. These findings highlight the biotechnological potential of rumen-derived cellulolytic bacteria, particularly P. mirabilis KC94, for advancing sustainable bioenergy systems. Full article

Thefilamentous fungus Trichoderma reesei is renowned for its exceptional ability to secrete cellulolytic enzymes, which play a crucial role in the hydrolysis of lignocellulose biomass. The expression of fungal cellulases is meticulously regulated at the transcriptional level, depending on the carbon source available in the medium. To obtain new insights into the transcriptional network controlling cellulase expression in T. reesei, we analyzed RNA-Seq data and identified and characterized a new transcription factor, Rme1, that regulates the expression of cellulolytic genes. Combining functional genomics and protein-DNA interaction assay, we showed that Rme1 acts as a repressor of cellulase production in T. reesei by directly regulating two critical genes involved in cellulose degradation: the cellobiohydrolase cel7a and the carbon catabolite repressor cre1. This is the first report of a transcription factor regulating Cre1. This study contributes to a better understanding of the complex regulation of the cellulolytic system of T. reesei and may be useful for the genetic modification of strains for the biorefinery industry. Full article

Colletotrichum graminicola, the causative agent of maize anthracnose leaf blight and stalk rot, severely jeopardizes the healthy development of the maize industry. Auxiliary activity enzymes (AAs), a vital subclass of carbohydrate-active enzymes, act as beneficial accessory proteins for fungi in degrading lignocellulose. This study identified 127 AA genes from the genome of C. graminicola strain TZ-3 and further analyzed the subcellular localization, conserved motifs, and domains of the proteins encoded by these genes. The CgAA genes exhibited significant variations in gene structure, and the structural motifs within their encoded proteins also differed. Subcellular localization analysis revealed that most CgAA proteins were localized in the extracellular space. Moreover, the CgAA gene family contained abundant conserved domains, suggesting diverse functionalities and potential roles in various fungal biological processes. Multiple cis-acting regulatory elements related to stress responses and plant hormones were detected in the promoter regions of these genes. This study analyzed the expression patterns of CgAA genes during pathogen–host interactions and found that most CgAA genes were differentially expressed in the interaction between C. graminicola and maize. Coupled with GO functional analysis, it was discovered that CgAAs are deeply involved in the interaction between C. graminicola and maize, closely associated with the pathogenic mechanisms of the pathogen, and may play crucial roles in the initiation and expansion of fungal infections. These results provide valuable resources for elucidating the functions of AA genes and lay the groundwork for sustainable agricultural development through the utilization of AA genes in disease control and the breeding of stress-resistant, high-yield crop varieties. Full article

Talaromyces pinophilus is a filamentous fungus with notable lignocellulose-degrading capacity based on enzyme activities and protein secretion potential, making it a compelling candidate for industrial biotechnology applications. In this study, we present the genomic characterization of the highly cellulolytic strain Y117, a domesticated variant of T. pinophilus, based on whole-genome sequencing and comparative genomic analysis with eleven related strains. Comprehensive analysis of CAZymes, transcription factors, and secondary metabolite diversity in T. pinophilus strains revealed that the exceptional lignocellulose degradation capacity of Y117 is driven by its unique genomic architecture. Key genomic features that distinguish Y117 include (1) significant expansion of glycoside hydrolase (GH) and carbohydrate-binding module (CBM) families, (2) loss of fungal-RiPP-like clusters, and (3) absence of the developmental regulator BrlA. These genomic adaptations could indicate a metabolic trade-off favoring hydrolytic enzyme production over secondary metabolism and sporulation. Our findings provide fundamental insights into fungal lignocellulose degradation mechanisms while establishing Y117 as a promising chassis for metabolic engineering applications in industrial enzyme production and heterologous protein expression. Full article

Flammulina filiformis, one of the most delicious and commercially important mushrooms, demonstrates remarkable adaptability to diverse agricultural wastes. However, it is unclear how different substrates affect the degradation of lignocellulosic biomass and the production of lignocellulolytic enzymes in F. filiformis. In this study, label-free comparative proteomic analysis of F. filiformis cultivated on sugarcane bagasse, cotton seed shells, corn cobs, and glucose substrates was conducted to identify degradation mechanism across various substrates. Label-free quantitative proteomics identified 1104 proteins. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway analysis of protein expression differences were predominantly enriched in energy metabolism and carbohydrate metabolic pathways. Detailed characterization of carbohydrate-active enzymes among the identified proteins revealed glucanase (GH7, A0A067NSK0) as the key enzyme. F. filiformis secreted higher levels of cellulases and hemicellulases on sugarcane bagasse substrate. In the cotton seed shells substrate, multiple cellulases functioned collaboratively, while in the corn cobs substrate, glucanase predominated among the cellulases. These findings reveal the enzymatic strategies and metabolic flexibility of F. filiformis in lignocellulose utilization, providing novel insights for metabolic engineering applications in biotechnology. The study establishes a theoretical foundation for optimizing biomass conversion and developing innovative substrates using targeted enzyme systems. Full article

Ferulic acid (FA) is one of the most abundant hydroxycinnamic acids found in plant cell walls. Its dehydrodimers play an important role in maintaining the structural rigidity of the plant cell wall. Ferulic acid esterases (FAEs) act as debranching enzymes, cleaving the ester bond between FA and the substituted carbohydrate moieties in FA-containing polysaccharides in the plant cell wall. This enzymatic reaction facilitates the degradation of lignocellulosic materials and is crucial for the efficient utilization of biomass resources. This review focuses on the occurrence of ferulic acid in nature and its different forms and outlines the various classification systems of FAEs, their substrate specificity, and the synergistic interactions of these enzymes with other CAZymes. Additionally, it highlights the various methods that have been developed for detecting hydroxycinnamic acids and estimating the enzyme activity, as well as the versatile applications of ferulic acid. Full article