Search Results (586)

Oilseed meal, the primary by-product of oil extraction, is rich in protein, dietary fiber, and minerals, offering significant development potential. However, its application in high-value feed and food is severely restricted due to anti-nutritional factors, leading to resource waste and environmental issues. Solid-state fermentation (SSF) provides a green and efficient approach for the high-value utilization of oilseed meal. This review comprehensively discusses the entire process of strain selection, fermentation strategies, and application of active products in the SSF of oilseed meal. Regarding strain selection, Bacillus spp. degrade macromolecular proteins and inhibit microbial contamination through protease and antimicrobial peptide production. Lactobacillus spp. enhance flavor and safety by producing acids and flavor compounds. Aspergillus spp. decompose cell walls and degrade phytate using their cellulase and phytase systems. For fermentation strategies, mixed fermentation achieves functional complementarity, enzyme–fungus synergy enhances substrate conversion, segmented fermentation optimizes the microbial environment, and physical field assistance boosts enzyme activity, collectively improving fermentation efficiency and nutritional quality. In product applications, fermented oilseed meal serves as both high-quality protein feed and a source of functional peptides and active polysaccharides with antioxidant and immunomodulatory activities, showing potential for functional foods and biomedicine. In conclusion, SSF technology effectively degrades anti-nutritional factors, improving the nutritional value and adding value to oilseed meal, thus representing a key strategy for resource conversion. Future efforts should prioritize high-performance strain selection, intelligent process monitoring, and green preparation of active products to promote industrial application and sustainable development. Full article

We carried out carbohydrate composition and carbohydrate linkage analyses on Neurospora crassa cell walls from vegetative hyphae, conidia (asexual spores), perithecia (female mating structures), and ascospores (sexual spores). We show that the composition and structure of the cell wall undergo dramatic changes during the N. crassa life cycle. All the cell walls contain β-1,3-glucan and mixed β-1,3-/β-1,4-glucan (lichenin). The conidia cell walls and perithecia cell walls also contain α-1,3-glucan. β-1,3-glucan was the most abundant polysaccharide in the vegetative hyphae cell walls and mixed β-1,3-/β-1,4-glucan was the most abundant polysaccharide in the perithecia and ascospore cell walls. Chitin was a major polysaccharide in the ascospore cell walls. Ascospore and perithecia cell walls also contained melanin as a structural element. We conclude that the composition and structure of the cell wall changes dramatically as cells proceed through the various stages of the N. crassa life cycle. Full article

Endo-β-1,4-mannanases (MANs) are glycoside hydrolase family 5 (GH5) enzymes that degrade cell wall mannan polysaccharides and participate in plant growth and stress adaptation. This gene family has not been systematically characterized in common wheat (Triticum aestivum L.). Here, we identified 24 TaMAN genes (TaMAN1–TaMAN24) genome-wide and analyzed their phylogeny, gene structures, chromosomal distribution, synteny, and promoter cis-acting elements. Expression profiles under biotic and abiotic stresses were investigated using public databases, salt-stress RNA-seq, and RT-qPCR. TaMAN proteins (386–475 aa) were mainly predicted to localize in the extracellular space. Phylogenetic analysis divided them into three groups, with Groups II and III representing monocot-specific expansions. Family expansion was driven primarily by whole-genome duplication, supplemented by tandem duplication on homoeologous group 6. Promoters were enriched in hormone- and stress-responsive cis-acting elements (ABRE, as-1/CGTCA-motif, W box). TaMAN1, TaMAN5, TaMAN8, TaMAN9, TaMAN16 and TaMAN19 were significantly induced by powdery mildew, while TaMAN3, TaMAN4 and TaMAN19–TaMAN22 rapidly responded to salt stress. This study provides candidate genes for disease-resistant and salt-tolerant wheat breeding. Full article

β-1,6-Glucan is a functionally crucial polysaccharide of the fungal cell wall, although typically less abundant than β-1,3-glucan and chitin, its content, chain length, and branching vary considerably among species. Structurally, it serves as a covalent cross-linker tethering the external mannoprotein layer to the internal β-1,3-glucan-chitin network, contributing to cell wall integrity and plasticity. Biosynthetically, unlike chitin and β-1,3-glucan, which are synthesized by the plasma membrane-associated synthases, β-1,6-glucan biosynthesis depends on a multi-protein cooperative network spanning the endoplasmic reticulum (ER), Golgi, and cell surface, whose core catalytic machinery remains incompletely defined. Genetic and in vitro reconstitution studies have begun to delineate the contributions of ER-resident proteins (Kre5, Big1, Cwh41/Gls1, Rot2/Gls2, and Cne1), Golgi-localized Kre6/Skn1 family members, and cell-surface components (Kre9, Knh1, Kre1, and Kre11). Functionally, its biological roles are established by two complementary lines of evidence, namely enzymatic digestion by endogenous or exogenous β-1,6-glucanases and inactivation of the biosynthetic machinery. Collectively, these studies show that β-1,6-glucan is essential for cell wall architecture, GPI-anchored protein localization, fungal growth, morphogenesis, and virulence, and acts as a potent immunomodulatory molecule at the fungus–host interface. Elucidating its structure, biosynthesis, and function will advance fungal cell wall biology. Full article

Cell-wall polysaccharide O-acetylation contributes to cell-wall assembly, organ development, and plant–pathogen interactions, but the cucumber TBL gene family remains poorly characterized. Here, 37 CsTBL genes were identified genome-wide and analyzed using phylogenetic, syntenic, conserved-motif, gene-structure, promoter, protein-structure, Gene Ontology, and transcriptome approaches, followed by RT-qPCR analysis after powdery mildew inoculation. All CsTBL proteins contained the conserved GDS and DxxH motifs, whereas accessory motifs and predicted structural features varied among clades. Intraspecific analysis identified dispersed, WGD/segmental, and tandem duplication categories, and cross-species synteny was more extensive with melon than with Arabidopsis. Homology-derived annotations associated CsTBL genes with cell-wall polysaccharide metabolism, Golgi/endomembrane compartments, and O-acetyltransferase activity, including six genes assigned to xylan O-acetyltransferase-related annotations. Expression profiling revealed tissue- and developmental-stage-dependent patterns, whereas the publicly available powdery mildew RNA-seq dataset provided descriptive temporal expression profiles in Podosphaera xanthii-inoculated samples. Independent RT-qPCR analysis using time-matched mock controls revealed distinct post-inoculation responses among six selected genes. Relative to the corresponding mock controls, CsTBL2 was consistently repressed; CsTBL15 showed transient induction at 1 dpi followed by repression; CsTBL24 exhibited a biphasic response; CsTBL25 was induced at all sampled post-inoculation time points; CsTBL26 showed progressive induction; and CsTBL30 reached its highest observed expression level at 3 dpi. Integrated functional annotation and expression evidence highlighted CsTBL26 as a priority candidate for further functional characterization, while CsTBL24 and CsTBL25 represented fruit-associated candidates with distinct powdery mildew responses; CsTBL30 remained an additional strongly infection-responsive candidate. These findings provide an evolutionary and expression-based framework for the functional characterization of the cucumber TBL gene family. Full article

Carbohydrates are among the most highly oxygenated biomolecules in nature, possessing dense arrays of hydroxyl, ether, carbonyl, carboxylate, phosphate, and sulfate functionalities that govern hydration, hydrogen bonding, molecular recognition, and supramolecular organization. Their stereochemically organized oxygen-donor groups provide numerous appropriately oriented diol motifs capable of selective and reversible coordination with boric acid and borate ions. This review examines the structural and physicochemical principles underlying carbohydrate–borate interactions, with particular emphasis on oxygen-rich biological interfaces. Pentoses, hexoses, oligosaccharides, polysaccharides, glycolipids, and membrane-associated glycoconjugates are considered to illustrate how hydroxyl-group orientation, molecular conformation, pH, hydration, and local environment determine borate recognition, complex stability, and dynamic assembly. Evidence from NMR and other spectroscopic methods, crystallography, mass spectrometry, calorimetry, and molecular simulations demonstrates that borate coordination follows common stereochemical and thermodynamic principles despite the remarkable structural diversity of carbohydrates. Biological examples include borate-mediated crosslinking in plant cell walls and interactions involving microbial carbohydrates, marine polysaccharides and glycoconjugates, photosynthetic membrane lipids, and cyanobacterial heterocyst glycolipids. Particular attention is given to distinguishing experimentally established borate complexes from membrane-associated interactions that remain proposed and require further characterization. Reversible borate crosslinking of oxygen-rich carbohydrate networks also provides the chemical basis for emerging applications in responsive hydrogels, biosensors, supramolecular assemblies, drug-delivery systems, and functional biomaterials. Collectively, the available evidence indicates that the spatial organization of oxygen donor atoms within carbohydrates provides the molecular basis for selective borate recognition, whereas boron can convert this functionality into reversible higher-order organization. This oxygen-centered perspective integrates coordination chemistry, glycobiology, membrane biology, and materials science into a unified framework for understanding carbohydrate–borate interactions in natural and engineered systems. Full article

Plant cell walls play a crucial role in plant development and evolution. This structure is primarily composed of proteins and polysaccharides, including cellulose, hemicellulose, and pectins. Homogalacturonan (HG), the most abundant pectin in the primary cell wall, is synthesized by α -1,4-D-GALACTURONOSYLTRANSFERASE (GAUT) enzymes, methylesterified, and subsequently secreted into the apoplast. The dynamics of pectin methylesterification is regulated by enzymes such as PECTIN METHYLESTERASES (PMEs) and PECTIN METHYLESTERASE INHIBITORS (PMEIs). Across plant evolution and development, different cell types display distinct domains of pectin methylesterification. The binding of de-methylesterified pectins to the Catharanthus roseus RECEPTOR-LIKE KINASE 1-LIKE (CrRLK1L) proteins and RAPID ALKALINIZATION FACTOR (RALF) peptides is involved in pectin signaling and cell wall integrity maintenance during developmental processes. While phylogenetic studies highlight molecular innovations in pectin metabolism, functional studies remain scarce outside of angiosperms. Furthermore, the explicit role of de-methylesterified pectin in coupling cell wall structure to intracellular signaling has only been demonstrated in angiosperms. Comparative functional studies addressing key evolutionary transitions will ultimately reveal how pectin metabolism has contributed to morphological innovations across plant evolution. Full article

This study evaluated the synergistic effects of sodium chloride (NaCl) and cytidine monophosphate (CMP) on enhancing the co-production of astaxanthin and fatty acids while suppressing secondary cell wall (SCW) formation in Haematococcus lacustris (synonym: H. pluvialis) under high-light stress. An orthogonal design identified the optimal combination (0.5 g/L NaCl and 0.5 mM CMP), which significantly increased astaxanthin yield by over 35.6% and total fatty acid yield by 28%, while maintaining 96.8% of cells in motile state (SCW-deficient). Physiological analyses revealed elevated reactive oxygen species levels, concomitant with higher actual photochemical efficiency (Fv′/Fm′) and relative electron transport rates II (rETR(II)) along with enhanced non-photochemical quenching (NPQ) capacity, and metabolic reprogramming characterized by the accumulation of lipids, sugars, and starch alongside decreased protein yield. Metabolomics indicated reduced carbon supply for SCW polysaccharide biosynthesis, coupled with decreased protein yield and altered amino acid profiles characteristic of nitrogen-limited metabolism, which collectively favored the reallocation of carbon resources toward nitrogen-free high-value products. Transcriptomics confirmed the downregulation of SCW component biosynthetic genes and the upregulation of the methylerythritol phosphate (MEP) pathway and astaxanthin biosynthetic pathway. Scale-up experiments validated this strategy for producing astaxanthin-rich motile cells, offering a promising approach for microalgal biorefinery. Full article

Postbiotic preparations contain inanimate microbial cells and a diverse mixture of cell-wall structures, proteins, polysaccharides, lipids, metabolites, and vesicle-associated materials. Although many of these components have been proposed as key bioactives, most are identified through compositional profiling, enrichment in active fractions, or testing of purified molecules. Such findings demonstrate biological activity but do not necessarily show that a candidate contributes to the effect of the original preparation. This review examines the experimental approaches used to narrow candidate lists and evaluate functional contribution, including phenotype-guided comparison, activity-guided fractionation, selective depletion, multi-omics profiling, structural characterization, dose–response testing, mechanistic intervention, and reconstitution. A structured narrative search of Web of Science Core Collection, PubMed, and Scopus through 30 March 2026, supplemented by citation tracking, identified the relevant literature; 15 representative primary studies that examined defined candidates and provided evidence beyond compositional detection were selected and appraised across seven preparation-level attribution domains. An appraisal of representative studies shows that current evidence largely supports the activity of individual candidates, whereas preparation-level attribution remains uncommon. Stronger evidence requires quantification of the candidate in the source material, selective removal with appropriate controls, and restoration at a preparation-relevant dose. Structural heterogeneity, processing history, molecular state, dose, and experimental context must also be considered. This evidence-based approach can support bioactive-component validation, batch consistency, and the design of future preclinical and human studies. Full article

Crop straw is an abundant lignocellulosic resource, but its efficient bioconversion is hindered by the recalcitrant structure of plant cell walls. This study integrated degradation phenotyping, enzyme activity assays, whole-genome analysis, and comparative transcriptomics to link the wheat-straw degradation performance of strain XH2 with its enzymatic and molecular responses. Strain XH2 was isolated from fully decomposed compost collected in Anhui Province, China, selected based on the formation of a distinct hydrolysis halo on CMC-Congo red agar, and deposited in the China Center for Type Culture Collection (CCTCC) under accession number CCTCC M 2025519. Morphological, cultural, phylogenetic, and genomic analyses identified strain XH2 as Streptomyces thermocarboxydus. Its degradation capacity was evaluated during 28 days of cultivation by measuring straw degradation, lignocellulosic components, scanning electron microscopy (SEM), and extracellular enzyme activities. S. thermocarboxydus XH2 caused marked disruption of the wheat-straw surface and achieved a degradation rate of 31.45%. Cellulose and hemicellulose contents decreased from 41.10% to 28.87% and from 30.72% to 16.85%, respectively, whereas lignin decreased from 8.28% to 6.30%. Endoglucanase activity, filter paper activity (FPase, an indicator of total cellulase activity), and xylanase activity peaked on day 7, reaching 35.99, 17.68, and 37.01 U/mL, respectively. Genome analysis revealed multiple genes encoding cellulases and hemicellulases. Comparative transcriptomic analysis after 72 h of cultivation in wheat-straw medium identified 1614 differentially expressed genes relative to Gause No. 1 medium, with major enrichment in ABC transporters and fructose and mannose metabolism. Most genes associated with polysaccharide degradation were upregulated. These findings link the degradation phenotype of S. thermocarboxydus XH2 to its enzymatic and molecular responses and support its further evaluation as a candidate for wheat-straw bioconversion under greenhouse and field conditions. Full article

As LEDs are increasingly used in mushroom production, understanding the blue-light response characteristics of the pathogenic fungus Trichoderma harzianum is important for mushroom cultivation management. In this study, T. harzianum was cultured under blue LED conditions (460 nm), with darkness as the control, and its growth, morphology, and transcriptomic responses were compared. Blue LED exposure reduced colony diameter by 21.6% and 25.2% on days 1 and 2 of cultivation, respectively, and induced sporulation on day 3. RNA-seq Trinity gene-level features were quantified, and 23,086 and 34,839 genes showed higher and lower expression under blue LED illumination, respectively. Gene Ontology (GO) analysis of candidates selected using the criteria TPM ≥ 15 and |log2FC| ≥ 1 showed that the candidates with increased expression blue LED illumination were associated with transport and xenobiotic transport, whereas the candidates with decreased expression were associated with filamentous growth, cell wall polysaccharide biosynthetic process, and UDP-glucosyltransferase activity. Among the highly responsive candidates selected using the criteria TPM ≥ 15 and |log2FC| ≥ 3, carbohydrate-active enzyme (CA-Zyme)-related genes were identified, including glycosyltransferase family (GT) 8, GT35, glycoside hydrolase family (GH) 16, GH18, GH76, and multicopper oxidase. In contrast, the candidates with decreased expression included GT2, GT20, GT35, carbohydrate esterase family 5, and GMC oxidoreductase. RT-qPCR analysis of the selected candidate genes supported the RNA-seq-based expression trends. In addition, in the RNA-seq dataset, the expression levels of the blue light response-related genes BLR-1, BLR-2, and ENV1 increased by 2.8-, 1.9-, and 4.2-fold, respectively. These findings provide phenotypic and molecular candidates for future functional studies of the blue-light response in T. harzianum. Full article

Precious metal nanoparticles (PMNPs), particularly silver, gold, palladium, and platinum nanoparticles, have attracted considerable attention owing to their unique physicochemical properties and broad applications in catalysis, environmental remediation, and biomedicine. Conventional physical and chemical synthesis methods often require substantial energy input, harsh reaction conditions, and generate large volumes of metal-containing wastewater, raising concerns regarding sustainability and environmental impact. Microbial synthesis provides a sustainable alternative by using microorganisms as natural biofactories to convert toxic precious metal ions into valuable nanoparticles under mild conditions. This review summarizes recent advances in the microbial synthesis of PMNPs (Bio-PMNPs), focusing on biosynthetic mechanisms in bacteria, algae, and fungi. Bio-PMNPs formation involves both extracellular and intracellular reduction processes, coupled with electron transfer mediated by reductases and other redox-active biomolecules. Functional groups present on microbial cell walls, as well as proteins, polysaccharides, enzymes, and other metabolites, play important roles in the adsorption, reduction, stabilization, and growth of nanoparticles. We further highlight the applications of Bio-PMNPs in antimicrobial activity, cancer therapy, pollutant degradation, heavy-metal removal, and catalytic enhancement of organic synthesis. Despite substantial progress, challenges remain in controlling nanoparticle size and morphology, elucidating biosynthetic mechanisms, and achieving large-scale production. Future integration of synthetic biology, metabolic engineering, and process optimization is expected to improve the controllability, stability, scalability, and biosafety of Bio-PMNPs production. Full article

Gene editing techniques are well-developed for model microalgae like Chlorella and Chlamydomonas. However, for the high-value species Porphyridium purpureum, its thick cell wall poses a significant barrier to genetic manipulation. Overcoming this challenge requires a robust method for preparing highly viable protoplasts. To generate protoplasts of P. purpureum, a targeted enzymatic lysis was applied based on the structural composition of the cell wall in this study. The results of single-factor experiments showed that a high protoplast yield (up to 43.55%) could be achieved under the following conditions: a total cellulase and macerozyme concentration of 2%, a cellulase-to-macerozyme ratio of 3:7, and a treatment time of 8 h in 0.2 mol/L KCl. Subsequently, Response Surface Methodology further optimized the enzymatic lysis conditions, yielding the optimal combination: a fixed combined concentration of cellulase and macerozyme at 2.2% in 0.2 mol/L KCL solution, a ratio of approximately 1:3, and an 8 h treatment, achieving a protoplast yield of 49.44%. Transmission electron microscopy, field emission scanning electron microscopy and Evans Blue staining confirmed that the protoplasts had smooth surfaces, no extracellular polysaccharide residues, and intact membranes and organelles. Furthermore, the optimal regeneration medium was ASW medium supplemented with 0.2 mol/L KCl, which might create a stable microenvironment for protoplast regeneration by balancing baseline osmotic pressure and ionic environment. This study established an effective protocol for protoplast preparation and regeneration, thereby facilitating the development of gene-editing tools for P. purpureum. Full article

Deep eutectic solvents (DESs) have emerged as promising green extraction media for natural bioactive compounds, offering tunable physicochemical properties, biocompatibility, and lower toxicity than conventional organic solvents. However, the high viscosity of DESs limits mass transfer efficiency, necessitating integration with auxiliary technologies to overcome this intrinsic constraint. Unlike previous reviews that focus on DESs coupled with a single auxiliary technique, this review for the first time integrates DESs with ultrasound, microwave, enzymatic assistance, and multi-technique hybrid systems into a unified framework, critically comparing their enhancement mechanisms, applicability boundaries, and industrial feasibility. This review systematically examines the non-covalent interactions between DES components and target compounds, including hydrogen bonding, van der Waals forces, and electrostatic interactions, and discusses how these interactions guide the rational selection of hydrogen bond acceptors (HBAs) and donors (HBDs) for specific compound classes. We analyze the distinct mechanisms by which ultrasound, microwave, and enzymatic assistance synergistically enhance DES extraction performance, with particular attention to viscosity reduction, cell wall disruption, and biocatalytic compatibility. Recent advances in the extraction of polyphenols, alkaloids, terpenoids, and polysaccharides are summarized to illustrate the practical application of these principles. Finally, we discuss current challenges in industrial scale-up, including solvent recovery, equipment adaptation for high-viscosity media, and regulatory considerations, and outline future directions toward intelligent solvent design and continuous processing. By integrating molecular-level mechanistic insights with process engineering perspectives, this review provides a comprehensive framework for the optimization and application of DES-based extraction technologies. Full article

Edible mushroom polysaccharides have attracted considerable attention because of their diverse biological activities, particularly their antioxidant potential. However, efficient extraction of these polysaccharides remains challenging due to the rigid chitin–β-glucan network of fungal cell walls. In this study, polysaccharides from Termitomyces albuminosus were extracted using hot water extraction (HWE), ultrasound-assisted extraction (UAE), and ultrasound-assisted aqueous two-phase extraction (UA-ATPE). Extraction conditions for each method were optimized using Box–Behnken response surface methodology, and the effects of different extraction strategies on polysaccharide yield, physicochemical properties, and antioxidant activity were systematically compared. Among the three methods, UAE produced the highest polysaccharide yield (110.32 ± 3.68 mg/g). The extraction strategy significantly influenced the molecular weight distribution and monosaccharide composition of the crude polysaccharides. The crude UAE extract was further purified by DEAE-52 anion-exchange chromatography, yielding the major antioxidant-active fraction eluted with 0.1 M NaCl (designated ATPs-0.1M), which was identified as an acidic heteropolysaccharide with an average molecular weight of 6.37 kDa and composed primarily of glucose, mannose, galactose, xylose, glucuronic acid, rhamnose, and fucose. In vitro antioxidant assays demonstrated that TAPs-0.1M exhibited stronger DPPH radical scavenging, hydroxyl radical scavenging, and ferric reducing activities than the other purified fractions under the tested conditions. The results indicate that different extraction strategies are associated with distinct physicochemical characteristics and antioxidant activities of T. albuminosus polysaccharides. These findings provide a practical basis for selecting appropriate extraction methods and support the further development of T. albuminosus polysaccharides as natural antioxidant ingredients. Full article