Cassava residue (CR), a major agro-industrial byproduct rich in carbohydrates but low in protein and lipids, has limited feed value. Bacillus subtilis producing poly-γ-glutamic acid (γ-PGA) generates active components that improve animal growth, immunity, and health. This study used solid-state fermentation with B. subtilis SCP010-1, a high γ-PGA–producing strain, to enhance CR quality. Animal experiments, untargeted metabolomics, and metagenomics were used to systematically evaluate the nutritional quality, feeding safety, and gut regulatory mechanisms of fermented cassava residue (FCR). γ-PGA production in the scale-up FCR reached 56.36 g/kg, while free amino acids, and small peptides increased significantly from 17.84 μg/g, 10.38 mg/g, and 50.23 g/kg to 290.87 μg/g, respectively. Cyanide, phytic acid, and tannins were reduced to 7.38 mg/kg, 1.63 mg/kg, and 0.04%. Metabolomic analysis revealed upregulated amino acids and their derivatives alongside downregulated organic acids and plant-derived metabolites, indicating activated amino acid metabolism and γ-PGA biosynthesis. A 30-day mouse trial showed that 20 and 40% CR diets inhibited growth, impaired liver function, and reduced immunity, whereas FCR groups showed comparable improvements to the control, with 40% as the optimal inclusion level. Metagenomics further indicated that FCR reshaped gut microbiota by enriching beneficial genera such as Dubosiella and Bacillus, positively correlating with body weight gain and negatively with serum ALT, AST, and lipid profiles (p < 0.05). In conclusion, solid-state fermentation markedly enhances the nutritional value and biological effects of cassava residue, providing an effective strategy for its high-value utilization.

5-Aminolevulinic acid (5-ALA) is a valuable precursor for pharmaceuticals and agriculture, but its microbial production is limited by tight coupling to essential heme biosynthesis. Here, we introduce a systematic, activity-graded tuning strategy for porphobilinogen synthase (PBGS, encoded by hemB) to decouple 5-ALA synthesis from heme metabolism in Corynebacterium glutamicum. Guided by structural and functional analyses, PBGS variants with progressively reduced activities were constructed to investigate the quantitative relationship between enzyme activity, cell growth, and 5-ALA accumulation. Controlled attenuation of PBGS activity maintained essential metabolism while markedly enhancing 5-ALA accumulation and minimizing porphyrin by-products. The engineered strain FA3 [hemB(D128E), hemA overexpression] achieved an optimal balance of growth and productivity. Metabolomic profiling confirmed that PBGS downregulation primarily suppressed porphyrin biosynthesis with minimal impact on central carbon metabolism. Subsequent metabolic and process optimizations, including gdhA and aceA deletion, dynamic rhtA expression, and cultivation control, further boosted production to 14.44 g/L 5-ALA in shake-flask culture, representing the highest shake-flask titer reported to our knowledge for C. glutamicum under similar conditions. This work provides the first systematic dissection of PBGS activity-dependent metabolic regulation and demonstrates that graded control of an essential enzyme enables rational metabolic decoupling, offering a broadly applicable framework for robust, high-yield microbial production of valuable compounds.IMPORTANCE5-Aminolevulinic acid (5-ALA) is an important precursor with pharmaceutical and agricultural applications, but microbial production is often constrained by its tight linkage to essential heme metabolism. Here, we systematically tuned porphobilinogen synthase activity to decouple 5-ALA accumulation from excessive porphyrin flux while maintaining cell growth. This strategy not only enabled the highest reported 5-ALA titer in Corynebacterium glutamicum but also highlights a broadly applicable framework for rationally engineering essential metabolic enzymes to achieve robust, high-yield microbial production of valuable compounds.

Hepatocellular carcinoma (HCC) remains a therapeutic challenge due to late-stage diagnosis and suboptimal response to standard therapies. Resveratrol, a plant-derived polyphenol, suppresses proliferation of HCC cells by inducing apoptosis and autophagy. However, the regulatory mechanism that integrates these two processes is poorly understood. This study aimed to elucidate how resveratrol coordinately regulates apoptosis and autophagy in HCC cells. Using integrated network pharmacology and QIAGEN Ingenuity Pathway Analysis (IPA), TP53 was predicted as the central hub target gene of resveratrol in HCC, where it coordinated both apoptosis and autophagy. Molecular docking and molecular dynamics simulation confirmed direct and stable binding of resveratrol to p53 protein. Functional validation in vitro revealed that resveratrol significantly (P < 0.01) inhibited the viability of p53-wild-type HepG2 cells, accompanied by mRNA upregulation of pro-apoptotic and autophagy-related genes (BAX, CASP9, CASP3, ATG5), with concordant changes at the protein level (upregulated Bax and ATG5 proteins, increased ratios of Bax/Bcl-2, cleaved-Caspase 9/Caspase 9, cleaved-Caspase 3/Caspase 3, and LC3B-II/I, decreased p62 protein). These effects were strictly p53-dependent, as they were absent in p53-null Hep3B cells and significantly (P < 0.05) attenuated upon pharmacological inhibition of p53 in HepG2 cells. Mechanistically, resveratrol activated p53 not by increasing its protein level but by enhancing its acetylation at Lysine 382. This study established p53 acetylation as a critical switch through which resveratrol coordinately induced apoptosis and autophagy. These findings provide a mechanistic framework for anti-HCC effect of resveratrol and underscore the therapeutic relevance of p53 activation pathways in HCC.

β-cypermethrin (β-CY) is a widely used pyrethroid insecticide, yet the regulatory mechanisms that determine microbial degradation efficiency remain unclear. Here, we examined the role of the global nutrient-responsive regulator CodY in β-CY degradation by Bacillus cereus GW-01 using a wild-type strain, an in-frame codY deletion mutant, and a complemented strain. Loss of codY shortened the growth lag phase under β-CY stress and accelerated β-CY removal across 50-200 mg/L, reducing the apparent half-life from 3.61 to 12.62 d in the wild type to 2.42-9.61 d in ΔcodY. Complementation largely restored the wild-type phenotype, confirming CodY as a negative regulator of β-CY dissipation. Transcriptomic and physiological analyses showed that ΔcodY reallocated cellular functions toward branched-chain amino acid metabolism, transport, redox adjustment, envelope remodeling, adhesion, and biofilm formation. Consistently, the mutant exhibited higher cell-surface hydrophobicity, stronger auto-aggregation, enhanced biofilm formation, increased superoxide dismutase (SOD) activity, and lower lipid peroxidation. In soil microcosms, ΔcodY also outperformed the wild type in both non-sterilized and sterilized soils, shortening β-CY half-lives by 13.5% and 22.8%, respectively. Community profiling further showed that ΔcodY altered bacterial and fungal succession during remediation, with stronger early selection, later bacterial richness recovery, and a more modular co-occurrence network. These results show that CodY restricts β-CY degradation by constraining both catabolic readiness and surface-associated stress adaptation. Targeting global regulatory nodes may therefore improve microbial remediation of hydrophobic pesticide residues in soil.

This study focuses on the glutamate-dependent strain Bacillus subtilis SCP017-03, systematically investigating its metabolic mechanism for synthesizing γ-polyglutamic acid (γ-PGA) in the presence of exogenous glutamate, as well as optimizing its fermentation conditions. Metabolomic analysis revealed that glutamate addition significantly altered the cellular metabolic profile, with 480 out of 1674 metabolites showing differential expression. Notably, pathways such as the TCA cycle, glycolysis, glutathione metabolism, and amino acid metabolism were significantly upregulated, enhancing precursor supply and energy metabolism, thereby promoting γ-PGA synthesis. Based on these findings, fermentation conditions were optimized in a 5-L bioreactor. Yeast extract was identified as the optimal nitrogen-rich nutrient, and at an addition level of 7.5 g/L, the γ-PGA yield reached 87 g/L. The optimal conversion efficiency and yield were achieved with a 5

Introduction:China's rapid urbanization has led to the conversion of extensive farmland on urban fringes into non-grain uses, exacerbating the scarcity of arable land resources. Reclaiming these abandoned or underutilized areas presents a viable solution. However, many of these lands are contaminated with construction debris and have uneven soil quality, rendering them unsuitable for crop cultivation. This study aims to investigate the effects of γ-polyglutamic acid (γ-PGA) on improving such soils. Methods:A 6-month field experiment was conducted on green spaces with mixed construction waste in Chengdu's urban ring. The study analyzed the impact of γ-PGA on soil bacterial communities, metabolites, and physicochemical properties during different wheat growth stages, namely tillering, jointing, flowering, and maturity. Results:γ-PGA significantly increased soil organic matter, total nitrogen, nitrate nitrogen, and alkali-hydrolyzable nitrogen. It also boosted enzyme activities such as urease, sucrase, and alkaline phosphatase. The soil mechanical structure improved, with increases in clay, sand, and macroaggregates. As wheat grew, the fractal dimensions of soil volume and infiltration performance increased, while bulk density decreased, indicating enhanced water retention and gas exchange. Beneficial microorganisms like Actinobacteria and Devosia increased in abundance, promoting soil fertility. Metabolomics analysis revealed that γ-PGA enriched pathways involved in carbohydrate digestion, starch metabolism, and nucleotide processes, creating a more favorable environment for plant growth. Discussion:This research underscores the crucial role of γ-PGA in soil restoration and fertility enhancement. The findings provide valuable insights for reclaiming non - grain farmland, offering a potential solution to the challenge of arable land shortage caused by urbanization. The study's results contribute to the existing knowledge on soil improvement techniques and have practical implications for sustainable agricultural development in urbanized regions. However, further research could explore the long-term effects of γ-PGA application and its applicability in different soil types and environmental conditions.

Poly-gamma-glutamic acid (γ-PGA) is mainly synthesized by glutamate-dependent strains in the manufacturing industry. Therefore, understanding glutamate-dependent mechanisms is imperative. In this study, we first systematically analyzed the response of Bacillus subtilis SCP017-03 to glutamate addition by comparing transcriptomics and proteomics. The introduction of glutamate substantially altered gene expression within the central metabolic pathway of cellular carbon. Most genes in the pentose phosphate pathway (PPP), tricarboxylic acid (TCA) cycle, and energy-consuming phase of the glycolysis pathway (EMP) were down-regulated, whereas those in the energy-producing phase of glycolysis and those responsible for γ-PGA synthesis were up-regulated. Based on these findings, the fermentation conditions were optimized, and γ-PGA production was improved by incorporating oxygen carriers. In a batch-fed fermentor with glucose, the γ-PGA production reached 95.2 g/L, demonstrating its industrial production potential. This study not only elucidated the glutamate dependence mechanism of Bacillus subtilis but also identified a promising metabolic target for further enhancing γ-PGA production.

Atractylodes macrocephala Koidz. (Baizhu, BZ) is a renowned herb in Traditional Chinese Medicine. Its bioactive components include volatile oils, lactones, and polysaccharides, with recent studies focusing on how processing techniques like stir-frying influence these compounds' properties. This study investigates the effects of stir-frying on the structural, chemical, and functional characteristics of BZ polysaccharides (BZPs), aiming to optimize their bioactivity. BZ was subjected to stir-frying at 180 degrees C for varying durations (0, 13, 26, 39, 52 min), followed by ultrasonic extraction and purification via gel filtration chromatography. Five polysaccharide fractions (BZP-1 to BZP-5) were obtained, each representing different molecular weights and monosaccharide composition. Analysis of the apparent morphology using SEM and AFM revealed significant changes in surface texture and particle aggregation with increasing stir-frying time. FT-IR and NMR spectroscopy confirmed structural stability, with key functional groups intact. XRD and Congo red analysis revealed changes in crystallinity and triple-helix formation, while thermal and rheological studies indicated distinct thermal stability and flow behavior among the fractions. Notably, BZP-5 exhibited the highest alpha-amylase inhibition activity. This study highlights how stirfrying alters the physicochemical properties of BZPs, offering insights into optimizing processing conditions to enhance the therapeutic potential of BZ in various applications.

γ-Polyglutamic acid (γ-PGA) is a versatile biopolymer with a wide range of applications. However, its large-scale production remains limited by high costs and low process efficiency. Wheat malt, rich in endogenous amylases and widely used in beer brewing, has seen limited applications in starch hydrolysis for microbial fermentation. This study developed a cost-effective process for γ-PGA production using corn starch liquefied by malt-derived enzymes as the carbon source. Liquefaction was conducted at 65 °C and pH 6.5 with a solid-to-liquid ratio of 1:6 and a malt-to-starch ratio of 1:7 for 5 h, yielding a solution with a dextrose equivalent (DE) of 21.2

Microorganisms with chitin-degrading capabilities play a crucial role in the biological control of crop pests and diseases as well as in the treatment of organic waste. In this study, a chitin-degrading bacterium, designated L2-2, was isolated from the intestine of Odorrana margaretae collected in Mount Emei, Sichuan, China. Based on physiological and biochemical characteristics, 16S rRNA gene sequencing, and phylogenetic analysis of 31 conserved housekeeping genes in the whole genome, strain L2-2 was identified as a member of the genus Roseateles, named Roseateles sp. L2-2. This strain is able to grow on agar medium with colloidal chitin as the sole carbon source and form clear hydrolysis zones. After optimizing fermentation conditions (including concentrations of nitrogen and carbon sources, culture time, and pH), the enzyme activity was increased to 3.46 U/mL, which was 24 times higher than the initial enzyme activity. Functional genome annotation showed that the strain contains genes encoding endochitinases of the GH18, GH23, and GH46 families, as well as genes encoding β-glucosidases of the GH1, GH2, GH3, and GH109 families, indicating its genetic basis for chitin-degrading potential. This study expands the diversity of known chitin-degrading bacteria and provides a promising microbial resource for the bioremediation of chitinous waste and sustainable pest control in agriculture.

Starch, a crucial raw material, has been extensively investigated for biotechnological applications. However, its application in γ-polyglutamic acid (γ-PGA) production remains unexplored. Based on γ-PGA output of Bacillus subtilis SCP010-1, a novel asynchronous saccharification and fermentation process for γ-PGA synthesis was implemented. The results revealed that a starch concentration of 20

Cellulolytic microorganisms play a crucial role in agricultural waste disposal. Strain QXD-8T was isolated from soil in northern China. Similarity analyses of the 16S rRNA gene, as well as the 120 conserved genes in the whole-genome sequence, indicate that it represents a novel species within the genus Microbacterium. The Microbacterium sp. QXD-8T was able to grow on the CAM plate with sodium carboxymethyl cellulose as a carbon source at 15 °C, forming a transparent hydrolysis circle after Congo red staining, even though the optimal temperature for the growth and cellulose degradation of strain QXD-8T was 28 °C. In the liquid medium, it effectively degraded cellulose and produced reducing sugars. Functional annotation revealed the presence of encoding genes for the GH5, GH6, and GH10 enzyme families with endoglucanase activity, as well as the GH1, GH3, GH39, and GH116 enzyme families with β-glucosidase activity. Additionally, two proteins in the GH6 family, one in the GH10, and two of nine proteins in the GH3 were predicted to contain a signal peptide and transmembrane region, suggesting their potential for extracellularly degrade cellulose. Based on the physiological features of the type strain QXD-8T, we propose the name Microbacterium psychrotolerans for this novel species. This study expands the diversity of psychrotolerant cellulolytic bacteria and provides a potential microbial resource for straw returning in high-latitude areas at low temperatures.

The incidence of esophageal cancer continues to increase worldwide. Current therapeutic approaches have limited efficacy, so in order to search for better markers of the disease, it is necessary to further elucidate its molecular pathogenesis. Regulation of gene expression by long non-coding Rnas plays a role in many diseases, however the role in esophageal cancer is unclear. The aim of this study was to elucidate the role and regulatory mechanism of long non-coding RNA NRSN2-AS1 in the progression of esophageal cancer. By real-time quantitative PCR, immunohistochemistry, RNA interference, western blotting, and double luciferase reporter gene analysis, we found that NRSN2-AS1 was up-regulated in esophageal cancer tissues and cell lines, and was closely related to disease stage and prognosis. Functional studies have shown that the silencing of NRSN2-AS1 inhibits the proliferation of esophageal cancer cells, induces apoptosis, and prevents cell migration and invasion. In mouse models, NRSN2-AS1 also promoted tumor growth. The transcription factor TCFL5 upregulates the transcription of NRSN2-AS1, which acts as a sponge for microRNA(miR)-874-5p, thereby upregulating the expression of the oncogene RELT. Activation of the NRSN2-AS1/miR-874-5p/RELT regulatory axis was validated in vivo.

Kaempferitrin is an active component in Chenopodium ambrosioides, showing medicinal functions against liver cancer. This study aimed to identify the potential targets and pathways of kaempferitrin against liver cancer using network pharmacology and molecular docking, and verify the essential hub targets and pathway in mice model of SMMC-7721 cells xenografted tumors and SMMC-7721 cells. Kaempferitrin therapeutical targets were obtained by searching SwissTargetPrediction, PharmMapper, STITCH, DrugBank, and TTD databases. Liver cancer specific genes were obtained by searching GeneCards, DrugBank, TTD, OMIM, and DisGeNET databases. PPI network of "kaempferitrin-targets-liver cancer" was constructed to screen the hub targets. GO, KEGG pathway and MCODE clustering analyses were performed to identify possible enrichment of genes with specific biological subjects. Molecular docking and molecular dynamics simulation were employed to determine the docking pose, potential and stability of kaempferitrin with hub targets. The potential anti-liver cancer mechanisms of kaempferitrin, as predicted by network pharmacology analyses, were verified by in vitro and in vivo experiments. 228 kaempferitrin targets and 2186 liver cancer specific targets were identified, of which 50 targets were overlapped. 8 hub targets were identified through network topology analysis, and only SIRT1 and TP53 had a potent binding activity with kaempferitrin as indicated by molecular docking and molecular dynamics simulation. MCODE clustering analysis revealed the most significant functional module of PPI network including SIRT1 and TP53 was mainly related to cell apoptosis. GO and KEGG enrichment analyses suggested that kaempferitrin exerted therapeutic effects on liver cancer possibly by promoting apoptosis via p21/Bcl-2/Caspase 3 signaling pathway, which were confirmed by in vivo and in vitro experiments, such as HE staining of tumor tissues, CCK-8, qRT-PCR and western blot. This study provided not only insight into how kaempferitrin could act against liver cancer by identifying hub targets and their associated signaling pathways, but also experimental evidence for the clinical use of kaempferitrin in liver cancer treatment.

Soybean meal (SBM), a high-protein animal feed, contains several anti-nutritional factors, which limit its utili-zation. Poly-gamma-glutamic acid (gamma-PGA), a biological macromolecule, can significantly improve the health and growth benefits of animal feed. However, there are rare reports about SBM fermentation with gamma-PGA-producing bacteria to improve its nutritional quality. In this study, we isolated a glutamic acid-independent poly gamma-glutamic acid (gamma-PGA) producing Bacillus velezensis SCP024-S-4 bacterial strain and used it for solid fermentation of SBM. The results showed that the maximum gamma-PGA yield in fermented soybean meal (FSBM) reached up to 89.64 g/kg without adding glutamic acid. Meanwhile, the content of proteins, free amino acids and small peptides increased by 12.83%, 347.96 mu g/g and 108.11 mg/g, respectively. Soy globulin, 8-conglutinin and trypsin inhibitor all decreased below 3 mg/g. Mice were fed with CK (control diet), SBM and FSBM respectively. The average daily food intake in the FSBM, SBM, and CK groups were 7.68, 5.25, and 6.36 g, respectively. Compared with the CK group, the mice weight growth rate was significantly higher in the FSBM group. Mice blood and spleen tests showed no negative effect of FSBM. The high-throughput sequencing of mice intestinal microflora indicated that FSBM increased the richness of intestinal microbiota; especially, the types and quantities of Lactobacillus were significantly increased. This study provides a feasible strategy to improve the nutritional quality of SBM as an animal feed.

Uranium (U) is a non-essential and toxic element that can cause cell death in plants, but the mechanism is unclear. In the present study, we found that U triggered iron (Fe)- and reactive oxygen species (ROS)-dependent ferroptosis-like cell death in Vicia faba roots. The results showed that U entered V. faba root cells and even accumulated in the nucleus and organelles. U accumulation resulted in obvious changes in mitochondrial morphology, including shrunken shape, rupture of outer membrane, increased density of inner membrane and fuzzy crista. Compared with the control, the accumulation of Fe and ROS in V. faba roots increased after U exposure, while the peroxidase (POD) and glutathion peroxidase (GPX) activities decreased significantly, which was only 57.7 % and 14.3 % of control, respectively. Transcriptomic data showed that the expression of genes related to ROS production was mainly up-regulated (e.g. NDH, CCR, RbohB), while the expression of genes related to ROS scavenging was mainly down-regulated (e.g. GPX4, POD1, POD7). These results led to excessive accumulation of ROS in root cells and triggered ferroptosis-like cell death. The key mechanism of U triggering ferroptosis-like cell death was to increase Fe accumulation and decrease GPX activity, so the cell death was promoted by addition of Fe (FeSO4 and FeCl3), and was inhibited by the lipophilic antioxidants [ferrostatin (Fer-1) and Vitamin E (VE)] and the Fe chelators [ciclopirox olamine (CPX)]. In conclusion, we demonstrated for the first time that U triggered ferroptosis-like cell death in V. faba roots. Our results provide a new insight for revealing the toxicological mechanism of U and other heavy metals in plants.

The toxicity of uranium (U) to plants makes the phytoremediation effect of U contaminated soil unsatisfactory, and the understanding of the mechanism of U toxicity to plants is limited. In the present study, the effects of U on nitrogen (N) metabolism and endoplasmic reticulum (ER) protein homeostasis in radish (Raphanus sativus) and broad bean (Vicia faba) were analyzed. The results showed that the content of amine N was significantly increased in R. sativus root after U treatment, but significantly decreased in both root and leaf of V. faba, indicating that U had an adverse effect on the N nutrition in V. faba. After U treatment, the nitrate reductase (NR) activity in R. sativus roots and leaves was increased to 2.9 and 4.8 times of that in control group, but decreased by 26.9% and 74.3% in V. faba, respectively. The transcriptome sequencing results showed that 3 NR genes were up-regulated in R. sativus root, while 1 was down-regulated in V. faba after U treatment. In addition, U interfered with ER protein homeostasis and induced ER stress. The bZIP17/28 and bZIP60-mediated unfolded protein response (UPR) pathways were activated in R. sativus root. This promoted downstream ER associated degradation (ERAD) pathway, facilitating the degradation of unfolded (or misfolded) proteins, thereby alleviating ER stress. While in V. faba, U triggered severe programmed cell death through the induction of ER stress, which was significantly alleviated by exogenous addition of the chemical chaperone 4-phenylbutyric acid. Overall, more efficient N assimilation activity and ER protein homeostasis maintenance mechanism (especially ERAD) may be one of the key mechanisms for R. sativus tolerance to U stress. This study for the first time revealed the toxicological mechanism of U in plants in terms of N metabolism and ER protein homeostasis.

制备两种型号的包埋了丁苯酞的两亲性碳质微球Ⅰ-ACPs@NBP和Ⅱ-ACPs@NBP,研究其包埋率和缓释性.先用丙酮对酵母细胞进行预处理,然后再将酵母细胞进行温和的水热碳化(180～200℃,8～12 h),取部分处理液直接烘干得到I-ACPs;其余处理液经硫酸处理数小时,清洗,离心,55℃烘干便得到Ⅱ-ACPs;将Ⅰ-ACPs和Ⅱ-ACPs均匀分散于超纯水中,添加丁苯酞,常温下180 r/m振荡5 h,离心烘干便得到Ⅰ-ACPs@NBP和Ⅱ-ACPs@NBP.Ⅰ-ACPs@NBP和Ⅱ-ACPs@NBP制备成功,包埋效果好,且具有良好的两亲性和缓释性.Ⅰ-ACPs@NBP的包埋率和缓释性要略优于Ⅱ-ACPs@NBP.Ⅰ-ACPs@NBP和Ⅱ-ACPs@NBP可添加于水凝胶等医用敷料促进伤口愈合.