Renewable lignocellulosic biomass serves as an ideal alternative to fossil resources. However, various inhibitors in its hydrolysate hinder the microbes, mainly because of oxidative stress. In this work, redox-sensitive genetic circuits were constructed in Saccharomyces cerevisiae, Escherichia coli, and Zymomonas mobilis by coupling redoxsensitive promoters to resistance genes, greatly dynamically enhancing stress tolerance. The responsiveness of sensory modules to various inhibitors were assessed. In S. cerevisiae, Yap1-regulated promoters were screened to construct high-tolerance strains, among which the dual-resistance circuit strain showed 24.3%, 31.0%, and 41.7% increases in growth rate, glucose consumption, and ethanol production under combined stress. In prokaryotes, the SoxRS regulon was characterized, with recombinant E. coli exhibiting a 53.0% biomass increase. A distinct SoxRS-like system and native redox-sensitive promoters were identified in Z. mobilis. This work provides insights for designing feedback circuits to dynamically boost microbial stress tolerance.

Pichia kudriavzevii tolerance mechanisms are not well understood, even though strong-flavor Baijiu fermentation places a heavy burden on yeast metabolism due to the accumulation of lactic acid (LA). This study utilized growth kinetics, electron mi-croscopy, antioxidant tests, and integrated metabolomic-transcriptomic studies to an-alyze strain Y2-1, which was isolated from Baijiu pit yellow water. Y2-1 showed a de-layed biphasic growth pattern and could withstand up to 80 g/L of LA. It appears that morphological adaptation plays a role in stress resistance, as scanning electron mi-croscopy showed that cells elongated significantly at high LA levels. Enrichment in pyruvate metabolism, glutathione metabolism, and ABC transporter pathways was among the 1,125 differentially expressed genes and 817 different metabolites found using multi-omics analysis. In order to maintain membrane integrity, ergosterol homeo-stasis, and mitochondrial function, mechanistically speaking, LA tolerance entailed three strategies: (i) activating pyruvate metabolism, which channeled lactate into energy metabolism and mitigated proton imbalance; (ii) enhancing the glutathione antioxidant system, which included spermidine synthase upregulation and improved ROS scavenging and intracellular pH buffering; and (iii) induction of ABC transporters (SNQ2, ABCB7). Molecular insights into yeast acid tolerance and a foundation for creating robust strains to boost Baijiu fermentation efficiency are offered by these findings, which indicate a metabolic-transport-linked defense strategy.

This study investigated Liparis nervosa, an Orchidaceae medicinal plant, to systematically optimize its fermentation process using microbial fermentation technology and to evaluate its therapeutic potential against ulcerative colitis (UC). Based on single-factor experiments and orthogonal design, total antioxidant capacity was used as the primary evaluation index, and the optimal fermentation conditions were determined as follows: 1% aqueous extract concentration, fermentation temperature of 35 °C, and fermentation time of 4 days. Under these conditions, the antioxidant activity of the fermented product was significantly enhanced, accompanied by increased flavonoid content and hydroxyl radical scavenging capacity, while total phenolic content decreased, suggesting that fermentation promotes structural transformation and functional optimization of bioactive components. In a dextran sulfate sodium (DSS)-induced mouse model of UC, fermented Liparis nervosa extract significantly improved general physiological conditions, reduced the disease activity index (DAI), and alleviated colon shortening and tissue damage. At the molecular level, fermented Liparis nervosa downregulated pro-inflammatory cytokines, including TNF-α, IL-6, and NF-κB, while upregulating intestinal barrier-related proteins such as ZO-1, Claudin-1, and Mucin-2, thereby promoting mucosal repair. In conclusion, optimized fermentation enhances the antioxidant and anti-inflammatory activities of Liparis nervosa, enabling it to ameliorate UC through multiple mechanisms, including inflammation suppression, intestinal barrier restoration, and modulation of gut microbiota. This study provides a theoretical and experimental basis for the development of Liparis nervosa-based functional foods and traditional Chinese medicinal preparations.

In this study, high-temperature blackening (pile fermentation), a technique originally used for dark tea processing, was applied for the first time to the processing of goji berries (Lycium barbarum L.) to enhance their functional components and antioxidant activity. Single factor experiments were conducted to examine the effects of blackening temperature (60–80 °C), time (40–60 h) and water replenishment (25–45 %) on total phenolic content, flavonoid content, reducing sugar content, DPPH radical scavenging capacity and sensory quality. On this basis, a three factor, three level Box Behnken response surface design was employed to optimize the process, using DPPH radical scavenging capacity as the response value. The results showed that temperature was the dominant factor affecting the quality of blackened goji berries, with the order of influence strength being temperature > water replenishment > time. The established quadratic regression model was significant (P = 0.0011) with a coefficient of determination R² = 0.9473. The optimal process parameters were determined as follows: dried goji berries with a moisture content of 10–13 % were selected, cleaned, supplemented with water to 35 %, and then blackened at 72 °C for 50 h. Under these optimized conditions, the DPPH radical scavenging capacity reached 21.7 μmol/mL, while total phenolic and flavonoid contents remained high, and the sensory evaluation was excellent. This study provides a scientific basis and an industrially applicable technical solution for the high value processing of goji berries.

To address production challenges in tea processing, freeze-withering was introduced for yellow tea. This study conducted a comprehensive assessment of the sensory quality, volatile compounds and metabolomics characteristics of freeze-withering yellow tea (FYT) and unfrozen withered yellow tea (UYT). The results indicated that the FYT samples contained higher levels of volatile compounds, including (E,E)-3,5-octadien-2-one, 1-octanol, linalool, beta-myrcene, 2,6-dimethyl-3,7-octadiene-2,6-diol, 2-pentylfuran, and phenylethyl alcohol, compared to UYT. Consequently, FYT exhibited more pronounced sweet, woody, and baked aromas. A total of 15 aroma compounds from the two tea samples were identified as key components and integrated into the flavor wheel model. The enhancement of umami, sweetness, and richness in yellow tea was attributed to increased levels of metabolites, including p-Coumaroyl quinic acid, D-Gluconic Acid, Theaflavin 3,3 '-digallate, Theaflavin-3-gallate, Theaflavin, and 9S,12R,13S-Trihydroxy-10E,15Z-octadecadienoic acid. Conversely, the reduction in bitterness was linked to decreased levels of compounds such as Epigallocatechin 3,4 '-di-O-gallate, (-)-gallocatechin gallate, (-)-catechin gallate, and Procyanidin B3. In addition, after freeze-withering, the content of theaflavins in yellow tea increased significantly. In conclusion, the freeze-withering process is demonstrated to enhance the quality of yellow tea, and it provides a one-month buffer period for tea processing, thereby providing a theoretical basis for alleviating the processing pressure of tea in spring.

BACKGROUND:Streptococcus suis (S. suis) is a significant zoonotic pathogen, with serotype 2 (SS2) being the most prevalent. Suilysin (SLY), an essential toxin indicator for S. suis, is crucial in the infections caused by SS2. Consequently, an anti-virulence strategy targeting SLY presents a promising approach to combat SS2. OBJECTIVES:To investigate the effect of curcumin, a naturally occurring phenolic compound, on the hemolytic activity of SLY and the pathogenicity of SS2, and to assess its viability as a novel anti-virulence candidate for addressing SS2 infections. METHODS:The antibacterial activity of curcumin against SS2 was assessed by determining its minimal inhibitory concentration (MIC) and monitoring bacterial growth curves. Its impact on hemolytic activity was tested using supernatants from SS2 cultures and purified recombinant SLY protein. Western blot was used to determine if curcumin affected the secretion level of SLY. The interaction between curcumin and SLY was predicted using molecular docking. Finally, the protective efficacy of curcumin was evaluated in a murine model of lethal SS2 infection. RESULTS:Curcumin (<1,024 μg/mL) did not inhibit SS2 growth or viability. However, it significantly and dose-dependently inhibited the hemolytic activity of both SS2 culture supernatants and purified SLY. Molecular docking predictions indicated that curcumin engaged three domains of SLY (D1, D2 and D3) simultaneously, forming five hydrogen bonds with residues ASN-50, GLN-107 and LYS-190, thereby supporting its multidomain-binding capability. Furthermore, curcumin administration significantly reduced the mortality of SS2-infected mice in vivo. CONCLUSION:Substantial evidence is presented demonstrating that the pathogenicity of SS2 can be effectively attenuated by curcumin via inhibition of the hemolytic activity of SLY, which supports the potential utility of curcumin as a host-directed anti-virulence agent for SS2 infections.

As the primary raw material for Baijiu brewing, sorghum variety exerts an intricate influence on the taste profile of strong-flavor Baijiu. However, how sorghum variety comprehensively affects Baijiu flavor formation through fermentation by microorganisms and metabolites remains largely unknown. Using 16S&ITS rRNA gene sequencing and non-targeted metabolomics, in this study we comprehensively analyzed the changes in microbial communities and metabolites during fermentation of a glutinous and non-glutinous sorghum variety. The results showed that these varieties significantly affected microbial diversity and community structure, and their interactions, among which, there were particularly complex interactions among bacterial communities, while the effects of “functional differentiation” and “community aggregation” of fungal communities were prominent. Furthermore, three bacterial and nine fungal genera were identified as core microorganisms related to changes in glycerophospholipids during fermentation, that led to a change in ester content, ultimately improving Baijiu quality. These findings provide reference for the selection of brewing materials.

Immobilized lipases have received great attention in food, environment, medicine, and other fields due to their easy separation, high stability (temperature, pH), and high storage properties. After immobilization, lipase transforms from a homogeneous to a heterogeneous state, making it easier to recover from the reaction substrate and achieve recycling, which is in line with the concept of green chemistry and reduces protein contamination in the product. There are various materials for enzyme immobilization, including polysaccharides from natural sources, inorganic compounds, carbon nanotubes, metal-organic framework materials, and so forth. Magnetic immobilization carriers have been widely studied due to their ability to achieve separation by adding a magnetic field. Its immobilization method can be simply divided into two categories: physical action (adsorption, embedding) and chemical binding (covalent, cross-linking). Some studies mainly discuss the immobilization support materials, immobilization methods, and applications of immobilized lipases in food. On this basis, our review also focuses on the changes in crosslinking agents for immobilized lipases, different methods to promote immobilization, new trends in the study of immobilized lipases, and proposes prospects for immobilized lipase research in the food industry.

Chinese distilled liquor, known as Baijiu , typically has a relatively high ethanol content (52 or 53% alcohol by volume, ABV) and is characterized by a powerful, heady scent. When its alcohol content is less than 45% ABV, Baijiu loses its flavor and becomes cloudy and tasteless; thus, it is relatively bland and thin. Since this phenomenon has not been reasonably explained, the aim of this study is to determine its underlying mechanism by examining the droplet evaporation. A 1.0 µL of droplets were applied to the substrate surface for evaporation. The results revealed that a reduction in the alcohol content (<45% ABV) triggered the self‐assembly of unique long‐chain fatty acid ethyl esters into various nano‐ or microparticles with sizes ranging from 100 nm to 10 µm within the Baijiu droplets. These particles deposit under the influence of internal flow and exhibit Baijiu ‐specific coffee‐ring effects after drying. Interestingly, these particles encapsulated the water‐soluble or insoluble flavor chemicals, resulting in the brightness and aroma/flavor of Baijiu decreased radically; this is the reason that a high alcohol content is needed in Baijiu . These findings offer new insights for the quality control of low‐alcohol Baijiu and Baijiu identification.

Traditional sludge management methods are energy and cost intensive. This study evaluated the filamentous cyanobacterium Pseudoscillatoria coralii BERC01 to remove sludge from wastewater while simultaneously producing biomass for clean energy. P. coralii BERC01 removed 99.99 % of the sludge and reduced other pollutants by 45-86 % within three days. The biomass was rich in carbon and hydrogen, with a high heating value of 21.60 MJ/kg, highlighting its potential as a feedstock for clean energy. The biomass was pyrolyzed at heating rates of 10-50 degrees C/min. The transformation demonstrated high energy efficiency, characterized by higher transformation efficiency (76-79 %), reduced activation energy (192-196 kJ/mol), and a lower energy barrier (similar to 4 kJ/mol) between activation energy and enthalpy values. The pyrolysis products primarily consisted of aliphatic compounds, ketones, esters, alkyl halides, and phenols. Additionally, an artificial neural network regression model was trained on MLP data to compute activation energy values, which closely aligned with pyrolysis data interpretations (R-2 > 0.988). The M-DAEM model also accurately fitted the experimental data (R-2 > 0.993), further validating the pyrolysis results. This research underscores the integration of cyanobacteria-based wastewater treatment with pyrolysis as a sustainable sludge management strategy, paving the way for carbon-neutral resource recovery and energy production.

Introduction:Pichia kudriavzevii is a prevalent non-Saccharomyces cerevisiae yeast in baijiu brewing. The aim of this study was to isolate a high temperature resistant Pichia kudriavzevii strain from the daqu of strong flavor baijiu and to elucidate its molecular mechanism. Methods:Growth activity was assessed at temperatures of 37°C, 40°C, 45°C, and 50°C. Morphological changes were observed by scanning electron microscopy at 37°C, 45°C, and 50°C. Subsequent analysis of the transcriptomics and metabolomics was undertaken to elucidate the molecular mechanism of heat tolerance. Results:The strain was able to tolerate high temperature of 50°C, undergoing substantial morphological alterations. Gene ontology (GO) analysis of the transcriptomics revealed that differentially expressed genes (DEGs) were enriched in pathways such as ATP biosynthesis process and mitochondrion; Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis showed that DEGs were up regulated in oxidative phosphorylation. Utilising liquid chromatograph-mass spectrometer, a total of 463 cationic differential metabolites and 352 anionic differential metabolites were detected and screened for differential substances that were closely related to heat tolerance (NAD+ and ADP); KEGG analysis showed that metabolites were up regulated in purine metabolism. Furthermore, correlation analyses of transcriptomics-metabolomics demonstrated a strong positive correlation between the metabolites NAD+ and ADP, and multiple DEGs of the oxidative phosphorylation pathway. Discussion:These results suggest that the heat tolerant strain can be able to counteract high temperature environment by up regulating energy metabolism (especially oxidative phosphorylation) to increase ATP production.

Sorghum is crucial in Baijiu brewing. Previous studies have shown that glutinous sorghum (LS) and non-glutinous sorghum (FS) significantly affect Zaopei's lipid metabolism and lipids affect flavor perception. This study aimed to explore the quality differences in Baijiu brewed with different sorghum varieties and the effects of lipids. Sensory evaluation, volatilomics, and lipidomics were used to analyze differences in flavors and lipids. The results showed that significant differences in flavor existed between the two types of Baijiu. The aged flavor of LS was more pronounced and its mouthfeel was smoother. However, the FS showed a more intense aroma release. In addition, FA 18:1;O3 (fatty acyls), acetaldehyde, and ethyl caprylate contributed to the smoothness and softness of Baijiu. These results suggest that the lipid composition of Baijiu affects its aroma and taste, thus providing a reference basis for selecting suitable raw sorghum materials to enhance the quality of Baijiu.

Constipation, a widespread gastrointestinal disorder, imposes significant burdens on healthcare systems the and global health-related quality of life, yet current options remain suboptimal due to limited mechanistic understanding and efficacy limitations. Given the pivotal significance of the interactions between the gut microbiota and the host on governing bowel movement, we employed a multi-modal approach integrating animal experiments, ELISA, histopathology, qRT-PCR, GC-MS, and 16S rRNA metagenomics to evaluate the functional potential of Lactobacillus rhamnosus LRa05 against loperamide-induced constipation in mice. LRa05 treatment markedly alleviated constipation symptoms, as evidenced by reduced first black stool expulsion time, increased fecal moisture, and enhanced intestinal motility. Mechanistic investigations revealed that LRa05 balanced gastrointestinal regulatory peptides. It also downregulated aquaporin (AQP4/AQP8) mRNA levels and activated the SCF/C-Kit signaling pathway. These effects contributed to the restoration of intestinal peristalsis. Furthermore, LRa05 rebalanced gut microbiota composition by enriching beneficial, including Alloprevotella and Lachnospiraceae NK4A136, key SCFA producers. Thus, LRa05 could boost short chain fatty acid (SCFA) production, which is vital for stimulating intestinal motility, improving mucosal function, and relieving constipation. These findings demonstrated that LRa05 could mitigate constipation through a multi-target mechanism: regulating motility-related gene transcription, restructuring the microbial community, balancing gastrointestinal peptides, repairing the colonic mucosa, and promoting SCFAs for fecal hydration. Our study positions LRa05 as a promising probiotic candidate for constipation management.

Commercial cultivation of Spirulina relies on expensive chemicals. This study aimed to optimize low-cost cultivation media for upscaling of the Spirulina cultivation for food applications. Here, low-cost nitrogen source resulted in 3 gL- 1 of biomass while outdoor pilot-scale cultivation produced 6.5-9.6 g m- 2day- 1 of biomass. The growth media prepared in underground water (UGW) using commercial-grade chemicals (UGW + CC) was found to be the most suitable low-cost alternative media which produced 2.3 +/- 0.28 gL- 1 of biomass containing 56 +/- 1.22 % proteins, 22 +/- 1.88 % carbohydrates, and 12 +/- 2.52 % lipids. GC-MS-based metabolomic analysis implied that only four metabolites were either down or upregulated out of 50 detected metabolites. The Hep G2 cancer cell line-based study showed 15-fold higher free radical scavenging activity in UGW + CC grown cells compared to control. This study provides a basis for process optimization towards commercial-scale cultivation of Spirulina using small and medium enterprise mode.

Spirulina platensis (S. platensis) produces a variety of biologically active compounds that exhibit antioxidative, anti-inflammatory, antibacterial, and immunoregulatory properties. Here, dextran sulfate sodium (DSS) was used to develop an animal model of ulcerative colitis (UC) to evaluate the potential protective benefits of fermented S. platensis against DSS-induced colitis in mice. Gut microbiota alterations were investigated using 16S ribosomal RNA (rRNA) gene sequencing. Real-Time Quantitative PCR (RT-qPCR) was used to detect the expression of mRNA of inflammatory factors and pathway-related molecules in the inflammatory process. The results showed that fermented S. platensis could reverse the DSS-induced weight loss and colon length shortening in mice. The study of the 16S rRNA sequence showed that treatment with fermented S. platensis changed the gut microbiota of mice, with an increase in the relative abundance of beneficial bacteria such as Lachnospira. According to RT-qPCR and histopathological analyses, fermented S. platensis also improved the loss of goblet cells and neutrophil infiltration induced by DSS, while improving anti-inflammatory capacity. In addition, compared with the model group, the fermentation group significantly downregulated the relative expression of MyD88/TLR4 signaling pathway genes compared with the nonfermentation group. Overall, this investigation demonstrated that fermentative S. platensis can reduce DSS-induced UC by regulating gut microbiota composition, and the MyD88/TLR4 signaling pathway.

IntroductionEchinococcus granulosus, known as cystic echinococcosis, is a prominent zoonotic parasitic disease of significant global concern. The definitive hosts serves as the primary reservoir for the transmission of echinococcosis, as well as a main factor in the prevention and control of the disease. Unfortunately, there is currently no commercially available vaccine for these hosts. Nevertheless, DNA vaccines show potential as a feasible strategy for the control and management of parasitic diseases.MethodsIn this study, the EgM123 antigen was selected for its well-documented immunogenic properties to develop a DNA vaccine aimed at combating E. granulosus infection in canines.ResultsThe results showed a marked increase in IgG levels in the group vaccinated with pVAX1-EgM123 DNA compared to the PBS group. Additionally, the cytokines IL-1, IFN-γ, IL-4, and IL-6 were significantly upregulated in the pVAX1-EgM123 DNA vaccine group. Furthermore, in comparison to the PBS control group, the EgM123 DNA vaccine group exhibited a notable 87.85% reduction in worm burden and a 65.00% inhibition in segment development.DiscussionThese findings indicate that the pVAX1-EgM123 DNA vaccine shows promising immunogenicity, successfully eliciting a targeted immune response in canines. Moreover, it significantly diminishes the worm burden and hinders the progression of tapeworms in the pVAX1-EgM123 DNA vaccine group. These findings suggest that the pVAX1-EgM123 DNA vaccine holds promise as a potential candidate vaccine for combating E. granulosus infection in dogs.

Tibetan tea changes during microorganism fermentation. Research on microorganisms in Tibetan tea has focused on their identification, while studies on the influence of specific microorganisms on the components and health functions of Tibetan tea are lacking. Bacillus licheniformis was inoculated into Tibetan tea for intensive fermentation, and the components of B. licheniformis-fermented tea (BLT) were detected by liquid chromatography with tandem mass spectrometry (UHPLC-TOF-MS), and then the effects of BLT on intestinal probiotic functions were investigated by experiments on mice. The results revealed the metabolites of BLT include polyphenols, alkaloids, terpenoids, amino acids, and lipids. Intensified fermentation also improved the antioxidant capacity in vivo and the protective effect on the intestinal barrier of Tibetan tea. In addition, the enhanced fermentation of Tibetan tea exerted intestinal probiotic effects by modulating the relative abundance of short-chain fatty acid-producing bacteria in the intestinal flora. Therefore, intensive fermentation with B. licheniformis can improve the health benefits of Tibetan tea.