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Bacillus coagulans is a spore-producing lactic acid bacterium with strong stress resistance. It has been widely used in food preservation, food fermentation, livestock diarrhea prevention, medication-assisted treatment, pollutant removal et al. In the study, a Bacillus coagulans strain with superior inhibition on Staphylococcus aureus, Escherichia coli, Vibrio parahaemolyticus and Aeromonas hydrophila was screened. Its medium composition and culture conditions were optimized in flasks using single factor experiment, Plackett Burman experiment, minimum addition experiment and response surface analysis experiment. The optimal medium composition was determined to be 14.64 g/L molasses, 0.4848 g/L MgSO₄, 0.0833 g/L MnSO₄, 1.5 g/L K₂HPO₄, 0.5 g/L KCl, 8 g/L peptone, and 10 g/L corn syrup dry powder. The optimal culture conditions were 40 °C, initial pH 6.0, inoculation ratio 4%, loading ratio 30%, and rotational speed 140 rpm, and cultivate for 44 h. After feed strategy optimization in 10 L fermenting tank, the concentrations of live bacteria and spores reached 4.63 × 10⁹ CFU/mL and 4.03 × 10⁹ CFU/mL, corresponding to a 14.5-fold and 16.4-fold increase, respectively. This study reduced the production cost of Bacillus coagulans greatly and supply technical support for Bacillus coagulans production.

The considerable contribution of ruminant livestock to methane emissions has become a major global concern in recent years. Although dietary approaches for reducing ruminant methane emissions have been explored, the sustainable potential of probiotics to influence rumen function and lower methane production has increasingly attracted research attention. While previous studies have focused on single or dual-strain probiotics, this study is among the first to evaluate the synergistic effects of quadric-strain formulations. Hence, this study aimed to evaluate the impact of multi-strain probiotic blends, each at two distinct concentrations on rumen fermentation, nutrient degradability, and methane emission in sheep using an in vitro gas production technique following a completely randomized design. The basal diet with no probiotic supplements served as a control, while the supplemented bacterial combinations were Bacillus licheniformis, Lactobacillus acidophilus, L. bulgaricus, and Bifidobacterium bifidum (ABLB; at a ratio of 1:1:1:1) at levels of 2 × 10⁹ (ABLB2) and 4 × 10⁹ (ABLB4) CFU/g of feed, and Lactobacillus casei, Lactobacillus plantarum, Bacillus subtilis plus Bifidobacterium bifidum (CPSB; at a ratio of 1:1:1:1) at levels of 2 × 10⁹ (CPSB2) and 4 × 10⁹ (CPSB4) CFU/g of feed. Probiotic supplementation significantly improved in vitro dry matter and fiber degradability (IVDMD and IVCFD), with the most effective results observed in ABLB treatments. These blends also reduced methane production and ammonia-N concentrations, while increasing total volatile fatty acids (TVFA), indicating more efficient fermentation. Protozoa counts were notably lower in treated groups, supporting the role of probiotics in mitigating methane via microbial modulation (P < 0.01). Probiotic supplementation did not affect the values of pH (P > 0.05). Predictive values for metabolizable energy (ME), net energy for lactation (NEL), and organic matter digestibility (OMD) were improved across treatments. These findings highlight the potential of targeted probiotic formulations to enhance rumen efficiency and reduce environmental emissions in ruminant systems.

Agarwood, a traditional Chinese medicine, has been widely used in the treatment of gastrointestinal diseases. The antibacterial and antioxidant properties of agarwood essential oils (EOs) have been well documented. High-altitude (> 2500 m) regions attract tens of millions of visitors worldwide each year; however, the hypoxic environment poses a threat to the health of the body's organ systems, including the digestive system. Additionally, hypoxia has been reported to alter the gut microbiota and metabolites. Our previous study demonstrated that hypoxia exposure triggered ferroptosis in the gastric and small intestinal mucosa. This study aimed to explore the therapeutic effects and potential mechanisms of EOs in hypoxia-induced gastric and small intestinal mucosal injury. EO effects were evaluated based on clinical manifestations, histopathological assessments, and lipid peroxidation as determined by reactive oxygen species (ROS) and 4-hydroxynonenal (4-HNE) levels. We also assessed microbiota changes through 16 S rRNA gene amplicon sequencing and analyzed metabolites using untargeted liquid chromatography-mass spectrometry in the gastric and small intestinal contents of mice. EO treatment significantly alleviated hypoxia-triggered mucosal damage in the stomach and small intestine. Notably, EOs reduced hypoxia-induced lipid peroxidation and partially recovered the microbiota and metabolite disruptions induced by hypoxia. Specifically, Candidatus_Saccharimonas and Akkermansia may contribute to mucosal repair via regulating xanthoxic acid and aspartylglycosamine, and guanosine, respectively. EOs may provide a promising approach for treating hypoxia-induced gastric and small intestinal damage by repressing lipid peroxidation and regulating the microbiota and metabolites.

Medicinal plants have been used for centuries in traditional practices to treat a wide range of ailments, including viral infections. Phytochemicals found in these plants represent a promising and largely untapped resource for the development of novel antiviral agents, particularly in light of the limited availability of effective antiviral therapies. This study aimed to evaluate the antiviral potential of five polyphenolic compounds commonly found in medicinal plants: quercetin, rutin, baicalein, (-)-epicatechin, and ethyl gallate against bovine alphaherpesvirus type 1 (BoAHV-1), used as a model for the Orthoherpesviridae family. The cytotoxicity and antiviral activity of the compounds were assessed in vitro using the colorimetric MTT assay. Antiviral effects were quantified based on the concentration required to inhibit 50% of viral replication (IC₅₀). Compounds were tested individually and in combination, with treatments applied before, during, and after viral infection. Expression of the viral gB gene was evaluated using RT-qPCR. Quercetin, rutin, and baicalein exhibited notable antiviral activity, with IC₅₀ values of 16.8 µg mL⁻¹, 21.4 µg mL⁻¹, and 26.4 µg mL⁻¹, respectively, and high selectivity indices (> 15.4, 10.0, and 8.0). In contrast, (-)-epicatechin and ethyl gallate showed no measurable antiviral effect (IC₅₀ > 256 µg mL⁻¹). Combinatorial treatments revealed significant synergistic effects. All active compounds reduced gB gene expression, regardless of the timing of treatment. The results support the antiviral potential of certain plant-derived polyphenols, both alone and in synergy, underscoring their promise as candidates for the development of novel antiviral therapies targeting herpesviruses.

One of the major global concerns in human and veterinary medicine at present is the antimicrobial resistance to conventional antibiotics. Natural products from microbial sources appear to be the most favorable alternative to current antibiotics. Biosurfactants (BSs) are surface-active compounds synthesised by a wide variety of microorganisms. Fengycin is an important member of the lipopeptide family, with a wide range of applications in different industries and a broad spectrum of antimicrobial activity against pathogenic microbes. The production of fengycin has been detected in various strains of Bacillus spp., but to our knowledge, not in Heyndrickxia coagulans. Strain H. coagulans (formerly known as B. coagulans) Biocenol™ 9FT27 CCM 9014, which exhibited surfactant activity as assessed by oil spreading assay, was characterised using the 16S rRNA sequencing method. PCR screening detected the presence of fenD, indicating the production of the lipopeptide biosurfactant fengycin. The results of UHPLC-DAD, NMR and MALDI-TOF/MS analysis confirmed the production of fengycin by H. coagulans 9FT27. BS was found to significantly (P < 0.0001) inhibit the biofilm formation of Staphylococcus aureus CCM 4223 and MRSA (methicillin-resistant Staphylococcus aureus) at concentrations ranging from 15 to 0.2 mg/mL. Analysis of qRT-PCR results revealed reduced expression of the srtA, gyrB, clfB and icaADB operon genes, which are associated with biofilm formation. Our results indicate the potential of fengycin in the control of biofilm-related infections, especially those caused by antibiotic-resistant S. aureus strains.

Paddy straw, though abundantly available in India, is often burnt in fields, despite its potential as valuable feed resource for livestock. Ensiling provides a practical solution for its utilization, but challenges like low moisture, high fibre content, and unfavourable climatic conditions limit its effectiveness. In recent times, microbial-based approaches, particularly involving lactic acid bacteria (LAB), have shown promise in improving silage quality. However, suitable thermotolerant LAB strains that can perform under Indian field conditions remain unexplored. To address this, 45 Gram-positive, catalase-negative, and vancomycin-resistant LAB were isolated from naturally fermented silage collected from hot and humid regions of the country. Genus-specific 16S rRNA PCR confirmed all isolates as Lactobacilli and out of these, 35 were acid-tolerant, 26 bile-tolerant, and 12 could grow at 47-50 °C. RSB7 showed the maximum growth at elevated temperatures. Among thermotolerant cultures, six each were identified as homofermentative and heterofermentative, and were preserved in the National Collection of Dairy Cultures. RSB13 showed the highest hydrophobicity. RSB2 had superior co-aggregation and antioxidant activity, while RSB9 exhibited strong autoaggregation, ferulic acid esterase activity, and in vitro straw degradability. All isolates were non-hemolytic, non-mucinolytic, and antibiotic-sensitive. These thermotolerant Lactobacillus spp. showed good potential as safe and functional silage inoculants suitable for tropical Indian conditions.

Defective green coffee beans contain bioactive compounds like chlorogenic acid (CGA) and trigonelline, but high caffeine limits applications. For cost-effective, high-purity industrial use of functional ingredients, this study extracted and purified CGA and trigonelline from low-grade green coffee beans using bacterial enzyme and open column chromatography. Steam pretreatment enhanced the CGA content reaching 35 g/kg of dry weight. Among six strains, Bacillus amyloliquefaciens NY124 was selected for its superior CGA and trigonelline extraction. Its enzyme, a 42 kDa protease, was purified and confirmed by SDS-PAGE and zymography. CGA production doubled with 1.88 U/mL NY124 protease, 7.87% (w/v) green coffee, and 6.85 h via response surface methodology. Diaion HP-20 resins removed 89% of caffeine while silica column chromatography yielded caffeine-free CGA, and trigonelline both achieving high (> 95%) purity. The decaffeinated isolate (Decaf), comprising CGA and trigonelline, exhibited greater functional activity than either fraction alone, highlighting their synergistic effect. Decaf exhibited tenfold higher antioxidant activity than control, along with 52.97% α-glucosidase inhibition (five-fold over control). Decaf isolate demonstrated anti-obesity effects by significantly reducing lipid accumulation by 37% and enhancing lipolysis, evidenced by an 89% increase in free glycerol release compared to the non-treated 3T3-L1 adipocytes.

Bacteriophage receptor binding proteins (RBPs) belong to a group of proteins that are components of the bacteriophage tail. RBPs are mainly responsible for recognizing receptors on the bacterial host surface and enabling infection and subsequent progeny phage multiplication. Our previous research suggested that recombinant tail fiber gp17 (TFPgp17) protein from Yersinia enterocolitica phage φYeO3-12 recognizes serotype O:3 with high specificity and could be used as a diagnostic tool. In this paper, we study the possibility of using modified TFPgp17 in fusion with IgG1 Fc immunoglobulin fragment (Fc_TFPgp17) to improve the efficacy of pathogen recognition by phagocytic cells, opsonization of bacterial cells, and then phagocytosis by the THP-1 macrophages and the HL-60 neutrophils. We demonstrate that the Fc_TFPgp17 protein can bind both bacterial and phagocytic cells, due to the presence of the RBP domain and the IgG1 Fc fragment, respectively. Additionally, it contributes to the better recognition of bacterial cells and their subsequent phagocytosis by phagocytes. Additionally, we proved that glycosylation of Fc_TFPgp17 which occurred during protein production, harms the ability to recognize Y. enterocolitica O:3. Fc_TFPgp17 is a bispecific protein that possesses two biological functions: (I) recognized Y. enterocolitica O:3 cells via phage RBP (TFPgp17) and (II) recognized phagocytic cells via Fc-fragment IgG1 immunoglobulin. In this work, we demonstrated that the recombined bispecific protein facilitates more effective recognition and opsonization of the pathogenic bacterial cell, leading to its subsequent phagocytosis.

To ensure quality stability of strong-flavor Daqu (SFD)-a key saccharification starter in Baijiu production-this study investigated the dynamic succession of fungal communities during fermentation and storage. Using high-throughput sequencing of samples from two production regions, we characterized changes in fungal communities and Physiochemical properties. Predominant genera included Clavispora, Wickerhamomyces, Dipodascus, Thermomyces, Candida, Geotrichum, Aspergillus, and Thermoascus. Correlation analysis revealed significant associations (P < 0.05) between saccharification power and six genera (e.g., Rhizopus and Blastobotrys), and between liquefaction power and four genera (e.g., Millerozyma and Lichtheimia). This study elucidates the dynamic succession of the fungal community during the fermentation and storage of SFD, clarifying the relationship between the fungal community and physicochemical properties.