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Formononetin is a natural flavonoid existing widely in plants with many pharmacological effects. However, its application is limited by structure, poor water solubility and low bioavailability. In this study, Bacillus velezensis LQ5 was isolated from the inter-root soil of Glycyrrhiza uralensis Fisch for the first time and formononetin was firstly structurally modified by whole-cell catalysis of LQ5 to obtain formononetin-7-O-β-D-glucoside (FG), formononetin-7-O-β-(6''-O-succinyl)-D-glucoside (FGS) and formononetin-7-O-phosphate (FP). The selective preparation of the three products was achieved by adjusting the content of yeast extract, type and content of sugars, metal ions, pH and ATP content. The result confirmed that FP had the ideal drug-likeness properties and showed a greater ability to reduce intracellular reactive oxygen species levels and regulate oxidative enzymes. This work successfully established a biotransformation method for the efficient transformation of formononetin to produce high-value formononetin derivatives. [Display omitted] • Bacillus velezensis was firstly screened for the efficient biotransformation of formononetin. • Three rare formononetin derivatives were highly produced by LQ5. • Among products, formononetin-7-O-phosphate showed the ideal drug-likeness properties. • Formononetin-7-O-phosphate has good neuroprotective activity with low toxicity. [ABSTRACT FROM AUTHOR]

This study aimed to isolate, purify, and characterize a lipase from the gut symbiont Bacillus megaterium F25 (GenBank accession: MF597792) of the aquatic insect Rhantus suturalis, with a focus on its potential applications in biodiesel and food industries. Under optimized culture conditions, B. megaterium F25 could produce 583 U/L of lipase in shaking flask culture. The purified lipase (PL) exhibited a specific activity with 113.89 U/mg, and its molecular weight was determined as 34 kDa. The activity of PL was enhanced by methanol, ethanol, Tween‐80, Triton X‐100, Ca2+, and Mg2+, while β‐mercaptoethanol, EDTA, SDS, Fe2+, Mn2+, and Cu2+ were inhibitory. PL showed optimal activity and stability at neutral and slightly acidic pHs, as well as in a temperature range of 20°C–30°C. PL displayed strong hydrolytic activity toward plant oils and animal fats, indicating its potency for both the food industry and the remediation of oil‐contaminated environments. When tested as a catalyst, PL provided biodiesel production with a transesterification yield of 86.8% under optimized conditions (36 h reaction time, 4 mL enzyme solution, 30°C, pH 7.0, and waste cooking oil:methanol ratio of 10 mL/40 mL). This is the first report on the lipase‐producing potential of gut microbial symbionts of aquatic insects. Furthermore, B. megaterium lipase was tested for the first time as a biocatalyst for biodiesel production. [ABSTRACT FROM AUTHOR]

The fall armyworm, Spodoptera frugiperda is a major pest of maize crops and necessitates effective control measures. Excessive use of chemical pesticides often results in the development of resistant insect populations and environmental contamination, highlighting the need for environmentally friendly substitutes. This research aimed to estimate the potential of maize (COH6) apoplastic fluid bacterium Bacillus amyloliquefaciens (MZ895491), as a biocontrol agent against second instar S. frugiperda larvae under laboratory and pot culture conditions. The results suggest that the presence of B. amyloliquefaciens in the artificial diet could reduce the growth and development of S. frugiperda larvae. Metabolic profiling of extracellular components of B. amyloliquefaciens revealed the presence of numerous defensive and anti-feeding metabolites. A study conducted in pots demonstrated that foliar application of B. amyloliquefaciens to 5 d old maize resulted in a significant increase in antioxidant activity (83.3%), chlorophyll content (63.3%) and phenolic content (81.3%) in the leaves of 35 d old maize after 24 h of S. frugiperda infestation. Feeding bioassay further indicated significant reduction in the feeding capacity of S. frugiperda larvae on maize inoculated with B. amyloliquefaciens. The study observed that a metabolic modification in maize leaves likely led to reduced growth in larvae during the whole plant bioassay. This suggests that foliar application of B. amyloliquefaciens may effectively serve as one of the biocontrol agents against Spodoptera frugiperda. The application appears to alter the feeding behaviour of the larvae and modify maize leaf metabolism. [ABSTRACT FROM AUTHOR]

This study was conducted to identify and characterize the Bacillus strain from Goat's milk in Algeria and to evaluate the prebiotic effect of H. scoparia aqueous extract and ZnO-NPs on the isolated Bacillus strain. Potentially probiotic bacteria were isolated and identified based on phenotypic characteristics, including the morphological, physiological (growth temperature, salt tolerance), biochemical (API 10S strip kits), and confirmed by 16S rDNA gene sequencing. Bacillus pumilus specie of lactic acid bacteria were identified. The base pair length of amplified DNA for the isolate was 1500 Bp. The isolates could not grow at 10°C and 45°C and tolerate up to 6% salt. H. scoparia extract and ZnO-NPs have a beneficial effect on the Bacillus pumilus strain for acid tolerance, bile tolerance, and cell surface hydrophobicity respectively; H. scoparia extract and ZnO-NPs results are high comparing to the control group's results. As the concentration of the tested samples increases, the percentage of probiotic characteristics of Bacillus pumilus increases, in contrast to the control sample. Therefore, they could be useful tools to define adequate combinations in colonic foods development and health benefits. The beneficial physiological and biochemical properties of isolated Bacillus pumilus space from Goat's milk with the H. scoparia aqueous extract and ZnO-NPs revealed their potential applications in the food industry. [ABSTRACT FROM AUTHOR]

Gray sufu is a traditional Chinese fermented soybean curd, and its flavor is significantly influenced by bacterial community. In this study, volatile flavor compounds (VFCs) were examined by headspace solid‐phase microextraction (HS-SPME) in conjunction with gas chromatography and mass spectrometry (GC‐MS). Additionally, bacterial community was analyzed using high-throughput sequencing. The results showed that, a total of 156 VFCs were tentatively identified, in which 8 esters, 6 S/N-containing compounds, 3 alcohols, 3 aldehydes, 1 ketone and 3 other compounds were recognized as the main characteristic VFCs. The abundant S/N-containing compounds are the most important flavor characteristics of gray sufu. A total of 4 phyla and 12 genera were revealed as dominant bacteria. Firmicutes and Proteobacteria were the most abundant phylum, whereas Bacillus, Tetragenococcus and Lactococcus were the prevailing genera. According to the KEGG pathway annotation, amino acid metabolism (26.98%) was the highest metabolic pathway. Among them, aromatic amino acids metabolism accounted for the highest proportion, up to 34.94%. Correlation analysis showed that Lactobacillus, Tetragenococcus, Bacillus, Pseudomonas and Halanaerobium were the top five positive flavor-producing bacteria. The results will be helpful for understanding the fermentation mechanism of gray sufu and improving flavor quality by developing microbial regulation strategies. [ABSTRACT FROM AUTHOR]

Ulcerative colitis (UC) is a condition characterized by inflammation and ulcer formation in the colon and rectum due to genetic and environmental factors. It is a common condition, with a global prevalence rate exceeding 0.3%. Current treatments have limited efficacy and can cause unwanted side effects, leading to a high recurrence rate and reduced quality of life for patients. This study suggests that Bacillus clausii has a beneficial role in reducing intestinal inflammation and relieving colitis symptoms in mice. The study aimed to examine B. clausii's potential to reduce the progression and pathogenesis of dextran sulphate sodium (DSS)–induced UC. Bacillus clausii was administered to mice as a pre‐treatment, post‐treatment and adjunct treatment with sulfasalazine for 14 days. The study found that B. clausii effectively reduced the severity of colitis in mice when used preventatively. Administering B. clausii after the onset of colitis also effectively alleviated symptoms. Combining B. clausii with standard sulfasalazine as adjunct therapy was more effective in reducing intestinal inflammation than using a single therapy alone. B. clausii has shown the potential to prevent colon damage and decrease the likelihood and severity of the disease. Immunohistochemistry results revealed a decrease in the expression of pro‐inflammatory cytokines such as IL‐1β, TNF‐α and NFkB in colon tissue. Additionally, mice that received B. clausii showed a significant increase in anti‐oxidant levels and improved haematological markers. In conclusion, it must be emphasized that B. clausii possesses the potential to alleviate the symptoms of UC. [ABSTRACT FROM AUTHOR]

Anthracnose, caused by Colletotrichum spp., is a threat to strawberry production globally. Unlike their chemical counterparts, microbial biofungicides offer a method of postharvest fungal disease control that is safe, sustainable and less affected by pathogen resistance. The present study evaluated the antifungal effects of three bacteria, Bacillus velezensis strains SH1 and SH2 and Pseudomonas azotoformans strain SH3, obtained from sheep manure compost tea. The bacteria or their cell‐free filtrates were tested against Colletotrichum acutatum and Colletotrichum gloeosporioides in bioassays and against strawberry anthracnose. In addition, precipitated or extracted extracellular fractions were tested to determine the effects on membrane permeability of Colletotrichum spp. spores. Confrontation assay results showed all bacteria inhibited mycelial growth, with B. velezensis SH1 and P. azotoformans SH3 being the most effective. All cell‐free filtrates inhibited mycelial growth with B. velezensis SH1 and SH2 resulting in the highest inhibition. The bacteria suppressed anthracnose lesions on strawberry fruit although effective treatments varied by causal mould. B. velezensis SH1 and SH2 significantly permeabilized spore membranes, indicating antibiosis as a possible mode of action. Investigation into antimicrobial compound production found various homologues of the lipopeptides fengycin, iturin and surfactin were produced by B. velezensis SH1 and SH2. Results suggest that lipopeptides produced by B. velezensis strains permeabilize Colletotrichum cell membranes, and that fengycins were the most inhibitory of the lipopeptides against Colletotrichum spp. [ABSTRACT FROM AUTHOR]

Culicoides oxystoma Kieffer (Diptera: Ceratopogonidae) has been vectoring several arboviruses, protozoa and nematodes, leading to mortality and morbidity of livestock and wild ruminants in the tropics and subtropics. Insight into the bacterial communities associated with the vector species must be worked out. This work tries to inventorize the bacterial communities associated with this important vector species. Acquisition of gut microbiota may be the parental origin, while some are obtained through feeding during larval stages. Culicoides oxystoma possesses semi‐aquatic life cycle strategies for egg‐laying and larval survival. The bacteria associated with C. oxystoma were compared throughout (i) life stages: egg, larval instars, pupa, adult: male and female obtained from laboratory colony; (ii) field‐collected adult: male and age‐graded females; and (iii) natural breeding substrate and artificial rearing substrate. The culture‐dependent bacteria were identified by Sanger sequencing of 16S rRNA, and haemolytic bacteria were screened on blood agar. Results show that Firmicutes and Proteobacteria are the predominant Phyla, of which Bacillus spp. was the most abundant across the life stages. Across the life history, Bacillus cereus, Bacillus pumilus, Bacillus tropicus, Lysinibacillus sp. and Paenibacillus sp. were retrieved routinely. Bacillus cereus and Alcaligenes faecalis were detected in the lab‐reared specimens and shared between the natural breeding site and rearing medium. From the adults trapped across two locations, B. cereus, Bacillus flexus, A. faecalis, Enterococcus faecium and Pseudomonas sp. were isolated. The bacterial species associated with this vector may influence various physiological traits, such as vectorial capacity, digestion and larval development, which need further investigation. [ABSTRACT FROM AUTHOR]

BACKGROUND: Research on the co‐production of multiple enzymes by Bacillus velezensis as a novel species is still a topic that needs to be studied. This study aimed to investigate the fermentation characteristics of B. velezensis D6 co‐producing α‐amylase and protease and to explore their enzymatic properties and applications in fermentation. RESULTS: The maximum co‐production of α‐amylase and protease reached 13.13 ± 0.72 and 2106.63 ± 64.42 U mL−1, respectively, under the optimal fermented conditions (nutrients: 20.0 g L−1 urea, 20.0 g L−1 glucose, 0.7 g L−1 MnCl2; incubation conditions: initial pH 7.0, temperature 41 °C, 8% inoculation size and 30% working volume). Moreover, the genetic co‐expression of α‐amylase and protease increased from 0 to 24 h and then decreased after 36 h at the transcriptional level, which coincided with the growth trend of B. velezensis D6. The optimal reaction temperature of α‐amylase was 55–60 °C, while that of protease was 35–40 °C. The activities of α‐amylase and protease were retained by over 80% after thermal treatment (90 °C, 1 h), which indicated that two enzymes co‐produced by B. velezensis D6 demonstrated excellent thermal stability. Moreover, the two enzymes were stable over a wide pH range (pH 4.0–8.0 for α‐amylase; pH 4.0–9.0 for protease). Finally, the degrees of hydrolysis of corn, rice, sorghum and soybeans by α‐amylase from B. velezensis D6 reached 44.95 ± 2.95%, 57.16 ± 2.75%, 52.53 ± 4.01% and 20.53 ± 2.42%, respectively, suggesting an excellent hydrolysis effect on starchy raw materials. The hydrolysis degrees of mackerel heads and soybeans by protease were 43.93 ± 2.19% and 26.38 ± 1.72%, respectively, which suggested that the protease from B. velezensis D6 preferentially hydrolyzed animal‐based protein. CONCLUSION: This is a systematic study on the co‐production of α‐amylase and protease by B. velezensis D6, which is crucial in widening the understanding of this species co‐producing multi‐enzymes and in exploring its potential application. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

The incidence of brown leaf spot, attributed to Alternaria tenuissima, has exhibited an increase within potato fields in Iran. The economic losses caused by brown leaf spot and detection of cross-resistance among commonly used fungicides have incited research towards identifying alternative biocontrol sources to manage this aggressive pathogen in combination with chemicals. Among bacterial isolates that showed inhibition of A. tenuissima growth, the tested biocontrol properties and plant growth-promoting (PGP) characteristics varied. Three strains with antifungal traits and one strain with PGP capacity were chosen for further in vitro and in vivo experiments. They were identified as Bacillus halotolerans-H14, Bacillus sp.-H52, Serratia polymuthica-FR1, and Stenotrophomonas sp.-J29, respectively, using a combination of phenotypic traits and 16S rRNA sequencing. In co-culturing assays with the aforementioned bacterial strains, it was observed that they induced hyphal structural deformation and suppressed spore germination of A. tenuissima. Monitoring of the disease symptoms showed the ability of H14, FR1, and J29 to decrease disease severity under in vivo challenge experiments. Moreover, the role of aforementioned bacteria was studied in activation of potato defence pathways against A. tenuissima. During Solanum tuberosum-A. tenuissima interaction, biochemical attributes related to defence response such as superoxide and hydrogen peroxide production, redox enzymes (catalase, superoxide dismutase, ascorbate peroxidase, and guaiacol peroxidase), phenylalanine ammonia-lyase activity, and accumulation of total phenolics were markedly increased in potato plants pre-treated with Stenotrophomonas sp.-J29 and Serratia plymuthica-FR and post-inoculated with A. tenuissima. This study provides the initial evidence demonstrating the potential role of Bacillus halotolerans, Serratia plymuthica, and Stenotrophomonas sp. as prohibitor of disease progression as well as biological inducer of resistance in potato—A. tenuissima interplay. [ABSTRACT FROM AUTHOR]

The release of bioactive peptides from proteins can be achieved by enzymatic hydrolysis, whereby mainly commercial enzymes are applied, although increasing attention is focused on alternative proteases. Hence, crude proteases from Bacillus sp. CL14, CL18, and CL33A were investigated to obtain antioxidant hydrolysates from bovine sodium caseinate (NaCAS) and soy protein isolate (SPI). The proteases were able to hydrolyze both substrates. Hydrolysis improved the radical-scavenging, Fe2+-chelating, and reducing power abilities of NaCAS and SPI. Higher antioxidant activities were commonly achieved at 2–3 h of hydrolysis. Overall antioxidant activities were higher for NaCAS hydrolysates produced with CL14 > CL18 > CL33 protease, and for SPI hydrolysates obtained with CL14 > CL33A ∼ CL18 protease. Generation of antioxidant protein hydrolysates suggest applications of enzymes and hydrolysates in food/feed (bio)technology. [ABSTRACT FROM AUTHOR]

The synthesis of pyrazine-2-carboxylic acid hydrazide, a heterocyclic hydrazide compound, with negligible production of the by-product (pyrazine-2-carboxylic acid) in a solvent-free reaction condition was developed using the acyltransferase activity of amidase of Bacillus smithii strain IITR6b2. This study involves a greener approach with no hazardous chemicals and one-step biotransformation of pyrazinamide to its acid hydrazide (through hydrazinolysis). The Central Composite Design of the Response Surface Methodology was used to find the factors affecting the synthesis of the pyrazine-2-carboxylic acid hydrazide and pyrazine-2-carboxylic acid to find its true optimum. The four factors, namely pyrazinamide, hydrazine dihydrochloride, temperature, and cell concentrations, were considered during optimization. The optimized reaction conditions from the Central Composite Design for achieving the 32.26 mM of pyrazine-2-carboxylic acid hydrazide involve 40 mM of pyrazinamide, 1000 mM of hydrazine dihydrochloride with 2.5 mg/mL cell concentration at 20 °C. It resulted in an optimum production of pyrazine-2-carboxylic acid hydrazide utilizing the acyltransferase activity of amidase of Bacillus smithii IITR6b2, and the results obtained through the Design of Experiments were validated. The fed-batch biotransformation was carried out with alginate-entrapped whole-cell enzyme with the following parameters: agitation at 200 rpm, a pyrazinamide concentration of 40 mM, and 1000 mM of hydrazine dihydrochloride. The final pyrazine-2-carboxylic acid hydrazide concentration of 126 mM was obtained, corresponding to a 63% molar conversion. [ABSTRACT FROM AUTHOR]

Fish farming practices currently make effective use of probiotic Bacillus species, specifically Bacillus subtilis and B. licheniformis. The current study assessed the water quality, growth performance, body composition, hemato-biochemical activities, immune regulatory genes, and resistance to Aspergillus flavus in order to determine the effectiveness of the water additive probiotic Bacillus species mixture (SANOLIFE®PRO-W) on Nile tilapia aquaculture. Fish were kept in four groups (control, 0.01, 0.02, 0.03) gm. /m3for 56 days using Bacillus species in-water treatment. The results showed that the fish treated with SANOLIFE® performed significantly better (P < 0.05) in terms of growth. Significant (P < 0.05) improvements were also observed in the immune regulatory genes, antioxidant capacity, and haemato-biochemical parameters. A. flavus challenged fish showed significantly (P < 0.05) lower mortalities, indicating that Bacillus species probiotic enhanced the fish's innate immune response. In order to improve water quality, fish growth, and antioxidant activities together with innate the immune responses, Bacillus species mixture (SANOLIFE®PRO-W) can be recommended to be used in Nile tilapia aquaculture. [ABSTRACT FROM AUTHOR]

Bacillus velezensis M3-1 strain isolated from the sediment of Myriophyllum aquatium constructed wetlands was found to efficiently convert NO 3 −-N to NO 2 −-N, and the requirements for carbon source addition were not very rigorous. This work demonstrates, for the first time, the feasibility of using the synergy of anammox and Bacillus velezensis M3-1 microorganisms for nitrogen removal. In this study, the possibility of M3-1 that converted NO 3 −-N produced by anammox to NO 2 −-N was verified in an anaerobic reactor. The NO 3 −-N reduction ability of M3-1 and denitrifying bacteria in coupling system was investigated under different C/N conditions, and it was found that M3-1 used carbon sources preferentially over denitrifying bacteria. By adjusting the ratio of NH 4 +-N to NO 2 −-N, it was found that the NO 2 −-N converted from NO 3 −-N by M3-1 participated in the original anammox.The nitrogen removal efficacy (NRE) of the coupled system was increased by 12.1%, compared to the control group anammox system at C/N = 2:1. Functional gene indicated that it might be a nitrate reducing bacterium.This study shows that the nitrate reduction rate achieved by the Bacillus velezensis M3-1 can be high enough for removing nitrate produced by anammox process, which would enable improve nitrogen removal from wastewater. [ABSTRACT FROM AUTHOR]

Dendrobium ovatum is an epiphytic orchid endemic to the Western Ghats of India. Due to its valuable medicinal and therapeutic properties, the plant has become extensively sought after, leading to its classification as 'threatened' in the latest research findings. The present study aims to identify the surface-associated and endophytic bacterial associates of Dendrobium ovatum, which may be of great significance from a conservation standpoint. The investigation resulted in isolating and identifying 21 bacterial isolates representing six genera from the absorption roots, stem, and leaves. Bacillus was the most dominant genus, with seven representative species from root and stem segments. Enterobacter formed the second most dominant genus, with four representatives from leaf and stem. Bacillus cereus was found to be the most prevalent species, with a relative frequency of 28.57%. Root segments were found to be the most diverse tissue compared to stem and leaves. The study concluded that each tissue represents a unique ecological niche harbouring specific bacterial associate. The study also illuminates the intricacies of the orchids' microbial community structure and forms the first documentation of bacterial associates of the threatened endemic orchid D. ovatum. Key policy insights: First report focussing on the bacterial associates of the threatened orchid, D. ovatum. Twenty-one bacterial isolates were identified, representing six genera. Each tissue of the orchid represents a distinct ecological niche. Reports the PGP traits of the isolates. Points to the importance of the conservation of holobionts. [ABSTRACT FROM AUTHOR]

BACKGROUND: Epicoccum sorghinum is a pathogenic fungus that causes leaf spot in a wide range of plants, including maize, and synthesizes the mycotoxin tenuazonic acid (TEA), which is carcinogenic. Despite the relevant economic and yield losses caused by E. sorghinum worldwide, methods for the control of this pathogen are lacking. RESULTS: In this work, the efficacy of Bacillus‐produced dipicolinic acid (DPA) for control of E. sorghinum was evaluated using in vitro and in vivo assays, and compared with the efficacy of three commercial fungicides, including carbendazim, prochloraz, and thiram. DPA inhibited E. sorghinum mycelial growth, and conidia germination, and produced important alterations in E. sorghinum hyphae. Interestingly, 10 mM DPA reduced TEA biosynthesis by 86.6%. Although DPA rapidly degraded on maize leaves, 10 mM DPA showed higher preventive (67.4% lesion length inhibition) and inhibitory (89.5% lesion length inhibition) efficacies for the control of E. sorghinum on maize leaves compared to the commercial fungicides. CONCLUSIONS: Collectively, this study presents the first method for the control of E. sorghinum on maize and demonstrates that DPA application is a suitable approach to inhibit E. sorghinum symptoms in plants and TEA biosynthesis. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

ABSTRACT The present research was aimed to isolate potential probiotic organisms from dairy products locally made in and around the Saurashtra region of Gujarat. A total of 224 colonies were screened for primary attributes. Based on the results, 70 isolates were carried further for secondary screening. Out of these, only 23 isolates were further tested for antioxidant activities. Only 6 potential probiotic strains were found to have all the probiotic attributes. These isolates demonstrated survivability up to 4 h at pH ≤ 3, bile concentration ≥ 1.5%, autoaggregation ability ≥ 81.08%, and cell surface hydrophobicity more than 70% while using toluene as the test hydrocarbon. The promising six isolates were subjected to 16S rRNA sequencing for species‐level identification and found to be belonging to the genus Bacillus, Enterococcus, and Lactobacillus. The isolates demonstrated higher antioxidant potential as determined by ABTS, DPPH, and FRAP methods. For all three methods, L. rhamnosus was taken as a positive control that showed 85.61%, 39.56%, and 78.18% reduction of free radicals as determined by the ABTS, DPPH, and FRAP methods, respectively. Compared to this, Limosilactobacillus fermentum BAB 7912 demonstrated the highest reduction of ABTS radicals (83.45%), while Bacillus subtilis BAB 7918 reduced 29.95% DPPH free radicals and Bacillus spizizenii BAB 7915 reduced 80.93% ferric ions as determined by the FRAP method. Isolates were subjected to 16S rRNA sequencing for species‐level identification and found to be belonging to genus Bacillus, Enterococcus, and Lactobacillus. [ABSTRACT FROM AUTHOR]

The diagnosis of anthrax, a zoonotic disease caused by Bacillus anthracis can be complicated by detection of closely related species. Conventional diagnosis of anthrax involves microscopy, culture identification of bacterial colonies and molecular detection. Genetic markers used are often virulence gene targets such as Bacillus anthracis protective antigen (pagA, as also called BAPA, occurring on plasmid pXO1), lethal factor (lef, on pXO1), as well as chromosomal (Ba-1) and plasmid (capsule-encoding capB/C, located on pXO2). Combinations of genetic markers using real-time/quantitative polymerase chain reaction (qPCR) are used to confirm B. anthracis from culture but can also be used directly on diagnostic samples to avoid propagation and its associated biorisks and for faster identification. We investigated how the presence of closely related species could complicate anthrax diagnoses with and without culture to standardise the use of genetic markers using qPCR for accurate anthrax diagnosis. Using blood smears from 2012–2020 from wildlife mortalities (n = 1708) in Kruger National Park in South Africa where anthrax is endemic, we contrasted anthrax diagnostic results based on qPCR, microscopy, and culture. From smears, 113/1708 grew bacteria in culture, from which 506 isolates were obtained. Of these isolates, only 24.7% (125 isolates) were positive for B. anthracis based on genetic markers or microscopy. However, among these, merely 4/125 (3.2%) were confirmed B. anthracis isolates (based on morphology, microscopy, and sensitivity testing to penicillin and gamma-phage) from the blood smear, likely due to poor survival of spores on stored smears. This study identified B. cereus sensu lato, which included B. cereus and B. anthracis, Peribacillus spp., and Priestia spp. clusters using gyrB gene in selected bacterial isolates positive for pagA region using BAPA probe. Using qPCR on blood smears, 52.1% (890 samples) tested positive for B. anthracis based on one or a combination of genetic markers which included the 25 positive controls. Notably, the standard lef primer set displayed the lowest specificity and accuracy. The BAPA+lef+Ba-1 combination showed 100% specificity, sensitivity, and accuracy. Various marker combinations, such as Ba-1+capB, BAPA+capB, Ba-1+BAPA+capB+lef, and BAPA+lef+capB, all demonstrated 100.0% specificity and 98.7% accuracy, while maintaining a sensitivity of 96.6%. Using Ba-1+BAPA+lef+capB, as well as Ba-1+BAPA+lef with molecular diagnosis accurately detects B. anthracis in the absence of bacterial culture. Systematically combining microscopy and molecular markers holds promise for notably reducing false positives. This significantly enhances the detection and surveillance of diseases like anthrax in southern Africa and beyond and reducing the need for propagation of the bacteria in culture. Authors summary: Our research tackles the challenges of diagnosing anthrax, a severe disease caused by the bacterium Bacillus anthracis, especially in regions where similar bacteria coexist. Traditional methods of identifying anthrax involve microscopic examination, bacterial culture, and genetic testing. We aimed to enhance the accuracy and speed of genetic testing to identify anthrax directly from samples, without the need for bacterial culture, thereby reducing the associated risks. We analysed blood samples from wildlife deaths in Kruger National Park, South Africa, where anthrax is common. By applying advanced genetic tests, we found that over half of the samples tested positive for anthrax. We discovered that combining certain genetic markers significantly improved the accuracy of these tests, reaching up to 100% accuracy. This method helps reduce false positives and enhances the reliability of anthrax detection. Our findings suggest that using a combination of genetic markers can accurately identify anthrax directly from blood samples, potentially bypassing the need for bacterial culture. This approach not only speeds up the diagnostic process but also improves disease monitoring and management. This is particularly important for regions like southern Africa, where anthrax poses a significant threat to wildlife health. Our work contributes to better conservation efforts and a deeper understanding of how to control anthrax outbreaks effectively. [ABSTRACT FROM AUTHOR]

Bacillus velezensis is a species of Bacillus that has been widely investigated because of its broad- spectrum antimicrobial activity. However, most studies on B. velezensis have focused on the biocontrol of plant diseases, with few reports on antagonizing Salmonella Typhimurium infections. In this investigation, it was discovered that B. velezensis HBXN2020, which was isolated from healthy black pigs, possessed strong anti- stress and broad- spectrum antibacterial activity. Importantly, B. velezensis HBXN2020 did not cause any adverse side effects in mice when administered at various doses (1χ107, 1χ108, and 1χ109 CFU) for 14 days. Supplementing B. velezensis HBXN2020 spores, either as a curative or preventive measure, dramatically reduced the levels of S. Typhimurium ATCC14028 in the mice's feces, ileum, cecum, and colon, as well as the disease activity index (DAI), in a model of infection caused by this pathogen in mice. Additionally, supplementing B. velezensis HBXN2020 spores significantly regulated cytokine levels (Tnfa, Il1b, Il6, and Il10) and maintained the expression of tight junction proteins and mucin protein. Most importantly, adding B. velezensis HBXN2020 spores to the colonic microbiota improved its stability and increased the amount of beneficial bacteria (Lactobacillus and Akkermansia). All together, B. velezensis HBXN2020 can improve intestinal microbiota stability and barrier integrity and reduce inflammation to help treat infection by S. Typhimurium. [ABSTRACT FROM AUTHOR]

Background Objectives Methods Results Conclusion Bacillus Calmette–Guérin (BCG) injected during the COVID‐19 convalescence period was safe and enhanced recovery from anosmia and dysgeusia in the acute phase.To report the long‐term results of the BATTLE trial, BCG vaccine in adults with mild COVID‐19.Design: Double‐blind, placebo‐controlled, randomized (1:1) clinical trial. Intervention: BCG intradermal vaccine and placebo. Patients: A total of 157 BCG and 142 placebo recipients participated in the 6‐month follow‐up, and 97 BCG and 95 placebo recipients participated in the 12‐month follow‐up. Measurements: Long COVID symptoms and mechanistic analyses.BCG reduced hearing problems at 6 months (odds ratio [OR] = 0.26) and sleeping, concentration, memory, and vision problems at 12 months (OR = 0.45, 0.36, 0.38, and 0.36, respectively). Sensitivity analyses confirmed that long COVID‐19 symptoms were reduced at the 6‐ and 12‐month follow‐ups (p = 0.010 and 0.031, respectively). BCG's crossover interaction paradoxically increased hair loss in women and decreased it in men at 6 months (p = 0.032). BCG immunomodulation is likely mediated through inhibition of Fas ligand expression in the blood and increased induction of IL6, IL10, interferon‐induced transmembrane protein 3, and angiotensin‐converting enzyme 2 in cultured human macrophages.Long‐term follow‐up of the BATTLE trial participants revealed that BCG protects against long COVID development if administered within the COVID‐19 convalescence period. The response to BCG was subject‐specific, including a paradoxical crossover interaction based on sex. Limitations: Not tested for previous mycobacterial exposure; loss to follow‐up, particularly at 12 months. [ABSTRACT FROM AUTHOR]

Flowering plants can be introduced in modern agroecosystems to support resident natural enemies in the context of Conservation Biological Control (CBC). Buckwheat (Fagopyrum esculentum) (Polygonales: Polygonaceae) has been shown to enhance the longevity of several parasitoids through the provision of high quality and easily accessible floral nectar. Yet floral nectar is ubiquitously colonized by microbes which can change nectar chemistry with consequences for parasitoids. Nonetheless, how bacteria associated with buckwheat floral nectar affect parasitoid performance is not known. In this study, adult females of Trissolcus basalis (Hymenoptera: Scelionidae) and Ooencyrtus telenomicida (Hymenoptera: Encyrtidae), two parasitoids of Nezara viridula (Hemiptera: Pentatomidae), were provided with synthetic nectar fermented by 14 bacterial isolates originating from buckwheat nectar. We recorded the effect of bacterial fermentation on female longevity and nectar chemistry. In the case of T. basalis, females consuming nectar fermented by Bacillus sp., Brevibacillus sp., Brevibacterium frigoritolerans, Saccharibacillus endophyticus, and Terribacillus saccharophilus significantly enhanced their longevity compared with females fed with non‐fermented nectar. For O. telenomicida, enhanced longevity was recorded only in the case of B. frigoritolerans and Pantoea dispersa. For both parasitoids, no negative effects due to bacterial fermentation of nectar were recorded. Chemical investigations of bacteria‐fermented nectars revealed an increased diversity in the composition of sugars and sugar alcohols, whereas non‐fermented nectar only contained sucrose. Our findings show that nectar‐inhabiting bacteria are important “hidden players” in the interactions between flowers and parasitoids, an indication that a better understanding of plant–microbe–insect interactions could improve CBC programmes. [ABSTRACT FROM AUTHOR]

Macrolactins have attracted considerable attention due to their value and application in medicine and agriculture. However, poor yields severely hinder their broader application in these fields. This study aimed to improve macrolactins production in Bacillus siamensis using a combined atmospheric and room-temperature plasma mutagenesis and a microbial microdroplet culture system. After 25 days of treatment, a desirable strain with macrolactins production 3.0-fold higher than that of the parental strain was successfully selected. The addition of 30 mg/L ZnSO 4 further increased macrolactins production to 503 ± 37.6 μg/mL, representing a 30.9 % improvement in production compared to controls. Based on transcriptome analysis, the synthesis pathways of amino acids, fengycin, and surfactin were found to be downregulated in IMD4036. Further fermentation experiments confirmed that inhibition of the comparative fengycin synthesis pathway was potentially driving the increased production of macrolactins. The strategies and possible mechanisms detailed in this study can provide insight into enhancing the production of other secondary metabolites toxic to the producer strains. [Display omitted] • Saline stress tolerant mutant was obtained successfully using an ARTP-MMC strategy. • The desired strain produced 3.0-fold higher macrolactins with a titer of 327.6 μg/mL. • Macrolactins titer was elevated to 503 μg/mL by adding 30 mg/L zinc sulfate. • Macrolactins metabolism of Bacillus siamensis was uncovered using transcriptome studies. • Combined ARTP-MMC strategy is beneficial for rapid evolution in microbial breeding. [ABSTRACT FROM AUTHOR]

This study showcases 121 new genomes of spore-forming Bacillales from strains collected globally from a variety of habitats, assembled using Oxford Nanopore long-read and MGI short-read sequences. Bacilli are renowned for their capacity to produce diverse secondary metabolites with use in agriculture, biotechnology, and medicine. These secondary metabolites are encoded within biosynthetic gene clusters (smBGCs). smBGCs have significant research interest due to their potential as sources of new bioactivate compounds. Our dataset includes 62 complete genomes, 2 at chromosome level, and 57 at contig level, covering a genomic size range from 3.50 Mb to 7.15 Mb. Phylotaxonomic analysis revealed that these genomes span 16 genera, with 69 of them belonging to Bacillus. A total of 1,176 predicted BGCs were identified by in silico genome mining. We anticipate that the open-access data presented here will expand the reported genomic information of spore-forming Bacillales and facilitate a deeper understanding of the genetic basis of Bacillales' potential for secondary metabolite production. [ABSTRACT FROM AUTHOR]

Simple Summary: A feather-degrading bacterium, Bacillus velezensis PN1, was isolated, and solid-state fermentation conditions were optimized. The resulting fermented feather meal (FFM) was evaluated for bioavailability in broilers. B. velezensis PN1 showed the highest feather degradation rate, with optimal fermentation achieved at 37 °C for 48–72 h. FFM2, produced with 65% moisture at 37 °C for 48 h, was compared with FFM1 (produced at 27 °C) and commercial hydrolyzed feather meal (HFM). FFM2 was found to be more suitable for large-scale production due to its amino acid profile and fermentation efficiency. In a broiler growth trial, diets containing 5% FFM2 showed no significant difference in body weight, feed conversion ratio, or performance efficiency compared to the 5% HFM group (p > 0.05). However, both FFM2 and HFM groups showed lower weight gain than the 5% fish meal (FM) group (p < 0.05). Without supplemental amino acids, growth performance did not differ between FFM2 and HFM groups (p > 0.05). In conclusion, FFM produced by B. velezensis PN1 can completely replace HFM when included at 5% in broiler diets. In this study, an effective feather-degrading bacterium was isolated and the solid-state fermentation condition for feather degradation was optimized. The resulting fermented feather meal (FFM) was evaluated for its bioavailability in broilers. Four Bacillus strains were examined for feather degradation rates, with Bacillus velezensis PN1 exhibiting the highest rate (83.24%, p < 0.05). A 3 × 3 × 3 factorial design was used to test substrate moisture content (45%, 55%, 65%), temperature (27 °C, 37 °C, 47 °C), and incubation time (24, 48, 72 h) for optimized fermentation conditions. In vitro pepsin digestibility (IVPD) revealed a significant interaction between temperature and time (p < 0.05), and the optimal performance was achieved at 37 °C for 72 h, followed by 37 °C for 48 h. Considering production time and cost, FFM2 (produced with 65% moisture at 37 °C for 48 h) was further compared with FFM1 (produced under the same conditions but at a lower temperature of 27 °C), and commercial hydrolyzed feather meal (HFM). IVPD did not differ significantly between FFM1, FFM2, and HFM, as they all showed significantly higher digestibility compared to raw feathers (RFs). FFM1, as well as FFM2, had significantly higher histidine and lysine concentrations than RF (p < 0.05), while FFM2 had a significantly lower cysteine content (p < 0.05). Based on fermentation conditions and amino acid composition, FFM2 was considered more suitable for large-scale production and was used in a broiler growth trial. The inclusion of 5% FFM2 in the broiler diet did not significantly affect body weight at 35 days compared to the 5% HFM group (p > 0.05), although both groups showed significantly lower weight gain than the 5% fish meal (FM) group (p < 0.05). The feed conversion ratio and performance efficiency factor did not differ significantly between the FFM2, HFM, and FM groups (p > 0.05). In groups fed diets without supplemental crystalline amino acids, growth performance did not significantly differ between the HFM and FFM2 groups (p > 0.05), although both performed significantly worse than groups with amino acid supplementation. In conclusion, FFM produced by B. velezensis PN1 through solid-state fermentation enhances feather bioavailability in poultry and can completely replace HFM when included at 5% in broiler diets, offering a potential sustainable alternative for poultry nutrition on a commercial scale. [ABSTRACT FROM AUTHOR]

Objectives: Food products are often contaminated by pathogens and spoilage bacteria. Most of them can form biofilms, a community of cells embedded in protective extracellular matrix layers resistant to harsh conditions, including antibiotics. Therefore, alternative antibiofilm agents are required to overcome biofilm formation. This study aims to determine and quantify the antibiofilm activity of supernatants from plant-associated bacteria against biofilms of foodborne pathogen and food spoilage bacterium, namely Bacillus cereus and Bacillus subtilis. Results: Plant-associated bacteria (PAB) have shown promising antibiofilm activities against biofilm-forming pathogens in previous studies. Thirteen PAB isolated from Ternate, Indonesia were used in this study. Supernatants of PAB were subjected to antimicrobial activity and quorum quenching detection, both using the well diffusion method. Four supernatants inhibited the growth of B. subtilis, but none affected the growth of B. cereus. Eight supernatants were able to disrupt the quorum sensing system of an indicator bacterium, wild-type Chromobacterium violaceum. Biofilm inhibition and destruction were quantified using 96-well microplates. The highest biofilm inhibition and destruction activities of PAB supernatants against each of B. cereus and B. subtilis biofilms were > 76%, and were later confirmed by light microscope and scanning electron microscope. Brine shrimp lethality assay (BSLA) was conducted and revealed that the selected PAB supernatants were non-toxic. The 16S rRNA gene of PAB were sequenced and they showed similarities to Bacillus, Priestia, and Chryseobacterium. Compounds in the supernatants were determined by GC–MS which revealed contents of fatty acids, ethyl esters, and diketopiperazines. Therefore, PAB supernatants have potential as antibiofilm agents against biofilm formed by Bacillus cereus and Bacillus subtilis. [ABSTRACT FROM AUTHOR]

Background: Vitamin B12 is a crucial B-group vitamin, first isolated from the liver due to its role in combating pernicious anemia. It is distinguished by its unique and complex structure, which makes its chemical synthesis challenging and expensive. Consequently, vitamin B12 is alternatively obtained through microbial fermentations. Molasses, an affordable and safe agro-industrial waste, can be used as a carbon source for vitamin B12 production, offering a cost-effective alternative to expensive sugars in the production medium. Results: A total of 87 yeast, actinomycete, and bacterial isolates were screened for vitamin B12 production, with 15 isolates showing high productivity. Bacillus isolates were selected for further analysis using MALDI-TOF and molecular identification. These isolates were identified as four strains of Bacillus subtilis (MZ08, JT10, BY11, and JT17), one strains of Bacillus sp. (CB09), and one strain of Peribacillus acanthi (MZ01). Genetic circuits associated with vitamin B12 production were demonstrated in a closely related strain of Peribacillus acanthi MZ01 strain. Three strains (MZ01, MZ08, and JT17) were selected for further evaluation of vitamin B12 productivity under different sugar types (glucose, sucrose, fructose, lactose, and galactose) and varying inoculum sizes. The inoculum size significantly impacted vitamin B12 production, with an increase from 5 to 10% enhancing yields. The ability of the strains to produce vitamin B12 varied depending on the type of sugar used. Peribacillus acanthi MZ01 strain showed the highest productivity and subsequently, selected for optimizing vitamin B12 production conditions using response surface methodology. Furthermore, the optimized conditions were then applied to molasses-based medium to achieve high vitamin B12 yields by MZ01 strain. Conclusion: In this study, Peribacillus acanthi was characterized for the first time as a vitamin B12 producer, demonstrating high productivity among various tested strains. The optimization of production conditions using response surface methodology, further enhanced vitamin B12 yields, showcasing the strain's efficiency in microbial fermentations. This research also highlights the potential of using molasses as a cost-effective alternative carbon source, significantly reducing production costs. [ABSTRACT FROM AUTHOR]

Aquaponic systems are food production systems that combine aquaculture and hydroponic in a closed recirculation system where water provides nutrients to plants while plants purify water for fish. In this system, tilapia is the most commonly cultured fish and can be easily integrated with vegetable cultivation. However, tilapia host a diverse microbiota some of which are pathogenic and can infect humans. Previous studies have reported contamination of lettuce by pathogenic bacteria which can cause human diseases. Thus, there is an urgent need to employ effective methods to control those bacteria, and Bacillus strains have been successfully used in this context. This systematic review aimed to provide a comprehensive overview of lettuce contamination by pathogenic bacteria and the use of Bacillus as probiotics to prevent diseases in aquaponics systems. This systematic review was performed using Preferred Reporting Items for Systematic Review and Meta-Analysis Statement (PRISMA) Guidelines. A total of 1,239 articles were retrieved and based on eligibility criteria, six articles were included after screening. The review revealed that Enterobacteriaceae, Coliforms, and Shiga Toxin-producing E. coli are the predominant bacteria contaminating lettuce leaves in Aquaponic systems, and Shiga Toxin-Producing E. coli can internalize in the lettuce leaves, putting public health at risk. The included studies did not report the presence of V. cholerae in lettuce grown in aquaponic systems, and the use of Bacillus as probiotics to control Escherichia coli and Vibrio Cholerae. Further research is needed to explore the potential of tilapia to act as a source of pathogenic bacteria that can contaminate lettuce, as well as to investigate the effectiveness of Bacillus strains as probiotics to control these bacteria and ensure food safety. [ABSTRACT FROM AUTHOR]

Background Results Conclusion Probiotics have excellent antioxidant and antibacterial effects and are also considered to be promising natural biological preservatives. This study examined the freeze–thaw stability of the antioxidant and antibacterial activity of probiotic Bacillus velezensis PJP10, and evaluated the effect of different concentrations of PJP10 (106, 107, and 108 CFU mL−1) on microbial growth, textural characteristics, physicochemical properties, and lipid oxidation of grass carp fillets during repeated freeze–thaw cycles.Freeze–thaw cycles had little effect on the antioxidant and antibacterial stability of PJP10. Treatment with the PJP10 strain slowed effectively the increase in Aeromonas spp. counts (ASC), pH, total volatile basal nitrogen (TVB‐N), and thiobarbituric acid (TBA) values of the freeze–thaw fish fillets. It maintained the textural quality of fillets, inhibiting the reduction of hardness, springiness, gumminess, cohesiveness, chewiness, and resilience values, and reduced lipid oxidation, as evidenced by decreased carbonyl values and conjugated diene values after multiple freeze–thaw cycles.Probiotic B. velezensis PJP10 had protective effects on microbiological, textural, and physicochemical properties, and lipid oxidation of grass carp fillets during repeated freeze–thaw storage, suggesting a potential application of this strain in the freeze–thaw preservation of freshwater fish. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

The plate counting method is a traditional and widely accepted technique for live cell counting, often employed for Bacillus enumeration and spore forming rate calculations. However, this method requires at least 12 h to generate results, making it unsuitable for real-time monitoring of bacterial growth status and spore transformation rate. Bacillus thuringiensis crystals, produced during sporulation, are widely used as microbial pesticides, with high demand for industrial scale production. Variations in cultivation conditions and harvest timing during large-scale pore production of Bacillus thuringiensis significantly affect spore forming rate, impacting crystallization yield. Nevertheless, there is a lack of real-time monitoring methods for spore conversion rate. Flow cytometry (FCM), a well-established technique for single-cell analysis in eukaryotic cells, has been successfully applied in bacterial detection in environmental and food samples. In this study, we introduced a rapid flow cytometry-based method for determining spore forming rate of Bacillus thuringiensis , with two nucleic acid dyes, SYTO24 and LDS751. The method enables dynamic monitoring of spore, vegetative cell, and viable but non-culturable/dead cell proportions during the whole cultivation process, and spore forming rate could be gained within 30 min. Data of spore forming rate by FCM method is consistent with that by plate counting method, offering a faster and more efficient approach for assessing sporulation status in industrial Bacillus thuringiensis microbial pesticide production. [ABSTRACT FROM AUTHOR]

The velvetbean caterpillar Anticarsia gemmatalis is one of the main soybean defoliators in Brazil. Currently, the main biopesticide used to control insect pests worldwide is the bacteria Bacillus thuringiensis (Bt), which produces entomopathogenic Crystal toxins (Cry) that act in the midgut of susceptible insects, leading them to death. The mode of action of Cry toxins in the midgut involves binding to specific receptors present on the brush border of epithelial cells such as aminopeptidase N (APN), alkaline phosphatase (ALP), cadherin, and others. Mutations in these receptors, among other factors, may be involved in the development of resistance; identification of functional Cry receptors in the midgut of A. gemmatalis is crucial to develop effective strategies to overcome this possible scenario. This study's goal is to characterize APNs of A. gemmatalis and identify a receptor for Cry1Ac in the midgut. The interaction of Bt spores with the midgut epithelium was observed in situ by immunohistochemistry and total aminopeptidase activity was estimated in brush border membrane vesicle (BBMV) samples, presenting higher activity in challenged individuals than in control ones. Ten APN sequences were found in a A. gemmatalis ' transcriptome and subjected to different in silico analysis, such as phylogenetic tree, multiple sequence alignment and identification of signal peptide, activity domains and GPI-anchor signal. BBMV proteins from 5th instar larvae were submitted to a ligand blotting using activated Cry1Ac toxin and a commercial anti-Cry polyclonal antibody; corresponding bands of proteins that showed binding to Cry toxin were excised from the SDS-PAGE gel and subjected to mass spectrometry analysis, which resulted in the identification of seven of those APNs. Quantitative PCR was realized to compare expression levels between individuals subjected to sublethal infection with Bt spores and control ones, presenting up- and downregulations upon Bt infection. From these results, we can infer that aminopeptidases N in A. gemmatalis could be involved in the mode of action of Cry toxins in its larval stage. [ABSTRACT FROM AUTHOR]

In this study, we aimed to use high‐throughput sequencing technology to systematically analyze the bacterial community structure during the box wheat Qu–making process to understand the succession of bacterial communities. To our knowledge, this is the first study in which mature Qu, raw materials, and the complete fermentation process of the box wheat Qu were analyzed. Significant differences in the distribution and abundance of the dominant bacteria were observed among these samples. Bacterial diversity was lowest in residual mature Qu, gradually increasing after moistening and fermentation and declining after reaching its peak on the fourth day. The predominant bacteria observed in residual mature Qu were Saccharopolyspora (81.64%), Weissella (3.39%), and Staphylococcus (3.06%). The most abundant bacteria in the moistened material were Pantoea (48.50%), Staphylococcus (12.10%), and Saccharopolyspora (11.61%). However, a rapid decline in Pantoea and Staphylococcus in box wheat Qu was observed on the first day of fermentation. Following fermentation, the most abundant bacteria were Saccharopolyspora (68.85%), Bacillus (19.94%), and Thermoactinomyces (4.70%). Nonmetric multidimensional scale and linear discriminant analysis effect size analyses revealed a significant difference in the bacterial community structure between the raw materials and samples obtained at the end of fermentation. These findings underscore the significant effect of the bacterial community structure of residual mature Qu on box wheat Qu. [ABSTRACT FROM AUTHOR]

This research delved into the effects of nutrient limitation on the level of sporulation and the cadmium adsorption capacity of the bacterium Bacillus sp. isolated from the rhizosphere of endemic soils in the Region of Valparaiso, Chile. The bacteria were subjected to nitrogen limitation in fed-batch mode and were compared to bacteria grown in batch culture without nutrient limitation. The cultures were carried out in a 3 L bioreactor with an external nitrogen supply of ammonium at a flow of 0.123 L h−1. The specific maximum growth rate was 0.42 h−1 in batch and 0.45 h−1 in the exponential phase of the fed-batch. The analysis of sporulation did not show any significant difference between the biomass coming from the fed-batch and batch cultures. It was found that maximum cadmium adsorption capacity varied with culture strategy. The dry biomass grown without nutrient limitation exhibited a maximum adsorption capacity for cadmium of 65.0 mg Cd g−1 biomass. Conversely, the limited biomass achieved a lower cadmium adsorption capacity of approximately 36.0 mg Cd g−1 biomass. FTIR analysis showed that nitrogen limitation induced changes in the composition of the outer cell wall, specifically an increase of deacetlylated polysaccharides, reducing the relative amount of secondary amines and proteins from the peptidoglycan matrix. Amino groups from acetylated polysaccharides and proteins have been associated elsewhere with greater cadmium affinity, which could explain the poor results obtained with the nitrogen-restricted biomass. This study shows that new physiological states displaying different adsorption capabilities were effectively obtained by engineering the cell coverage of the bacteria using varying culture strategies. The fed-batch culture proved to be a valuable tool for studying PGPR strains for biosorption and other applications. Exploring diverse nutrient limitations and other pollutants in this bacterium and other members of the PGPR family offer great opportunities to tailor biosorption strategies based on specific conditions, ultimately contributing to sustainable environmental solutions. [Display omitted] • Fed batch culture. • Promoting Growth Plant Rhizobacteria (PGPR). • Nutrient availability. • Adsorption characteristics. • FTIR analysis. [ABSTRACT FROM AUTHOR]

Fusarium wilt of banana, caused by Fusarium oxysporum f. sp. cubense tropical race 4 (Foc TR4), is a widely distributed soilborne disease that poses a serious threat to banana production. Many control measures have been implemented but have not been effective. Here, we evaluated a combined strategy for Fusarium wilt control that involves a biological agent (Bacillus velezensis strain EB1) and a bioactive compound (potassium sorbate). Our results showed that potassium sorbate inhibited Foc TR4 in a dose-dependent manner. Potassium sorbate did not limit the growth of EB1 in vitro; instead, it promoted the growth and antagonistic ability of EB1 by upregulating the expression of antagonism-related genes. In greenhouse experiments, the combined application of EB1 and potassium sorbate significantly reduced the disease index of Fusarium wilt by suppressing fungal growth in the roots and promoting plant growth. Overall, our results demonstrated that potassium sorbate and B. velezensis EB1 can be used together for the sustainable management of banana Fusarium wilt. [ABSTRACT FROM AUTHOR]

β-Galactosidase from Bacillus circulans ATCC 31382 (BgaD) is a biotechnologically important enzyme for the synthesis of β-galactooligosaccharides (GOS). Among its four isoforms, isoform A (BgaD-A) has distinct synthetic properties. Here, we present cryoelectron microscopy (cryo-EM) structures of BgaD-A and compare them with the known X-ray crystal structure of isoform D (BgaD-D), revealing substantial structural divergences between the two isoforms. In contrast to BgaD-D, BgaD-A features a flexible Big-4 domain and another enigmatic domain. The newly identified flexible region in BgaD-A is termed as "barrier domain 8," and serves as a barricade, obstructing the access of longer oligosaccharide substrates into the active site of BgaD-A. The transgalactosylation reactions catalyzed by both isoforms revealed that BgaD-A has a higher selectivity than BgaD-D in the earlier stages of the reaction and is prevailingly directed to shorter galactooligosaccharides. This study improves our understanding of the structural determinants governing β-galactosidase catalysis, with implications for tailored GOS production. [Display omitted] • BgaD-A cryo-EM structures revealed structural differences between BgaD isoforms • BgaD-A contains a "Barrier domain 8" that is lacking in BgaD-D • Longer oligosaccharides cannot fit into the active site of BgaD-A • Structural differences explain the observed transgalactosylation specificities Hovorková et al. reveal structural differences between the β-galactosidase (BgaD) isoforms A and D and identify a flexible "Barrier domain 8" in BgaD-A that might obstruct longer oligosaccharide substrates. This study improves our understanding of the structural determinants governing β-galactosidase catalysis, which is of interest for tailored GOS production. [ABSTRACT FROM AUTHOR]

Plant growth-promoting rhizobacteria colonize the rhizosphere through dynamic and intricate interactions with plants, thereby providing various benefits and contributing to plant growth. Moreover, increasing evidence suggests that plant growth-promoting rhizobacteria affect plant tolerance to abiotic stress, but the underlying molecular mechanisms remain largely unknown. In this study, we investigated the effect of Bacillus velezensis strain GH1-13 on drought stress tolerance in rice. Phenotypical analysis, including the measurement of chlorophyll content and survival rate, showed that B. velezensis GH1-13 enhances rice tolerance to drought stress. Additionally, visualizing ROS levels and quantifying the expression of ROS-scavenging genes revealed that GH1-13 treatment reduces ROS accumulation under drought stress by activating the expression of antioxidant genes. Furthermore, the GH1-13 treatment stimulated the jasmonic acid response, which is a key phytohormone that mediates plant stress tolerance. Together with the result that jasmonic acid treatment promotes the expression of antioxidant genes, these findings indicate that B. velezensis GH1-13 improves drought tolerance in rice by reducing ROS accumulation and suggest that activation of the jasmonic acid response is deeply involved in this process. [ABSTRACT FROM AUTHOR]

Soybean cyst nematode (SCN) poses a significant challenge to red kidney beans cultivation, resulting in yield losses and quality deterioration. This study investigates the molecular mechanisms using Tandem Mass Tag (TMT) based proteomics technology to explore how the plant growth-promoting rhizobacterium (PGPR) Bacillus velezensis A-27 enhances the resistance of red kidney beans against SCN. The results revealed that out of 1,374 differentially expressed proteins (DEPs) in the red kidney beans roots, 734 DEPs were upregulated and 640 DEPs were downregulated in the A-27 + J2 vs J2 treatment group. KEGG analysis revealed that 14 DEPs were involved in the α-LeA metabolic pathway, crucial for the biosynthesis of jasmonic acid (JA) in plants. Quantitative real-time PCR (qRT-PCR) confirmed the upregulation of 4 key genes (PLA1, AOS , AOC , ACX) in the JA biosynthesis pathway, while enzyme-linked immunosorbent assay (ELISA) demonstrated a significant increase in JA content in the roots. The study demonstrates that B. velezensis A-27 stimulates induced systemic resistance (ISR) in red kidney beans, and induce JA biosynthesis by regulating the expression of key enzymes in the α-LeA metabolic pathway. This enhances the plant's defense against SCN, providing a theoretical foundation for the potential use of B. velezensis A-27 as a biocontrol agent for managing SCN in leguminous crops. [ABSTRACT FROM AUTHOR]

An alkaline active L-glutaminase (BALG) producing bacterium was screened and identified from seamount sediment samples of the Arabian Sea. The isolate was confirmed to be Bacillus australimaris NIOT30 based on morphological characteristics and 16 S rRNA gene sequencing. The glutaminase gene, balg was PCR amplified, cloned and expressed in E. coli BL21 (DE3) host. The molecular weight of purified BALG was estimated to be 36 kDa and the enzyme showed a specific activity of 507 ± 27 Umg−1 against L-glutamine under optimal assay conditions of pH 7.0 and temperature at 37 °C for 15 min. The enzyme showed maximum activity at pH 7 and retained 95% activity at pH 10. BALG retained a relative activity of about 82% and 45% at 45 °C and 60 °C respectively. The kinetic parameters of BALG, Km and Kcat/Km were determined to be of 210 ± 11 mM and 4.4 × 102 M s−1 respectively. Homology modeling and substrate ligand interaction studies revealed the stability of the enzyme-substrate complex. The present study highlights the characterization of a highly active L-glutaminase from B. australimaris NIOT30. Further, mutational analyses of ligand binding residues would show insights into the affinity of L-Glutaminase. [ABSTRACT FROM AUTHOR]

Arbuscular mycorrhizal (AM) fungi (e.g., Rhizophagus species) recruit specific bacterial species in their hyphosphere. However, the chemical interplay and the mutual benefit of this intricate partnership have not been investigated yet, especially as it involves bacteria known as strong producers of antifungal compounds such as Bacillus velezensis. Here, we show that the soil-dwelling B. velezensis migrates along the hyphal network of the AM fungus R. irregularis , forming biofilms and inducing cytoplasmic flow in the AM fungus that contributes to host plant root colonization by the bacterium. During hyphosphere colonization, R. irregularis modulates the biosynthesis of specialized metabolites in B. velezensis to ensure stable coexistence and as a mechanism to ward off mycoparasitic fungi and bacteria. These mutual benefits are extended into a tripartite context via the provision of enhanced protection to the host plant through the induction of systemic resistance. [Display omitted] • B. velezensis colonizes the entire mycelial network more efficiently than roots • Bacillus uses fungal hyphae as highways for soil invasion and to colonize new plant • The lipopeptide surfactin plays key roles in the chemical ecology of the interaction • The microbial partnership enhances the systemic resistance of tomato against Botrytis Anckaert et al. investigate the dynamics of Rhizophagus hyphae colonization by B. velezensis. Reduced production of bacterial toxic metabolites triggered by the fungus leads to an unsuspected stable coexistence. This interaction brings benefits to both microbes and provides positive effects to the host plant, which is more resistant to disease. [ABSTRACT FROM AUTHOR]

Accumulation of coal gangue (CG) poses significant risks to both human health and ecological systems, underscoring the urgent need for sustainable methods to utilize this abundant waste material effectively. In this study, we successfully screened and isolated the Bacillus velezensis bacterial strain to enhance the solubilization of potassium (K) and phosphorus (P) nutrients from CG. The study employed XRD, FTIR, SEM, and HPLC techniques to investigate the underlying mechanisms of CG solubilization. Various parameters such as CG particle size, incubation time, initial inoculation ratio, concentration of CG, pH, and temperature were optimized to maximize solubilization efficiency. The Bacillus velezensis bacterium can dissolve minerals of CG by adhering to its surface and secreting various kinds of organic acids, particularly succinic acid. Pot experiments further demonstrated that Bacillus velezensis, in conjunction with CG, promotes alfalfa growth. These combined findings suggest that Bacillus velezensis and coal gangue hold promising potential as mineral soil conditioners, effectively enhancing plant growth. This approach presents a viable alternative for the environmentally responsible utilization of CG, addressing both ecological concerns and agricultural sustainability. IMPORTANCE Coal gangue piles not only occupy significant amounts of arable land but also cause serious environmental pollution. Therefore, finding sustainable methods for the clean utilization of CG is imperative. Although previous studies have shown that bacteria can promote the solubilization of available phosphorus and available potassium from CG, their impact on promoting plant growth remains understudied. To our knowledge, this study is the first to demonstrate the potential of Bacillus velezensis in enhancing the effectiveness of CG as a mineral fertilizer to support alfalfa growth. The evidence presented in this study provides an ecological strategy for the utilization of CG. [ABSTRACT FROM AUTHOR]

Gloriosa superba L., a medicinally important plant, is often affected by leaf blight disease caused by Alternaria alternata, which compromises its productivity. This study explores the protective effects of Bacillus australimaris endophyte (NBRI GS34), demonstrating that its inoculation not only inhibits the disease but also promotes plant growth and increases the concentrations of bioactive metabolites. Co-culturing NBRI GS34 with A. alternata significantly boosts protease (30–50%) and chitinase (6–28%) activities, evidencing a synergistic interaction. Scanning electron microscopy and GC-MS analysis confirm NBRI GS34's antagonistic action and reveal antifungal compounds like undecanoic acid and benzene carboxylic acid in treatments. Greenhouse experiments show a 78% reduction in disease incidence with NBRI GS34 treatment, enhancing vegetative growth and upregulating defense-related genes. Additionally, HPLC analysis reveals increased gloriosine and colchicine concentrations by 52% and 33%, respectively. These findings suggest NBRI GS34 could serve as a sustainable fungicide alternative, enhancing the production of medically valuable compounds and highlighting its potential pharmaceutical applications. [ABSTRACT FROM AUTHOR]

Phytonematodes are responsible for causing significant harm and reducing yields in various agricultural crops. To minimize losses caused by phytonematodes and meet the high demand for agricultural production, it is important to develop effective strategies with minimal environmental impact to manage this biotic stress. Due to the adverse environmental effects associated with synthetic pesticides, it is imperative to use beneficial bacteria, such as Bacillus and Pseudomonas spp., for biocontrol purposes to control phytonematode infestation in agricultural settings. This approach has gained considerable attraction, as there is a promising market for eco-friendly biopesticides based on bacteria that can effectively manage phytonematodes. Furthermore, biocontrol strains of Bacillus and Pseudomonas have the potential to enhance crop productivity by producing various substances that promote plant growth and development. This review aims to explore the role of Bacillus and Pseudomonas spp. in phytonematode management, elucidate different mechanisms by which these bacteria suppress nematode populations, and discuss the future prospects of utilizing these bacteria in agriculture. [ABSTRACT FROM AUTHOR]

This study aimed to isolate bacteria that coexist with the edible mushroom Grifola frondosa when it is cultured on wood, and to determine their interactions; in turn, the aim was to find bacteria that stimulate mycelial growth so as to decrease the time required for spawn preparation on potato dextrose agar (PDA). Some Pseudomonas, Dyella, Bacillus , and Priestia spp. isolated from the cultivation surroundings of G. frondosa had a positive effect on the mycelial growth of the fungus in PDA. However, some isolated bacteria had a severe negative effect on the mycelial growth, especially Burkholderia spp. Thus, both mycelial-promoting bacteria and potentially pathogenic bacteria coexist with G. frondosa in cultivation. Enzyme activity assays indicated that some wood-degrading bacteria inhabit the cultivation surroundings of G. frondosa , and these bacteria probably help the fungus to degrade wood (especially cellulose). [ABSTRACT FROM AUTHOR]

The present experimental investigation was executed to evaluate the combined effect of probiotic bacterium Bacillus coagulans along with herb Mentha piperita on histological architecture; and extent of DNA damage after challenge trial with pathogenic bacterium Aeromonas hydrophila in Catla catla. In this experiment, six dietary treatments in triplicate were formulated; C0, M3 and M6 in which M. piperita was supplemented at 0, 3, 6 g kg-1 of feed, while in dietary treatments CP, MP3 and MP6; supplementation of probiotic bacterium B. coagulans at the rate of 3000 CFU g-1 was done along with different inclusion level of M. piperita (0, 3, 6 g kg-1 of feed). Fishes were fed for 60 days on different dietary treatments. Growth performance, histological study and extent of DNA damage using comet assay was examined. Significantly (p < 0.05) high growth % gain in BW was observed in treatment MP6 followed by treatment M6. The histological analysis clearly revealed that dietary M. piperita without or with probiotic bacterium can protect the histoarchitecture of intestinal layers and liver even after challenge with A. hydrophila. Analysis of various comet parameters (tail length, olive moment, tail DNA, head DNA) affirmed that M. piperita supplemented diet can reduce the extent of DNA damage in fishes after challenge trial with A. hydrophila, however dietary supplementation of probiotic bacterium along with M. piperita can reduce the DNA damage up to larger extent confirming its combined protective effect of supplemented diets. [ABSTRACT FROM AUTHOR]

In this work, phosphoric acid pretreatment (0.6% H3PO4, 160 °C, 40 min) of eucalyptus residues was performed to recover the hemicellulosic fraction for further conversion to l‐lactic acid by fermentation with Weizmannia coagulans DSM 2314 (formerly Bacillus coagulans). The hemicellulosic hydrolysate was composed of xylosaccharides 24.8 g L–1 (mainly xylose, 20.3 g L–1), acetic acid 7.8 g L–1, furfural 0.7 g L–1, and acid‐soluble lignin (ASL) 2.1 g L–1. It was subsequently purified by using anion exchange or adsorption resins. Different liquor‐to‐resin ratios were evaluated to obtain a high concentration of xylosaccharides in the eluate and thorough removal of components that inhibit lactic fermentation. The best performance was observed when using Amberlite‐XAD‐4 resin at a liquor‐to‐resin ratio of 3:1. An eluted hydrolysate was obtained, preserving 80% of the xylosaccharides and effectively removing almost all furfural, 90% of ASL, and 32% of acetic acid. Subsequently, l‐lactic acid production by W. coagulans DSM 2314 was evaluated using concentrated nondetoxified and detoxified hydrolysate obtained with a vacuum oven. For the nondetoxified hydrolysate, 12 g L–1 of l‐lactic acid was obtained after 48 h showing a yield of 0.56 glactic acid gsugar–1 and a xylose consumption of 62%. The detoxification of the liquor significantly improved the fermentation performance of W. coagulans, resulting in a concentration of 16 g L–1 of lactic acid after 24 h, with a yield of 0.73 glactic acid gsugar–1, and almost complete xylose consumption. [ABSTRACT FROM AUTHOR]

Among the genera in this family, Styrax is unique in that it yields benzoin resin, a resinous substance. Usually, when sharp items lacerate the bark, this resin is secreted. Because of its fragrant qualities, it has been used for centuries in cosmetics and fragrances all over the world. Additionally, Styrax species have long been employed in herbal remedies for a variety of ailments. The antibacterial characteristics of Styrax tonkinensis essential oil (STEO) were the focus of this study. The antimicrobial activity was compared to bacteria, both Gram-positive (G+) and Gram-negative (G-), using inhibition zones in agar media, minimum inhibitory concentration (MIC) bioassays and in vapour phase on fruits and vegetables model. The findings showed that STEO was very successful in inhibiting bacteria that were G+ (Bacillus sutbtilis subsp. Spizizenii CCM 1999, Bacillus thuringiensis CCM 19, and Priestia (Bacillus) megaterium CCM 2007) as well as G- (Citrobacter koseri CCM 2535, Enterobacter aerogenes CCM 2531, Escherichia coli CCM 3954). The range of maximal inhibition zones and MIC values was determined to be 4.67 to 8.33 mm and 3.49 to 7.71 mg.mL-1, respectively. Furthermore, B. thiriangensis, P. megaterium, and E. coli were all susceptible to the antimicrobial effects of the (STEO) on the fruit and vegetable model. According to research findings, STEO is a valuable source of organic chemicals that have the potential to be innovative antibacterial agents against microbes. [ABSTRACT FROM AUTHOR]

Iron (Fe) deficiency in calcareous soils is a significant agricultural challenge, affecting crop productivity and nutritional quality. This study aimed to isolate, characterize, and evaluate Fe solubilizing rhizobacterial isolates from maize rhizosphere in calcareous soils as potential biofertilizers. Forty bacterial isolates coded as SG1, SG2, ..., SG40 were isolated and screened for siderophore production, with ten showing significant Fe solubilizing capabilities. These isolates were further assessed for phosphate solubilization and exopolysaccharides production. The selected bacterial isolates were also screened under axenic conditions for their ability to improve maize growth. The isolates SG8, SG13, SG24, SG30 and SG33 significantly enhanced growth parameters of maize. Notably, SG30 showed highest increment in shoot length (58%), root length (54%), root fresh and dry biomass (67% and 76%), SPAD value (67%), relative water contents (69%), root surface area (61%), and Fe concentration in shoots (79%) as compared to control. The biochemical characterization of these strains showed that all these strains have capability to solubilize insoluble phosphorus, produce indole-3-acetic acid (IAA), and ammonia with catalase, urease and protease activity. Molecular identification through 16s rRNA gene sequencing confirmed high similarity (99.7–100%) of the selected isolates to various Bacillus species, including B. pyramidoids, B. firmicutes, and B. cereus. The study provides a strong base for developing eco-friendly, cost-effective biofertilizers to address Fe deficiency in crops and promote sustainable agriculture. [ABSTRACT FROM AUTHOR]

Prebiotic and probiotic combinations may lead to a synbiotic effect, demonstrating superior health benefits over either component alone. Using the Mucosal Simulator of the Human Intestinal Microbial Ecosystem (M-SHIME®) model, the effects of repeated supplementation with inulin (prebiotic, which is expected to provide a source of nutrition for the live microorganisms in the gut to potentially support optimal digestive health), Bacillus coagulans lactospore (probiotic), and a low and high dose of a synbiotic combination of the two on the gut microbial community activity and composition were evaluated. Test product supplementation increased the health-promoting short-chain fatty acids acetate and butyrate compared with levels recorded during the control period, demonstrating a stimulation of saccharolytic fermentation. This was likely the result of the increased abundance of several saccharolytic bacterial groups, including Megamonas, Bifidobacterium, and Faecalibacterium, following test product supplementation. The stimulation of acetate and butyrate production, as well as the increased abundance of saccharolytic bacterial groups were more evident in treatment week 3 compared with treatment week 1, demonstrating the value of repeated product administration. Further, the synbiotic formulations tended to result in greater changes compared with prebiotic or probiotic alone. Overall, the findings demonstrate a synbiotic potential for inulin and B. coagulans lactospore and support repeated administration of these products, indicating a potential for promoting gut health. [ABSTRACT FROM AUTHOR]

Grape powdery mildew (GPM) control is based on the preventive use of sulfur and curative application of synthetic fungicides, increasing the risk for producers' health and environmental and fruit contamination. This work aimed to select Bacillus strains isolated from the Brazilian tropical semi-arid region that are effective antagonists to GPM. In an initial screening performed by spraying bacterial suspensions in detached grape leaves, six strains of Bacillus spp. showed disease symptom reduction higher than 70.0%. Two greenhouse experiments showed that the bacterial strains LCB03, LCB28, and LCB30 showed control efficiency >80%, statistically similar to a commercial formulation with Bacillus amyloliquefaciens QST713. 16s rDNA sequencing showed that strain LCB03 showed 100.0% homology to B. velezensis, while LCB28 has high homology to B. tequillensis (99.93%), and LCB30 had 99.71% homology with B. siamensis. As an average for both greenhouse experiments, weekly application of Bacillus sp LCB03, Bacillus sp LCB28, and Bacillus sp. LCB30 reduced the average incidence by around 50% and more than 80% for GPM severity. [ABSTRACT FROM AUTHOR]

Bacterial wilt disease, caused by Ralstonia solanacearum poses a severe threat to ginger plants. The present study aimed to determine the effect of Bacillus strains to combat R. solanacearum-induced bacterial wilt in ginger by inducing defense enzymes viz., peroxidase(POX), Polyphenol oxidase (PPO), Phenylalanine ammonia-lyase (PAL) and total phenol content, while also promoting growth and yield. The Bacillus strains were isolated from soil samples collected from the Western Ghats, one of India's biological diversity hot spots through random sampling. Two strains exhibiting better antagonistic activity were identified as Bacillus spp through 16S rRNA sequencing. Pot studies were conducted to evaluate the biocontrol efficacy and plant growth promoting ability of these bacterial strains against R. solanacearum. Results showed that ginger plants treated with NIIST NB120 significantly increased shoot length 70.80 cm, leaf length 30.03 cm, leaf breadth 3.42 cm, number of leaves 22, and yield 355.81% compared to plants treated with R. solanacearum, which had lower values. Furthermore, plants treated with NIIST NB120 had the lowest bacterial wilt incidence at 25%, in contrast to 66% in plants treated with pathogen. Application of Bacillus strains also enhanced the activities of defense-related enzymes, including, PAL 0.030 units/ g tissue, PPO 0.0016 units/ g tissue, POD 68.28 units/ g tissue, and total phenolic content 219.5 units/ g tissue, with the lowest enzyme activity observed in pathogen treated plants. These findings suggest that the Bacillus strains NIIST B16 B. siamensis and NIIST NB120 B. amyloliquefaciens could be effective biocontrol agents of ginger bacterial wilt disease. [ABSTRACT FROM AUTHOR]

This study investigates the secretion pattern of extracellular polymeric substances (EPS) by Bacillus sp. under varying salt concentrations and elucidates the molecular mechanisms governing EPS synthesis and secretion. Salt stress inhibited cell proliferation, while optimal salt stimulation promoted EPS secretion, resulting in increased viscosity of the culture medium and the formation of bacterial clusters. Fourier infrared spectrum analysis revealed functional groups such as C-O-C and N-H within the EPS. Soluble-EPS (S-EPS) contained sulfur and phosphorus groups associated with heavy metal ions adsorption. The study also identified a novel polysaccharide formed through bonding EPS (B-EPS). High salt concentrations correlated with elevated levels of tryptophan protein and its derivatives, increased tyrosine polysaccharide derivatives, and decreased aromatic polysaccharides. B-EPS exhibited higher levels of aromatic polysaccharides, with Na+ promoting detachment of B-EPS from the cell surface. Transcriptome sequencing (RNA-seq) analysis under salt stress revealed significant expression of spore kinase (Kin D) and response regulatory protein Spo0 A in the phosphoric acid relay system. Key transcriptional regulatory factors, including Omp R and exopolysaccharide biosynthesis, were closely associated with EPS synthesis and secretion. This study establishes a theoretical foundation for the industrial production and practical application of EPS by elucidating the molecular mechanisms underlying Bacillus ' response to salt stress. [Display omitted] • Salt stress prompts early EPS secretion and enhances Bacillus survival. • Salt stress alters the composition of polysaccharide and protein content in EPS. • Kin D and Spo0 A pathways regulate EPS synthesis under salt stress. • Higher salt boost EPS secretion, elevating viscosity and forming larger aggregates. [ABSTRACT FROM AUTHOR]