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The most devastating soilborne disease of soybean is Phytophthora root rot (PRR) caused by Phytophthora sojae. Biological control has emerged as an effective method of reducing soilborne diseases. The present study isolated the bacterial strain W82T‐44 from the rhizosphere soil of a resistant soybean variety Williams 82. This strain was identified as Bacillus amyloliquefaciens and exhibited a 92.4% inhibition of mycelial growth of P. sojae. W82T‐44 produced cellulase, siderophore and protease and significantly promoted soybean growth. W82T‐44 treatment, compared to the negative control, was found to significantly (p < 0.05) increase soybean plant height (22.34 vs. 18.47 cm), fresh weight of the whole plant (2.57 vs. 2.05 g), dry weight (0.43 vs. 0.32 g), total root length (266.80 vs. 182.53 cm), root area (27.10 vs. 17.84 cm2) and root volume (1.88 vs. 1.16 cm3). The fermentation filtrate of W82T‐44 had significant inhibitory effects on mycelial growth, oospore formation and cyst germination in P. sojae and additionally promoted zoospore encystment. W82T‐44 possessed genes involved in lipopeptide synthesis, including bacilysin, surfactin, fengycin and bacillomycin. Moreover, it significantly upregulated pathogenesis‐related genes (β‐1,3‐glucanase, nonexpressor of pathogenesis‐related gene 1, chitinase) and genes encoding defence enzymes (polyphenol oxidase, phenylalanine ammonia‐lyase, peroxidase) in soybean roots (p < 0.05). The PRR disease index of soybean treated with the W82T‐44 strain was significantly lower (11.67) than the negative control (40.00; p < 0.05). The present study indicates the potential of B. amyloliquefaciens W82T‐44 as a biological control agent against PRR from various perspectives. [ABSTRACT FROM AUTHOR]

Background: Rusted root rot is one of the most common root diseases in Panax ginseng, and Cylindrocarpon destructans is one of the main pathogenic fungus. The objective of this study was to screen and explore the extracts of biocontrol bacteria isolated from ginseng rhizosphere soil against Cylindrocarpon destructans. Results: Bacterial strains Bacillus amyloliquefaciens YY8 and Enterobacteriacea YY115 were isolated and found to exhibit in vitro antifungal activity against C. destructans. A combination of crude protein extract from B. amyloliquefaciens YY8 and ethyl acetate extract from Enterobacteriacea YY115 in a 6:4 ratio exhibited the strongest antifungal activity against C. destructans. Measurements of electrical conductivity, protein content, and nucleic acid content in suspension cultures of C. destructans treated with a mixture extracts indicated that the extracts disrupted the cell membranes of rusted root rot mycelia, resulting in the leakage of electrolytes, proteins, and nucleic acids from the cells, and ultimately inhibiting the growth of C. destructans. The combined extracts suppressed the infection of ginseng roots discs by C. destructans effectively. Conclusion: The extracts obtained from the two bacterial strains effectively inhibited C. destructans in P. ginseng. It can provide scientific basis for the development of new biological control pesticides, reduce the use of chemical pesticides, and promote the sustainable development of agriculture. [ABSTRACT FROM AUTHOR]

This study was to investigate the therapeutic effect of Bacillus amyloliquefaciens (Ba) on atherosclerosis (AS). THP-1 monocyte was differentiated to THP-1 macrophage (THP-M) through phorbol 12-myristate 13-acetate. After pre-treatment by 108 cfu/ml Ba lasting 6 h, THP-M was induced with 100 mg/l ox-LDL lasting 48 h to form macrophage foam cell (THP-F). RT-qPCR and flow cytometry were employed to determine the polarization of THP-M and THP-F. ApoE−/− mice with high-fat and high-cholesterol diet were used for constructing an AS model to evaluate the effect of Ba on AS. Our in vitro results showed that Ba vegetative cells pre-treatment distinctly inhibited the levels of iNOS and CD16/CD32 (M1 macrophage markers), and increased the levels of FIZZ1, Ym1, Arg1, CD163, and CD206 (M2 macrophage markers), indicating that Ba pre-treatment promoted anti-inflammatory M2-like polarization both in THP-M and THP-F. Meanwhile, it also suppressed cholesterol uptake, esterification, and hydrolysis, and efflux by THP-M and THP-F. Additionally, our animal experiments demonstrated that Ba vegetative cells treatment suppressed high cholesterol, hyperglycemia, hyperlipidemia, and the release of inflammatory factors (TNF-α, IL-6 and IL-1β) in ApoE−/− AS mice. In a word, our results indicated that Ba may protect against AS through alleviating foam cell formation and macrophage polarization through targeting certain stages of AS. [ABSTRACT FROM AUTHOR]

Bacillus spp. are foodborne pathogens important in food contamination, especially in dried milk products. They are associated with foodborne outbreaks, spoilage of dairy products (sweet curdling and bitterness), and bovine mastitis. This study investigated the contamination rate of Bacillus spp. in a total of 105 samples of the dried milk products kishk, Cerelac and whole milk powder, marketed in Assiut city, Upper Egypt. The identification of the Bacillus spp. strains was completed using conventional biochemical methods and PCR protocols for the confirmation of isolates. Bacillus spp. were isolated from 57 out of 105 (54%) [95% CI: 44.6-64.0%] of the examined samples at levels of up to 7.7 log10 cfu/g. The prevalence of Bacillus spp. was significantly (P<0.05) higher in kishk (74%) than in the other food categories with a mean count of 4.04±0.49 log10 cfu/g. Regarding the species of Bacillus detected, 39.05% of the examined samples contained B. cereus, 8.57% contained B. subtilis, 2.86%: B. pumilus, another 2.86%: B. megatrium and 0.95%: B. licheniformis. B. cereus was isolated from 18 (51.43%) of the kishk samples, 9 (25.71%) of the Cerelac samples and 14 (40%) of the whole milk powder samples. Out of the 41 B. cereus strains previously identified by biochemical tests, 19 (46.34%) isolates were also confirmed using PCR (61.11%, 42.86% and 22.22% for kishk, whole milk powder and Cerelac, respectively). In conclusion, incorporating preventive measures to reduce bacterial contamination in the Egyptian dairy environment are warranted in order to avoid the contamination of milk products with these life-threatening pathogens. [ABSTRACT FROM AUTHOR]

Plants encounter many biotic entities, such as fungi, bacteria, and nematodes, which induce biotic stress that disrupts normal metabolism and limits the growth and productivity of plants. Currently, the use of plant growth-promoting bacterial endophytes instead of synthetic fungicides is intriguingly eco-friendly. An in vitro and in vivo antagonistic approach using Bacillus amyloliquefaciens RaSh1 was used to mimic the pathogenic effect of Alternaria alternata. The results showed that B. amyloliquefaciens significantly inhibited pathogenic fungal growth in vitro. Further, Capsicum annuum L. (pepper plants) were grown and subjected to inoculation with B. amyloliquefaciens and infected with A. alternata, and then the growth attributes, photosynthetic pigments, physio-biochemical parameters, and the level of endogenous phytohormones were assessed. Under the pathogen attack, the main responses, such as plant length, total fresh and dry weights, total chlorophylls, and pigments, were reduced, accompanied by increases in H2O2. As well, infection of pepper with A. alternata caused downregulation in the plant hormonal system by significantly decreasing gibberellins, indole-3-acetic acid, abscisic acid, as well as cytokinin concentrations. Although, with B. amyloliquefaciens application, an enhancement in growth, photosynthetic pigments, proline, thiol content, phenylalanine ammonia-lyase, and peroxidase in pepper plant leaves appeared while the content of H2O2 decreased. Endogenous phytohormones were found to be upregulated in B. amyloliquefaciens-inoculated and diseased plants. The current study found that B. amyloliquefaciens RaSh1 rescued pepper plant growth by modulating antioxidant defense and regulating hormones, and could be used to control A. alternata in an environmentally friendly manner while maintaining sustainable agriculture and food security. [ABSTRACT FROM AUTHOR]

Composting is an integral component of sustainable Municipal Solid Waste (MSW) management within the circular bio-economy platform. However, it faces challenges due to malodorous emissions that impact environmental and societal equilibrium. The present study aims to minimize odorous emissions and expedite compost maturation using a novel, efficient microbial consortium. Bacteria sourced from open dump sites in Sri Lanka were carefully screened based on concurrent enzyme production. Five developed consortia were tested for their performance in reducing malodors during the composting process of MSW. Consortium No. 5 (C5), comprised of Bacillus haynesii, Bacillus amyloliquefaciens, and Bacillus safensis, demonstrated outstanding performance with a significant (p < 0.05) reduction in odorous emissions. Additionally, consortium C5 exhibited impressive control over gas emissions, maintaining VOC, CH4, NH3, and H2S concentrations within ranges of 0.5-6 ppm, 0.5-0.8 ppm, 0.3-0.5 ppm, and 0.5-0.6 ppm, respectively, compared to control concentrations of 4.5-10.2 ppm, 0.5-5.5 ppm, 0.3-5.5 ppm, and 0.5-6.4 ppm, respectively. Additionally, comprehensive Electronic nose (E-nose) analysis substantiated C5's efficiency in attenuating Methane-Aliphatic compounds, Sulfur and Aromatic compounds, along with low-polarity aromatic and alkane compounds, all with statistical significance (p < 0.05). Further, the developed consortium could reduce the composting time from 110 ± 10 days to 17 ± 3 days, offering a sustainable solution for global MSW management. [ABSTRACT FROM AUTHOR]

Many notable applications have been described for magnetic nanoparticles in delivery of diverse drugs and bioactive compounds into cells, magnetofection for the treatment of cancer, photodynamic therapy, photothermal therapy, and magnetic particle imaging (MPI). In response to the growing demand for magnetic nanoparticles for drug delivery or biomedical imaging applications, more effective and eco-friendly methodologies are required for large-scale biosynthesis of this nanoparticles. The major challenge in the large-scale biomedical application of magnetic nanoparticles lies in its low efficiency and optimization of nanoparticle production can address this issue. In the current study, a prediction model is suggested by the fractional factorial designs. The present study aims to optimize culture media components for improved growth and iron uptake of this strain. The result of optimization for iron uptake by the strain ASFS1 is to increase the production of magnetic nanoparticles by this strain for biomedical applications in the future. In the present study, design of experiment method was used to probe the effects of some key medium components (yeast extract, tryptone, FeSO4, Na2-EDTA, and FeCl3) on Fe content in biomass and dried biomass of strain ASFS1. A 25−1 fractional factorial design showed that Na2-EDTA, FeCl3, yeast extract-tryptone interaction, and FeSO4-Na2-EDTA interaction were the most parameters on Fe content in biomass within the experimented levels (p < 0.05), while yeast extract, FeCl3, and yeast extract-tryptone interaction were the most significant factors within the experimented levels (p < 0.05) to effect on dried biomass of strain ASFS1. The optimum culture media components for the magnetic nanoparticles production by strain ASFS1 was reported to be 7.95 g L−1 of yeast extract, 5 g L−1 of tryptone, 75 μg mL−1 of FeSO4, 192.3 μg mL−1 of Na2-EDTA and 150 μg mL−1 of FeCl3 which was theoretically able to produce Fe content in biomass (158 μg mL−1) and dried biomass (2.59 mg mL−1) based on the obtained for medium optimization. Using these culture media components an experimental maximum Fe content in biomass (139 ± 13 μg mL−1) and dried biomass (2.2 ± 0.2 mg mL−1) was obtained, confirming the efficiency of the used method. [ABSTRACT FROM AUTHOR]

This study used the DNA of Bacillus amyloliquefaciens Ba168 as a template to amplify the flagellin BP8-2 gene and ligate it into the fusion expression vector pCAMBIA1300-35S-EGFP after digestion for the construction of the expression vector pCAMBIA1300-EGFP-BP8-2. Next, using Nicotiana benthamiana as receptor material, transient expression was carried out under the mediation of Agrobacterium tumefaciens C58C1. Finally, the transient expression and subcellular localisation of flagellin BP8-2 protein were analysed using the imaging of co-transformed GFP under laser confocal microscopy. The results showed that flagellin BP8-2 was localised in the cell membrane and nucleus, and the RT-PCR results showed that the BP8-2 gene could be stably expressed in tobacco leaf cells. Furthermore, there was stronger antiviral activity against tobacco mosaic virus (TMV) infection in Nicotiana glutinosa than in BP8-2 and ningnanmycin, with an inhibitory effect of 75.91%, protective effect of 77.45%, and curative effect of 68.15%. TMV movement and coat protein expression were suppressed, and there was a high expression of PR-1a, PAL, and NPR1 in BP8-2-treated tobacco leaf. These results suggest that flagellin BP8-2 inhibits TMV by inducing resistance. Moreover, BP8-2 has low toxicity and is easily biodegradable and eco-friendly. These results further enrich our understanding of the antiviral mechanisms of proteins and provide alternatives for controlling viral diseases in agriculture. [ABSTRACT FROM AUTHOR]

The causal agent of tomato leaf mold, Cladosporium fulvum, is prevalent in greenhouses worldwide, especially under high humidity conditions. Despite its economic impact, studies on antifungal agents targeting C. fulvum remain limited. This study evaluates biocontrol agents (BCAs) as alternatives to chemical controls for managing this disease, alongside the strobilurin fungicide azoxystrobin. From a Moroccan collection of potential BCAs, five bacterial isolates (Alcaligenes faecalis ACBC1, Pantoea agglomerans ACBC2, ACBP1, ACBP2, and Bacillus amyloliquefaciens SF14) and three fungal isolates (Trichoderma spp. OT1, AT2, and BT3) were selected and tested. The in vitro results demonstrated that P. agglomerans isolates reduced mycelial growth by over 60% at 12 days post-inoculation (dpi), while Trichoderma isolates achieved 100% inhibition in just 5 dpi. All bacterial isolates produced volatile organic compounds (VOCs) with mycelial inhibition rates ranging from 38.8% to 57.4%. Likewise, bacterial cell-free filtrates significantly inhibited the pathogen's mycelial growth. Greenhouse tests validated these findings, showing that all the tested isolates were effective in reducing disease incidence and severity. Azoxystrobin effectively impeded C. fulvum growth, particularly in protective treatments. Fourier transform infrared spectroscopy (FTIR) analysis revealed significant biochemical changes in the treated plants, indicating fungal activity. This study provides valuable insights into the efficacy of these BCAs and azoxystrobin, contributing to integrated management strategies for tomato leaf mold disease. [ABSTRACT FROM AUTHOR]

This study evaluates the biocontrol efficacy of three bacterial strains (Pseudomonas fluorescens DTPF-3, Bacillus amyloliquefaciens DTBA-11, and Bacillus subtilis DTBS-5) and two fungal strains (Trichoderma harzianum Pusa-5SD and Aspergillus niger An-27) antagonists, along with their combinations at varying doses (5.0, 7.5, and 10.0 g/kg of seeds), against wheat powdery mildew. The most effective dose (10 g/kg seeds) was further analyzed for its impact on induced resistance and plant growth promotion under greenhouse conditions. The study measured defense enzyme activities, biochemical changes, and post-infection plant growth metrics. All tested microbial antagonists at 10 g/kg significantly reduced PM severity, with B. subtilis strain DTBS-5 outperforming others in reducing PM severity and achieving the highest biocontrol efficacy. It was followed by B. amyloliquefaciens strain DTBA-11 and P. fluorescens strain DTPF-3, with the fungal antagonists showing no significant effect. Wheat crops treated with B. subtilis strain DTBS-5 exhibited substantial increases in defense-related enzyme activities and biochemicals, suggesting an induced resistance mechanism. The study found a 45% increase in peroxidase (POD) activity, a 50% increase in catalase (CAT) activity, a 30% increase in phenolic content, and a 25% increase in soluble protein content in the wheat plants treated with microbial antagonists. The study highlights the effectiveness of microbial antagonists, particularly B. subtilis strain DTBS-5, in managing wheat PM through biocontrol, induced resistance, and enhanced plant growth, offering a sustainable alternative to chemical treatments. [ABSTRACT FROM AUTHOR]

Paraprobiotics, non-viable versions of probiotic microorganisms, offer a promising prophylactic strategy in aquaculture, addressing concerns about the safety and functionality of probiotics while harnessing similar health benefits for fish and shellfish. This study determined the dietary effects of paraprobiotic preparation from Bacillus amyloliquefaciens COFCAU_P1 to support the immune system and control Aeromonas hydrophila infection in Labeo rohita fingerlings. Paraprobiotic was prepared by heat and formalin inactivation of the probiotic B. amyloliquefaciens and subsequently analyzed by scanning electron microscopy. The cellular immunological responses viz. superoxide anion, myeloperoxidase activity, nitric oxide production, and leucocyte proliferation of rohu head-kidney (HK) leucocytes increased significantly with different doses (106, 107, and 108 cells ml−1) of both heat and formalin-inactivated preparations in vitro. Both preparations significantly enhanced the in vitro immune gene (IL-1β and IFN-γ) expression, indicating their immunostimulatory response at the molecular level. As the formalin-inactivated preparation showed a better immune response, it was selected for the subsequent in vivo experiment. Dietary administration of formalin-inactivated B. amyloliquefaciens at different doses (106, 107, and 108 cells g−1 feed) showed significantly higher responses in innate immune (respiratory burst, myeloperoxidase, and anti-protease activity) and biochemical parameters (total protein, albumin, globulin alkaline phosphatase activity, and glucose content). Resistance against experimental A. hydrophila infection was increased significantly after 30 days of feeding of the formalin-inactivated B. amyloliquefaciens. At the paraprobiotic dose of 1 × 108 cells g−1 feed, the maximum immune response and survivability against A. hydrophila infection were observed. It can be inferred from the results that formalin-inactivated B. amyloliquefaciens paraprobiotic can be used as a promising immunostimulant in aquaculture. The potency of B. amyloliquefaciens paraprobiotic to enhance immunity and survivability of rohu against experimental A. hydrophila infection is worth mentioning. [ABSTRACT FROM AUTHOR]

Drought stress is one of the major impediments to plant growth. Plant growth-promoting rhizobacteria (PGPR) can mitigate moisture stress in plants by increasing the ability of plant nutrient uptake and transport. In this study, we investigated the root phenotype, mineral nutrients (in leaves, roots, and soil), soil pH, water saturation deficit (WSD), free water content (FWC), and bound water content (BWC) of leaves of two alfalfa varieties, 'Galalxie Max' (drought-tolerant) and 'Saidi 7' (drought-sensitive), in the presence or absence of Bacillus amyloliquefaciens QST713 under drought stress conditions. The results showed that water stress negatively affected both cultivar root morphology (total root length, average diameter, total surface area, and volume) and the contents of K and Fe in leaves, roots, and soil. It also reduced the Mn and Zn contents in the soil while increasing the content of Na in the leaves and soil. Additionally, alfalfa plants under drought stress exhibited higher levels of soil pH, WSD, and BWC but lower contents of FWC and ratios of BWC/FWC in the leaves of both cultivars. However, QST713 application significantly enhanced the total root length, average root diameter, and the contents of K and Fe in alfalfa leaves, roots, and soil, as well as the BWC/FWC ratio in leaves under drought stress conditions. A significant reduction in the Na content was detected in QST713-treated alfalfa leaves and soil under drought stress. Furthermore, QST713 application noticeably decreased soil pH and WSD. The current findings showed that QST713 enhanced the water stress tolerance of alfalfa plants by ameliorating root morphology, reducing soil pH, and improving the BWC/FWC ratio, consequently promoting the accumulation of mineral nutrients (mainly K and Fe). Overall, Bacillus amyloliquefaciens QST713 can serve as a potential green fertilizer in sustainable agriculture to improve soil nutrients and enhance plant production under increasing drought conditions. [ABSTRACT FROM AUTHOR]

We established confrontations between two different fungi, i.e., the maize anthracnose and stalk rot pathogen Colletotrichum graminicola, and the ubiquitous fungus Aspergillus nidulans, and different biocontrol species, i.e., Bacillus subtilis, Bacillus velezensis, and Bacillus amyloliquefaciens. In all fungus–bacterium confrontations tested, growth arrest and, thus, distance inhibition was observed on solid substrata. LC–MS/MS analyses of culture filtrates suggested formation of several metabolites only synthesized in confrontations. Interestingly, microscopy of fungal hyphae grown in liquid medium showed protrusions and color changes occurred only in media harboring fungus-bacterium confrontations. These observations indicate metabolic re-programming and suggest formation of putative secondary metabolites in interactions involving microbial biocontrol agents. [ABSTRACT FROM AUTHOR]

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The most serious problems for cultivated grapes are pathogenic microorganisms, which reduce the yield and quality of fruit. One of the most widespread disease of grapes is "gray mold", caused by the fungus Botrytis cinerea. Some strains of Bacillus, such as Bacillus halotolerans, Bacillus amyloliquefaciens, and Bacillus velezensis, are known to be active against major post-harvest plant rots. In this study, we showed that the endophytic bacteria B. velezensis strain AMR25 isolated from the leaves of wild grapes Vitis amurensis Rupr. exhibited antimicrobial activity against grape pathogens, including B. cinerea. The genome of B. velezensis AMR25 has one circular chromosome with a length of 3,909,646 bp. with 3689 open reading frames. Genomic analysis identified ten gene clusters involved in the nonribosomal synthesis of polyketides (macrolactin, bacillene, and difficidin), lipopeptides (surfactin, fengycin, and bacillizin), and bacteriocins (difficidin). Also, the genome under study contains a number of genes involved in root colonization, biofilm formation, and biosynthesis of phytohormones. Thus, the endophytic bacteria B. velezensis strain AMR25 shows great promise in developing innovative biological products for enhancing plant resistance against various pathogens. [ABSTRACT FROM AUTHOR]

Background: Fungal toxins are highly toxic and widely distributed, presenting a considerable threat to global agricultural development. Addressing the issue of aflatoxin B1 (AFB1) contamination in feed, it is crucial to ascertain the effectiveness and mechanisms of microbial strains in degradation. Results: This study used isotope tracing and nuclear magnetic resonance (NMR) to investigate the degradation products of Bacillus amyloliquefaciens YUAD7 in complex substrates. By tracing 14C34-AFB1 and utilizing NMR, ultra-performance liquid chromatography–quadrupole time-of-flight/mass spectrometry (UPLC–Q-TOF/MS) purification and identification techniques, it was confirmed that AFB1 was degraded by YUAD7 into C12H14O4, C5H12N2O2, C10H14O2, and C4H12N2O, effectively removing 99.7% of AFB1 (100 μg/kg) from alfalfa silage. YUAD7 targeted the ester bond in the vanillin lactone ring structure, the ether bond in the furan ring structure, and the unsaturated carbon–carbon double bond in the furan ring structure during AFB1 degradation, disrupting the toxic sites responsible for AFB1's carcinogenic, teratogenic, and mutagenic effects and achieving biodegradation. Moreover, B. amyloliquefaciens YUAD7 transformed AFB1 through processes like hydrogenation, enzyme modification, and the loss of the -CO group while also being associated with metabolic pathways such as alanine, aspartate, glutamate metabolism, glutathione metabolism, cysteine and methionine metabolism, and pentose and glucuronate interconversions. Conclusions: The utilization of isotope tracing allowed for rapid identification of degradation products in complex substrates, while NMR elucidated the structures of these products. This deepens our understanding of AFB1 biodegradation mechanisms, providing technical support for the practical application of these bacteria in degradation, and new insights into studying the biological degradation mechanism. B. amyloliquefaciens YUAD7 can be used as a potential strain for degrading AFB1 in large-scale silage. [ABSTRACT FROM AUTHOR]

This study aimed to explore the effects of Bacillus amyloliquefaciens GSBa-1 treatment on anthracnose disease resistance and the metabolism of reactive oxygen species (ROS) and phenylpropanoids in mangoes during storage. Mangoes were soaked in a solution containing 1 × 108 CFU/mL of B. amyloliquefaciens GSBa-1. The anthracnose disease incidence, disease index, respiration intensity, ethylene release, reactive oxygen species content, and the activities of related metabolic enzymes, phenylpropanoid-related metabolic enzymes, and phenolic acids in the skin and pulp of mangoes were investigated under normal temperature storage conditions. The results showed that the antagonistic bacterial treatment (ABT) did not significantly inhibit the growth of Colletotrichum gloeosporioides in vitro. However, it significantly reduced the incidence of mango anthracnose disease when applied to the mango peel. ABT enhanced the latent resistance of mango to anthracnose disease by activating its reactive oxygen and phenylpropanoid metabolism. It maintained higher levels of ROS production and elimination in the peel. Moreover, it rapidly activated manganese superoxide dismutase, induced the accumulation of H2O2, and enhanced the activity of manganese superoxide dismutase, catalase, ascorbate peroxidase, and peroxidase in the mango peel. Furthermore, ABT activated phenylalanine ammonia-lyase, cinnamic acid-4-hydroxylase, 4-coumaroyl-CoA ligase, and cinnamyl alcohol dehydrogenase in the mango peel and pulp, promoting the accumulation of antifungal phenolic acids such as gallic acid, catechins, and ellagic acid. Bacillus amyloliquefaciens GSBa-1 may be a potent inhibitor of mango anthracnose, primarily enhancing the resistance of mangoes to anthracnose by synergistically activating ROS in the peel and phenylpropanoid metabolism in the pulp, thereby reducing the incidence of anthracnose effectively. [ABSTRACT FROM AUTHOR]

Background: Selenium nanoparticles (SeNPs) are increasingly gaining attention due to its characteristics of low toxicity, high activity, and stability. Additionally, Bacillus licheniformis, as a probiotic, has achieved remarkable research outcomes in diverse fields such as medicine, feed processing, and pesticides, attracting widespread attention. Consequently, evaluating the activity of probiotics and SeNPs is paramount. The utilization of probiotics to synthesize SeNPs, achieving large-scale industrialization, is a current hotspot in the field of SeNPs synthesis and is currently the most promising synthetic method. To minimize production costs and maximize yield of SeNPs, this study selected agricultural by-products that are nutrient-rich, cost-effective, and readily available as culture medium components. This approach not only fulfills industrial production requirements but also mitigates the impact on downstream processes. Results: The experimental findings revealed that SeNPs synthesized by B. licheniformis F1 exhibited a spherical morphology with diameters ranging from 110 to 170 nm and demonstrating high stability. Both the secondary metabolites of B. licheniformis F1 and the synthesized SeNPs possessed significant free radical scavenging ability. To provide a more robust foundation for acquiring large quantities of SeNPs via fermentation with B. licheniformis F1, key factors were identified through single-factor experiments and response surface methodology (RSM) include a 2% seed liquid inoculum, a temperature of 37 ℃, and agitation at 180 rpm. Additionally, critical factors during the optimization process were corn powder (11.18 g/L), soybean meal (10.34 g/L), and NaCl (10.68 g/L). Upon validating the optimized conditions and culture medium, B. licheniformis F1 can synthesize nearly 100.00% SeNPs from 5 mmol/L sodium selenite. Subsequently, pilot-scale verification in a 5 L fermentor using the optimized medium resulted in a shortened fermentation time, significantly reducing production costs. Conclusion: In this study, the efficient production of SeNPs by the probiotic B. licheniformis F1 was successfully achieved, leading to a significant reduction in fermentation costs. The exploration of the practical applications of this strain holds significant potential and provides valuable guidance for facilitating the industrial-scale implementation of microbial synthesis of SeNPs. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Food Safety & Quality is the property of Journal of Food Safety & Quality Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Bacillus atrophaeus HAB-5 is a plant growth-promoting rhizobacterium (PGPR) that exhibits several biotechnological traits, such as enhancing plant growth, colonizing the rhizosphere, and engaging in biocontrol activities. In this study, we conducted whole-genome sequencing of B. atrophaeus HAB-5 using the single-molecule real-time (SMRT) sequencing platform by Pacific Biosciences (PacBio; United States), which has a circular chromosome with a total length of 4,083,597 bp and a G + C content of 44.21%. The comparative genomic analysis of B. atrophaeus HAB-5 with other strains, Bacillus amyloliquefaciens DSM7, B. atrophaeus SRCM101359, Bacillus velezensis FZB42, B. velezensis HAB-2, and Bacillus subtilis 168, revealed that these strains share 2,465 CDSs, while 599 CDSs are exclusive to the B. atrophaeus HAB-5 strain. Many gene clusters in the B. atrophaeus HAB-5 genome are associated with the production of antimicrobial lipopeptides and polypeptides. These gene clusters comprise distinct enzymes that encode three NRPs, two Transat-Pks, one terpene, one lanthipeptide, one T3PKS, one Ripp, and one thiopeptide. In addition to the likely IAA-producing genes (trpA, trpB, trpC, trpD, trpE, trpS, ywkB, miaA, and nadE), there are probable genes that produce volatile chemicals (acoA, acoB, acoR, acuB, and acuC). Moreover, HAB-5 contained genes linked to iron transportation (fbpA, fetB, feuC, feuB, feuA, and fecD), sulfur metabolism (cysC, sat, cysK, cysS, and sulP), phosphorus solubilization (ispH, pstA, pstC, pstS, pstB, gltP, and phoH), and nitrogen fixation (nif3-like, gltP, gltX, glnR, glnA, nadR, nirB, nirD, nasD, narl, narH, narJ, and nark). In conclusion, this study provides a comprehensive genomic analysis of B. atrophaeus HAB-5, pinpointing the genes and genomic regions linked to the antimicrobial properties of the strain. These findings advance our knowledge of the genetic basis of the antimicrobial properties of B. atrophaeus and imply that HAB-5 may employ a variety of commercial biopesticides and biofertilizers as a substitute strategy to increase agricultural output and manage a variety of plant diseases. [ABSTRACT FROM AUTHOR]

The current study attempted to develop a bacterial consortium which can degrade chlorpyrifos pesticide efficiently. Five morphologically different bacterial strains, capable to tolerate high chlorpyrifos concentration, were isolated from pesticide-contaminated soil. Further, possible combinations of the isolates were formed and each combination was screened and chlorpyrifos degradation percentage and half-lives were calculated. The consortium CON11, comprising of four isolates (CP28, CP30, CP31, and CP34) showed the highest chlorpyrifos degradation. The individual independent variables of chlorpyrifos degradation by CON11 viz. temperature (°C), pH, incubation time (days) and pesticide concentration (ppm) were optimized using one-factor at-a-time experiments. The consortium isolates were then identified by the molecular tools 16S rRNA gene typing and the sequences were submitted to GenBank. The four bacterial isolates thus identified are Bacillus amyloliquefaciens CP28 (MH667455), Bacillus pumilus CP30 (MH667456), Bacillus marisflavi CP31 (MN715880), and Bacillus subtilis CP34 (MH667458). These isolates which comprise CON11 consortium could degrade 91% of 100 ppm chlorpyrifos after 6 days of incubation at 30 °C and pH 7 with a half-life of 1.73 days indicating the promising potential of the consortium, CON11, in the cleanup of chlorpyrifos contaminated sites. [ABSTRACT FROM AUTHOR]

Background: In this study, we isolated a cellulase-producing bacterium, Bacillus amyloliquefaciens strain elh, from rice peel. We employed two optimization methods to enhance the yield of cellulase. Firstly, we utilized a one-variable-at-a-time (OVAT) approach to evaluate the impact of individual physical and chemical parameters. Subsequently, we employed response surface methodology (RSM) to investigate the interactions among these factors. We heterologously expressed the cellulase encoding gene using a cloning vectorin E. coli DH5α. Moreover, we conducted in silico molecular docking analysis to analyze the interaction between cellulase and carboxymethyl cellulose as a substrate. Results: The bacterial isolate eh1 exhibited an initial cellulase activity of 0.141 ± 0.077 U/ml when cultured in a specific medium, namely Basic Liquid Media (BLM), with rice peel as a substrate. This strain was identified as Bacillus amyloliquefaciens strain elh1 through 16S rRNA sequencing, assigned the accession number OR920278 in GenBank. The optimal incubation time was found to be 72 h of fermentation. Urea was identified as the most suitable nitrogen source, and dextrose as the optimal sugar, resulting in a production increase to 5.04 ± 0.120 U/ml. The peak activity of cellulase reached 14.04 ± 0.42 U/ml utilizing statistical optimization using Response Surface Methodology (RSM). This process comprised an initial screening utilizing the Plackett–Burman design and further refinement employing the BOX -Behnken Design. The gene responsible for cellulase production, egl, was effectively cloned and expressed in E. coli DH5α. The transformed cells exhibited a cellulase activity of 22.3 ± 0.24 U/ml. The egl gene sequence was deposited in GenBank with the accession number PP194445. In silico molecular docking revealed that the two hydroxyl groups of carboxymethyl cellulose bind to the residues of Glu169 inside the binding pocket of the CMCase. This interaction forms two hydrogen bonds, with an affinity score of −5.71. Conclusions: Optimization of cultural conditions significantly enhances the yield of cellulase enzyme when compared to unoptimized culturing conditions. Additionally, heterologous expression of egl gene showed that the recombinant form of the cellulase is active and that a valid expression system can contribute to a better yield of the enzyme. [ABSTRACT FROM AUTHOR]

To obtain effective biocontrol strains for downy mildew of grape, 38 endophytic bacteria were isolated from fruits, seeds, and old stems of six grape varieties. Using spot inoculation mixtures of sporangial suspensions of Plasmopara viticola and biocontrol bacterial suspension, this screen yielded three strains (G1, G5, and G9) with good antagonistic effects against P. viticola. The growth inhibition rate was 100%, which was comparable to the effect of the positive control Bacillus subtilis strain CN181. The enzyme activity and the metabolites of strain G1 were examined on casein hydrolysate medium, sodium carboxymethyl cellulose agar plates, and chrome azurol sulfonate (CAS) agar plates. The antifungal protein component was identified by liquid chromatography–mass spectrometry (LC–MS). The results showed that strain G1 was more effective against Plasmopara viticola after two field trials, and the inhibition rates of strain G1 on the seventh day of the two field trials were 47.5% and 36.9%, respectively. Strain G1 was identified as Bacillus amyloliquefaciens based on morphological examination and 16S rDNA sequence analysis. It produced proteases, cellulases, and siderophores. Crude protein of the strain mainly included the putative segregation protein SpoVG, which inhibited P. viticola. [ABSTRACT FROM AUTHOR]

An eight-week feeding trial investigated the effects of fishmeal (FM) replacement by soybean meal (SBM) and poultry by-product meal (PBM) in diets supplemented with two methionine sources (DL-Met and AQUAVI®) and their combinations with ECOBIOL®(Bacillus amyloliquefaciens CECT 5940) on growth performance, body composition, and nutrient metabolism of Penaeus vannamei. Four hundred shrimp (0.30 ± 0.04 g) randomly distributed into 20 tanks (20 shrimp tank-1 ) were fed with five experimental diets (four repetitions per diet). A control diet (CD; 20% FM) and four diets with 50% FM replacement supplemented with different methionine sources and ECOBIOL®combinations: D1 (0.13% DL-MET), D2 (0.06% AQUAVI®), D3 (0.13% DL-MET plus 0.10% ECOBIOL®), and D4 (0.06% AQUAVI®plus 0.10% ECOBIOL® ). Shrimp fed D2 and D4 had better growth performance, nutrient utilization, and body composition. Shrimp fed D3 also had good growth performance but higher lipid body composition. Shrimp fed D1 had the worst growth performance, nutrient utilization, and body composition values. Nutrient metabolism-related genes were affected by dietary treatments. Protein synthesis-related genes decreased mostly in shrimp fed D1 and D2 while increased mostly in shrimp fed D3 and D4, lipolysis-related genes had a better transcriptional response in shrimp fed D4 and lipogenesis-related genes were mostly downregulated in shrimp fed D2 while were mostly upregulated in shrimp fed D3 and D4. Results suggested that FM could be partially replaced with SBM and PBM in shrimp feeds supplemented with 0.06% AQUAVI®alone or combined with 0.10% ECOBIOL®without adversely affecting the growth and nutrient metabolism of P. vannamei. [ABSTRACT FROM AUTHOR]

The food enzyme glutaminase (l‐glutamine amidohydrolase; EC 3.5.1.2) is produced with the non‐genetically modified Bacillus amyloliquefaciens strain AE‐GT by Amano Enzyme Inc. A safety evaluation of this food enzyme was made previously, in which EFSA concluded that this food enzyme did not give rise to safety concerns when used in five food manufacturing processes. Subsequently, the applicant requested to extend its use to thirteen additional processes and to revise the use levels. In this assessment, EFSA updated the safety evaluation of this food enzyme when used in a total of eighteen food manufacturing processes. As the food enzyme–total organic solids (TOS) are removed from the final foods in two food manufacturing processes, the dietary exposure to the food enzyme–TOS was estimated only for the remaining sixteen processes. Dietary exposure was calculated to be up to 0.678 mg TOS/kg body weight per day in European populations. Based on the data provided for the previous evaluation and the revised dietary exposure in the present evaluation, the Panel concluded that this food enzyme does not give rise to safety concerns under the revised intended conditions of use. [ABSTRACT FROM AUTHOR]

The food enzyme bacillolysin (EC 3.4.24.28) is produced with the non‐genetically modified Bacillus amyloliquefaciens strain AE‐NP by Amano Enzyme Inc. A safety evaluation of this food enzyme was made previously, in which EFSA concluded that this food enzyme did not give rise to safety concerns when used in thirteen food manufacturing processes. Subsequently, the applicant requested to extend its use to two additional processes. In this assessment, EFSA updated the safety evaluation of this food enzyme when used in a total of fifteen food manufacturing processes. As the food enzyme–total organic solids (TOS) are removed in two food manufacturing processes, the dietary exposure to the food enzyme–TOS was estimated only for the remaining thirteen processes. Dietary exposure was calculated to be up to 35.251 mg TOS/kg body weight per day in European populations. Based on the data provided for the previous evaluation and the revised dietary exposure in the present evaluation, the Panel concluded that this food enzyme does not give rise to safety concerns under the revised intended conditions of use. [ABSTRACT FROM AUTHOR]

The biomass filtrate of the endophytic bacterial strain Bacillus amyloliquefaciens Fa.2 was utilized for the eco-friendly production of silver nanoparticles (Ag-NPs). The yellowish-brown color's optical properties showed a maximum surface plasmon resonance at 415 nm. The morphological and elemental composition analysis reveals the formation of spherical shapes with sizes of 5–40 nm, and the Ag ion comprises the major component of the produced Ag-NPs. X-ray diffraction confirmed the crystalline structure, whereas dynamic light scattering reveals the high stability of synthesized Ag-NPs with a polydispersity index of 0.413 and a negative zeta potential value. The photocatalytic experiment showed the efficacy of Ag-NPs to degrade methylene blue with maximum percentages of 73.9 ± 0.5 and 87.4 ± 0.9% under sunshine and UV irradiation, respectively, compared with 39.8% under dark conditions after 210 min. Additionally, the reusability of Ag-NPs was still more active for the fifth run, with a percentage decrease of 11.6% compared with the first run. Interestingly, the biogenic Ag-NPs showed superior antimicrobial activity against different pathogenic Gram-negative bacteria (MIC = 6.25 µg mL−1), Gram-positive bacteria (MIC = 12.5 µg mL−1), and uni- and multicellular fungi (MIC = 12.5 µg mL−1). Moreover, the biosynthesized Ag-NPs could target cancer cells (Pc3 and Mcf7) at low concentrations compared with normal cell (Vero) lines. The IC50 of normal cells is 383.7 ± 4.1 µg mL−1 compared with IC50 Pc3 (2.5 ± 3.5 µg mL−1) and McF7 (156.1 ± 6.8 µg mL−1). Overall, the bacterially synthesized Ag-NPs showed multifunctional features to be used in environmental catalysis and biomedical applications. [ABSTRACT FROM AUTHOR]

Edible seaweed - Caulerpa lentillifera is being cultivated along the coast of Khanh Hoa province, Vietnam, and makes a relatively large contribution to the economic development of this region. Bacterial strains originating from marine sources such as those associated with seaweed and hard coral were screened for properties of promote plant growth with the capacity of indole-3-acetic acid (IAA) - a phytohormone belonging to auxin group, the phosphate solubilization ability and antibacterial activity of IAA-producing strains were also performed in this study. Robust strains were identified by morphological methods with biochemical tests and analysis of 16s RNA sequences. Isolate RN06 produced high amounts of IAA, utilized inorganic phosphate, and inhibited Bacillus subtilis ATCC6633, Escherichia coli 0157, and Serratia marcescens PDL100. The IAA producer HRA5 isolated from hard coral demonstrated the ability to solubilize phosphate and exhibited antibacterial activity against B. subtilis. Morphological analysis and 16sRNA sequencing showed that isolate RN06 was the closest strain to Bacillus amyloliquefaciens and HRA5 was linked to Pseudomonas sp. This is the first report of isolated bacteria from seaweed and corals from the Vietnamese sea served as potential strains for further research of the application of biological inoculants specifically for seaweed farming. [ABSTRACT FROM AUTHOR]

The significance of microorganisms occurring in foods is predominantly targeted due to their application for identifying a novel range of the bacterial spectrum. Diverse microbial species are capable of exhibiting potential pharmacological activities like antimicrobial and anticancer. Microbial strains capable of reducing obesity-related syndromes have also been reported. In the present study, the hypocholesterolemic efficacy of Bacillus amyloliquefaciens isolated from dairy products was scrutinised by in vitro (3T3-L1 adipose cells) and in vivo (high-fat diet-induced obese Wistar albino rats) methods. Potential cholesterol-lowering isolates were screened using a plate assay method and optimised by physical parameters. Molecular identification of the topmost five cholesterol-lowering isolates was acquired by amplification of the 16 S rRNA gene region. Bacillus amyloliquefaciens strain KAVK1, followed by strains KAVK2, KAVK3, KAVK4, and KAVK5 were molecularly determined. Further, cholesterol-lowering strains degraded the spectral patterns determined by the side chain of a cholesterol molecule. The anti-lipase activity was demonstrated using the porcine pancreatic lipase inhibitory method and compared with the reference compound Atorvastatin. Lyophilised strain KAVK1 revealed maximum pancreatic lipase inhibition. Strain KAVK1 attenuated lipid accumulation in 3T3-L1 adipose cell line predicted by Oil Red O staining method. Significant reduction of body weight and change in lipid profile was recognised after the supplement of KAVK1 to obese rats. Histopathological changes in organs were predominantly marked. The result of this study implies that the cholesterol-lowering B. amyloliquefaciens KAVK1 strain was used to treat hypercholesterolemia. [ABSTRACT FROM AUTHOR]

Copyright of Acta Agriculturae Slovenica is the property of Biotechnical Faculty of the University of Ljubljana and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Amazake is a traditional, sweet, non-alcoholic Japanese beverage typically produced through koji fermentation by the fungus Aspergillus oryzae. However, alternative microorganisms such as Bacillus amyloliquefaciens offer potential advantages and novel possibilities for producing similar fermented beverages. This study aimed to replicate the ancestral beverage of amazake by replacing A. oryzae (W-20) with B. amyloliquefaciens (NCIMB 12077) and comparing their fermentation processes and resulting products. Our results show that the production of amazake with B. amyloliquefaciens (ABA) is not only possible but also results in a beverage that is otherwise distinct from traditional amazake (AAO). Saccharification was achievable in ABA at higher temperatures than in AAO, albeit with lower reducing sugar and enzymatic activity values. Amino acids and organic acids were more abundant in AAO, with cysteine being uniquely present in AAO and shikimic acid only being present in ABA. The volatile aroma compound profiles differed between the two beverages, with AAO exhibiting a greater abundance of aldehydes, and ABA a greater abundance of ketones and alcohols. Interestingly, despite these compositional differences, the two beverages showed similar consumer panel acceptance rates. An analysis of their microbial communities revealed pronounced differences between the amazakes, as well as temporal changes in ABA but not in AAO. This study provides promising insights into harnessing the potential of B. amyloliquefaciens as the primary microorganism in the fermentation process of amazake-like beverages, marking an important advancement in the field of fermented low-alcohol beverage production, with possible applications in other fermented foods. [ABSTRACT FROM AUTHOR]

Spray drying was used to prepare the bacterial powder of Bacillus amyloliquefaciens, which was then used for wettable reagent production. The biocontrol effects of the microbial agent B. amyloliquefaciens against Botrytis cinerea on tomatoes were studied for pre- and postharvest applications. Single-factor analysis was performed to optimize the factors that may affect the bacterial concentration during spray drying, including inlet temperature, feed rate, airflow rate, wall materials, and their concentrations. The parameters were established as follows: inlet temperature of 170 °C, feed flow rate of 360 mL/h, airflow rate of 30 m3/h, and 10% maltodextrin. The agent with a concentration of 11.30 log colony-forming units (cfu)/g was obtained. The prepared wettable bacterial powder showed significant inhibitory activities against the tested pathogenic fungi, including Fusarium oxysporum, Alternaria alternata, Aspergillus niger, and B. cinerea. After harvest, the tomatoes were sprayed with the prepared microbial agent. The bacterial spores colonized the surface of tomatoes, which prevented B. cinerea from infecting the tomatoes effectively by competition for space and parasitism. The preharvest tomatoes were sprayed with the prepared microbial agent at a dose of 8.1 × 107 cfu/mL, which showed an equivalent biocontrol effect to procymidone. Preharvest spray could prolong the storage period and reduce the rotting rate of tomatoes during storage. In conclusion, an efficient and stable B. amyloliquefaciens agent can be prepared by spray drying, which then can be used to control B. cinerea disease pre- and postharvest. [ABSTRACT FROM AUTHOR]

Copyright of China Brewing is the property of China Brewing Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Green mould, caused by Trichoderma aggressivum, is one of the major fungal diseases of button mushrooms. The main problems in chemical disease control include a lack of effective agents, the occurrence of pathogen resistance to pesticides, and the harmful impact on the environment. In an attempt to find a solution, the interaction between two beneficial microorganisms, Bacillus amyloliquefaciens B-241 (an antifungal agent) and Streptomyces flavovirens A06 (a yield stimulant), was investigated in vivo. The synergy factor (SF) was calculated as a ratio between the observed and expected impact on the yield or efficacy of disease suppression after artificial inoculation with T. aggressivum. The highest control of T. aggressivum was achieved by joint application of the two beneficial microorganisms. The additive interaction between microorganisms in efficacy against the pathogen was revealed. The largest yield was obtained in mushroom beds sprayed with the two beneficial microorganisms combined (B-241 80% and A06 20%). Regarding the impact on the yield, synergistic interaction between the two microorganisms was confirmed (SFs were 1.62 or 1.52). The introduction of optimized microbial combinations could create new possibilities for biorational edible mushroom protection, with improved yield and quality and reduced risks to human health and the environment. [ABSTRACT FROM AUTHOR]

Background: Effective control of shot-hole disease in flowering cherries is challenging because of multiple causative pathogens (bacteria and fungi). Bacillus species are well-known for their ability to control plant pathogens; therefore, biological control potential of a Bacillus isolate, B. velezensis 8–2, against SH disease on flowering cherry trees was investigated. Results: This study revealed strong antimicrobial activity of Bacillus velezensis 8–2 against various plant pathogenic bacteria and fungi, particularly focusing on Xanthomonas arboricola pv. pruni (Xap) and Mycosphaerella cerasella (Mc), which cause shot-hole (SH) disease in flowering cherry trees. In vitro assays showed that the fermentation filtrate of B. velezensis 8–2 inhibited bacterial and fungal growth with minimum inhibitory concentrations of 1.25–10% and 2.5–10%, respectively. UPLC-Q–Orbitrap–MS analysis revealed that B. velezensis 8–2 produced antagonistic compounds, including polyketides (difficidin and oxydifficidin) and cyclic lipopeptides (iturin A, fengycin, and surfatin). To enhance antimicrobial activity, fermentation parameters for optimal production of two antibacterial and three antifungal compounds were investigated in a 5 L jar fermenter. By regulating the agitation speed to sustain the state of vegetative cells, the production period was extended by 20 h at 400 rpm, resulting in maximum yields of 86.6 μg/mL for difficidin and 150.0 μg/mL for oxydifficidin within a 72 h fermentation period. In a field trial, a 500-fold diluted 10% suspension concentrate formulation of B. velezensis 8–2 effectively inhibited the development of SH disease, demonstrating 66.6% disease control and a 90.2% disease symptoms reduction. Conclusions: This is the first report to assess the disease control efficacy of B. velezensis for the biocontrol of SH disease in the field. These results suggest that the application of B. velezensis 8–2 could serve as a practical alternative for managing various bacterial and fungal diseases, including the management of SH disease in flowering cherry trees. [ABSTRACT FROM AUTHOR]

This study aimed to optimize the production of keratinase by Bacillus tropicus KRKJVR 5 using response surface methodology (RSM). The factors considered were temperature (20 to 40°C), pH (5 to 9), inoculum size (0.5 to 2.5%), incubation period (24 to 120 hours) and agitation speed (RPM) (50 to 350). A total of 32 experimental runs were conducted based on the central composite design (CCD) model, with observed keratinase activity ranging from 2.00 to 13.33 U/mL. The highest keratinase activity (13.33 U/mL) was observed under the conditions of 30°C temperature, pH 7.0, 1.5% inoculum size, 72 hours incubation period and 150 RPM. The lowest activity (2.00 U/mL) was recorded at extreme conditions of low pH (3.0) and high temperature (50°C), highlighting the sensitivity of keratinase production to these factors. The regression analysis revealed a significant model with an R-squared value of 93.78%, indicating a strong fit to the data. The ANOVA results further supported the significance of these factors, with the overall model being highly significant (F-Value = 8.30, P-Value = 0.000). The contour plots demonstrated the optimal conditions for maximizing keratinase activity. The study effectively identified the optimal conditions for keratinase production by Bacillus tropicus KRKJVR 5 using response surface methodology. The results indicate that a temperature of 30°C, pH of 7.0, inoculum size of 1.5%, incubation period of 72 hours, and agitation speed of 150 RPM are ideal for producing high levels of keratinase. These findings provide valuable insights for scaling up the process for industrial applications, emphasizing the importance of precise control over culture conditions to achieve high enzyme yields. [ABSTRACT FROM AUTHOR]

为了筛选高产脂肪酶菌株并探究其对高含油废水的降解能力，采用传统的微生物筛选法从餐厨废水中分离筛选菌株，考察菌株对高含油废水（油脂含量20 g/L）的油脂降解率和产脂肪酶酶活，并对产脂肪酶酶活较高的菌株进行鉴定。采用单因素实验和响应面实验对鉴定菌株发酵产脂肪酶的工艺条件进行优化。结果表明：从餐厨废水中筛选出3株细菌、2株酵母菌，其中2株细菌可在高含油废水中快速生长代谢，油脂降解率和产脂肪酶酶活均较高，经鉴定1株为解淀粉芽孢杆菌（Bi），1株为鲁氏不动杆菌（Bu）；Bi产脂肪酶最优发酵工艺条件为pH 6.69、氯化钠含量301 g/L、蛋白胨含量6.01 g/L；Bu产脂肪酶最优发酵工艺条件为pH 5.07、氯化钠含量6.10 g/L、蛋白胨含量9.38 g/L；在最优发酵工艺条件下，Bi和Bu产脂肪酶酶活分别为（222.83±0.91）U/mL和（231.50±2.28）U/mL，优化后的Bu产脂肪酶酶活甚至高于初始脂肪酶酶活更高的Bi。综上，2株细菌具有高含油废水降解能力，具备广阔的应用前景。In order to screen high lipase-producing strains and explore the ability to degrade highly oily wastewater, the traditional microbial screening method was used to select the strains from the kitchen wastewater, and the oil degradation rate of highly oily wastewater (oil content 20 g/L) and the lipase activity of the selected strains were studied. Strains with higher lipase production activity were identified. Furthermore, single factor experiment and response surface methodology were employed to optimize the fermentation conditions for lipase production of the identified strains. The results indicated that three bacterial strains and two yeast strains were screened from kitchen wastewater, two bacteria grew and metabolized rapidly in highly oily wastewater, and the oil degradation rate and lipase activity were higher, which were identified as Bacillus amyloliquefaciens （Bi）and Acinetobacter lwoffii（Bu）, respectively. The optimal fermentation conditions for lipase production by Bi were pH 6.69, NaCl content 3.01 g/L, peptone content 6.01 g/L, and lipase activity was (222.83±0.91) U/mL, while that of Bu were pH 5.07, NaCl content 6.10 g/L, peptone content 9.38 g/L, and the lipase activity was (231.50±2.28) U/mL. The lipase activity of Bu after optimization even higher than that of Bi , which had a greater initial lipase activity. In conclusion, these two bacterial strains show a high biodegradation performance for highly oily wastewater, and they have a wide application prospect.

Abstract Background In this study, we isolated a cellulase-producing bacterium, Bacillus amyloliquefaciens strain elh, from rice peel. We employed two optimization methods to enhance the yield of cellulase. Firstly, we utilized a one-variable-at-a-time (OVAT) approach to evaluate the impact of individual physical and chemical parameters. Subsequently, we employed response surface methodology (RSM) to investigate the interactions among these factors. We heterologously expressed the cellulase encoding gene using a cloning vectorin E. coli DH5α. Moreover, we conducted in silico molecular docking analysis to analyze the interaction between cellulase and carboxymethyl cellulose as a substrate. Results The bacterial isolate eh1 exhibited an initial cellulase activity of 0.141 ± 0.077 U/ml when cultured in a specific medium, namely Basic Liquid Media (BLM), with rice peel as a substrate. This strain was identified as Bacillus amyloliquefaciens strain elh1 through 16S rRNA sequencing, assigned the accession number OR920278 in GenBank. The optimal incubation time was found to be 72 h of fermentation. Urea was identified as the most suitable nitrogen source, and dextrose as the optimal sugar, resulting in a production increase to 5.04 ± 0.120 U/ml. The peak activity of cellulase reached 14.04 ± 0.42 U/ml utilizing statistical optimization using Response Surface Methodology (RSM). This process comprised an initial screening utilizing the Plackett–Burman design and further refinement employing the BOX -Behnken Design. The gene responsible for cellulase production, egl, was effectively cloned and expressed in E. coli DH5α. The transformed cells exhibited a cellulase activity of 22.3 ± 0.24 U/ml. The egl gene sequence was deposited in GenBank with the accession number PP194445. In silico molecular docking revealed that the two hydroxyl groups of carboxymethyl cellulose bind to the residues of Glu169 inside the binding pocket of the CMCase. This interaction forms two hydrogen bonds, with an affinity score of −5.71. Conclusions Optimization of cultural conditions significantly enhances the yield of cellulase enzyme when compared to unoptimized culturing conditions. Additionally, heterologous expression of egl gene showed that the recombinant form of the cellulase is active and that a valid expression system can contribute to a better yield of the enzyme.

Transcriptional factors-based biosensors are commonly used in metabolic engineering for inducible control of gene expression and related applications such as high-throughput screening and dynamic pathway regulations. Mining for novel transcriptional factors is essential for expanding the usability of these toolsets. Here, we report the identification, characterization, and engineering of a phenolic acid responsive regulator PadR from Bacillus amyloliquefaciens (BaPadR). This BaPadR-based biosensor system showed a unique ligand preference and exhibited a high output strength comparable to that of commonly used inducible expression systems. Through engineering the DNA binding region of BaPadR, we further enhanced the dynamic range of the biosensor system. The DNA sequences that are responsible for BaPadR recognition were located by promoter truncation and hybrid promoter building. To further explore the tunability of the sensor system, base substitutions were performed on the BaPadR binding region of the phenolic acid decarboxylase promoter (PpadC) and the hybrid promoter. This novel biosensor system can serve as a valuable tool in future synthetic biology applications.

Background: Natural products are important sources for the discovery of new biopesticides to control the worldwide destructive pests Acyrthosiphon pisum Harris. Here, insecticidal substances were discovered and characterized from the secondary metabolites of the bio-control microorganism Bacillus velezensis strain ZLP-101, as informed by whole-genome sequencing and analysis. Results: The genome was annotated, revealing the presence of four potentially novel gene clusters and eight known secondary metabolite synthetic gene clusters. Crude extracts, prepared through ammonium sulfate precipitation, were used to evaluate the effects of strain ZLP-101 on Acyrthosiphon pisum Harris aphid pests via exposure experiments. The half lethal concentration (LC50) of the crude extract from strain ZLP-101 against aphids was 411.535 mg/L. Preliminary exploration of the insecticidal mechanism revealed that the crude extract affected aphids to a greater extent through gastric poisoning than through contact. Further, the extracts affected enzymatic activities, causing holes to form in internal organs along with deformation, such that normal physiological activities could not be maintained, eventually leading to death. Isolation and purification of extracellular secondary metabolites were conducted in combination with mass spectrometry analysis to further identify the insecticidal components of the crude extracts. A total of 15 insecticidal active compounds were identified including iturins, fengycins, surfactins, and spergualins. Further insecticidal experimentation revealed that surfactin, iturin, and fengycin all exhibited certain aphidicidal activities, and the three exerted synergistic lethal effects. Conclusions: This study improved the available genomic resources for B. velezensis and serves as a foundation for comprehensive studies of the insecticidal mechanism by Bacillus velezensis ZLP-101 in addition to the active components within biological control strains. [ABSTRACT FROM AUTHOR]

Background: Citrus canker caused by the bacterium Xanthomonas citri (Hasse 1915) is known as a dangerous disease that has serious economic impacts on citrus production in many tropical and subtropical countries. In Iran, Citrus canker disease has caused significant damage to various citrus fruits, particularly limes. Nowadays, employing antagonistic bacteria as an effective and environmentally friendly method for plant disease management has gained special importance. Results: Citrus leaf samples were collected from different regions of Iran, and after isolating epiphytic bacteria, ex planta and in planta investigations concerning antagonistic activities of the isolates against Xanthomonas citri pathotypes A and A* were performed. A total of 94 epiphytic bacterial isolates were isolated from citrus aerial parts. Based on biochemical, physiological, morphological, and genotypic tests, it was determined that these bacteria belong to the Bacillus and Staphylococcus genera. The highest inhibition activity against the pathogenic bacterium was related to isolates D4 and D5. Using the molecular method and the resulting dendrogram, it was found that these isolates were most similar to Bacillus amyloliquefaciens. The present findings demonstrated that pathogenicity test on key lime leaves infected with X. citri pathotypes A and A*, along with the application of the biocontrol strain B. amyloliquefaciens, resulted in a significant reduction in the number of canker lesions. Conclusion: The results strongly suggested that the identified antagonistic bacterial isolates hold promising potential as biocontrol agents for managing citrus bacterial canker disease. [ABSTRACT FROM AUTHOR]

Aromatic compounds are known anti-amyloid aggregates. Their effect on amorphous aggregates of proteins is, however, less studied. We chose aromatic amino acids Trp, Tyr, and Phe, as well as another known stabilizer (i.e. Arg), as potential compatible solvents to be tested on Bacillus amyloliquefaciens alpha-amylase (BAA). Among these additives, Phe was the only one to be effective on the thermal inactivation and amorphous aggregation of BAA, while preserving its intrinsic activity. A concentration of 50 mM Phe was used to test its potential in counteracting the deleterious effect of BAA amorphous aggregates in vivo. After 21 days of daily subcutaneous injections of the native enzyme to mice, amorphous aggregates of BAA, as well as aggregates produced in presence of 50 mM Phe, the tissues located at the site of injection were studied histologically. Amorphous aggregates caused an increase in macrophages and lipid droplets. Serum levels of IL6 and TNF-α were also accordingly elevated and indicative of an inflammation state. Aggregates also resulted into increased levels of glucose, triglycerides and cholesterol, as well as liver enzymes SGOT and SGPT. On the other hand, the presence of Phe prevented this exacerbated inflammatory state and the subsequent impairment of biochemical parameters. In conclusion, Phe is an interesting compound for both stabilizing proteins and counteracting the pathological effect of amorphous aggregates. [ABSTRACT FROM AUTHOR]

Introduction: Optimal exploitation of the huge amounts of agro-industrial residuals that are produced annually, which endangers the ecosystem and ultimately contributes to climate change, is one of the solutions available to produce value-added compounds. Aim and objectives: This study aimed at the economic production and optimization of surfactin. Therefore, the production was carried out by the microbial conversion of Potato Peel Waste (PPW) and Frying Oil Waste (FOW) utilizing locally isolated Bacillus halotolerans. Also, investigating its potential application as an antimicrobial agent towards some pathogenic strains. Results: Screening the bacterial isolates for surfactin production revealed that the strain with the highest yield (49 g/100 g substrate) and efficient oil displacement activity was genetically identified as B. halotolerans. The production process was then optimized utilizing Central Composite Design (CCD) resulting in the amelioration of yield by 11.4% (from 49 to 55.3 g/100 g substrate) and surface tension (ST) by 8.3% (from 36 to 33 mN/m) with a constant level of the critical micelle concentration (CMC) at 125 mg/L. Moreover, the physiochemical characterization studies of the produced surfactin by FTIR, 1H NMR, and LC–MS/MS proved the existence of a cyclic lipopeptide (surfactin). The investigations further showed a strong emulsification affinity for soybean and motor oil (E24 = 50%), as well as the ability to maintain the emulsion stable over a wide pH (4–10) and temperature (10–100 °C) range. Interestingly, surfactin had a broad-spectrum range of inhibition activity against Bacillus subtilis, Staphylococcus aureus, Pseudomonas aeruginosa, klebsiella pneumonia, and Candida albicans. Conclusion: Subsequently, the screening of the isolates and the utilized food-processing wastes along with the extraction technique resulted in a high yield of surfactin characterized by acceptable ST and CMC levels. However, optimization of the cultural conditions to improve the activity and productivity was achieved using Factor-At-A-Time (OFAT) and Central Composite Design (CCD). In contrast, surface activity recorded a maximum level of (33 mN/n) and productivity of 55.3 g/100 g substrate. The optimized surfactin had also the ability to maintain the stability of emulsions over a wide range of pH and temperature. Otherwise, the obtained results proved the promising efficiency of the surfactin against bacterial and fungal pathogens. [ABSTRACT FROM AUTHOR]

Strawberry root rot caused by Fusarium solani is one of the main diseases of strawberries and significantly impacts the yield and quality of strawberry fruit. Biological control is becoming an alternative method for the control of plant diseases to replace or decrease the application of traditional chemical fungicides. To obtain antagonistic bacteria with a high biocontrol effect on strawberry root rot, over 72 rhizosphere bacteria were isolated from the strawberry rhizosphere soil and screened for their antifungal activity against F. solani by dual culture assay. Among them, strains CMS5 and CMR12 showed the strongest inhibitory activity against F. solani (inhibition rate 57.78% and 65.93%, respectively) and exhibited broad-spectrum antifungal activity. According to the phylogenetic tree based on 16S rDNA and gyrB genes, CMS5 and CMR12 were identified as Bacillus amyloliquefaciens. Lipopeptide genes involved in surfactin, iturin, and fengycin biosynthesis were detected in the DNA genomes of CMS5 and CMR12 by PCR amplification. The genes related to the three major lipopeptide metabolites existed in the DNA genome of strains CMS5 and CMR12, and the lipopeptides could inhibit the mycelial growth of F. solani and resulted in distorted hyphae. The inhibitory rates of lipopeptides of CMS5 and CMR12 on the spore germination of F. solani were 61.00% and 42.67%, respectively. The plant-growth-promoting (PGP) traits in vitro screening showed that CMS5 and CMR12 have the ability to fix nitrogen and secreted indoleacetic acid (IAA). In the potting test, the control efficiency of CMS5, CMR12 and CMS5+CMR12 against strawberry root rot were 65.3%, 67.94% and 88.00%, respectively. Furthermore, CMS5 and CMR12 enhanced the resistance of strawberry to F. solani by increasing the activities of defense enzymes MDA, CAT and SOD. Moreover, CMS5 and CMR12 significantly promoted the growth of strawberry seedlings such as root length, seedling length and seedling fresh weight. This study revealed that B. amyloliquefaciens CMS5 and CMR12 have high potential to be used as biocontrol agents to control strawberry root rot. [ABSTRACT FROM AUTHOR]

Electronic waste (e-waste) illegally disposal in Thailand is becoming more widespread. A sustainable metal recovery technology is needed. A phytotechnology called "phytomining" of metals such as nickel (Ni) is a promising technology providing a sustainable solution to the growing e-waste problems. This study investigated the ability of Acacia species in association with e-waste site isolated, plant growth-promoting rhizobacteria (PGPR), Bacillus amyloliquefaciens. Acacia mangium accumulated higher Ni in their tissues when Ni concentrations in soil were lower than 200 mg kg−1. The inoculation of PGPR B. amyloliquefaciens enhanced Ni uptake and accumulation in the leaves, stem, and root. The results showed that the highest Ni concentration was found in the root ash (825.50 mg kg−1) when inoculated plants were grown in soil containing 600 mg kg−1 Ni. Hence, the Ni recovery process and mass balance were performed on root ashes. The highest Ni recovery was 91.3% from the acid (H2SO4) leachate of the ash of inoculated plant treated with 600 mg kg−1 Ni. This demonstrates the feasibility of PGPR-assisted phytomining from Ni-contaminated soil. Phytomining of Ni from any e-waste contaminated sites using Acacia mangium in combination with B. amyloliquefaciens can promote plant growth and improve the uptake of Ni. Phytomining from electronic waste is an appealing technology that can provide a long-term waste management strategy while valuable trace metals can be recovered. In this study, we evaluated the nickel phytomining ability of Acacia mangium in association with PGPR Bacillus amyloliquefaciens. The results from this study showed that Ni recovery from phytomass using A. mangium with B. amyloliquefaciens can be further improved leading to a sustainable waste management strategy. [ABSTRACT FROM AUTHOR]

Simple Summary: Necrotic enteritis caused by Clostridium perfringens (CP) is an important disease for the poultry industry. It leads to decreased growth and production performance in chickens. Bacillus amyloliquefaciens SC06 (BaSC06) is known to play a role in preventing damage from the bacterial infection. However, whether CP could affect brain function and behavior and whether BaSC06 has a preventive role in infected animals are not yet reported. Thus, the aim of this study was to investigate whether BaSC06 has a preventative effect on broiler chickens infected by CP. Our results showed that CP is associated with a reduction in stress and fear-related behaviors and causes pathological damage to the pia and cortex of the brain, as well as inhibiting the expression of genes related to stress, while the treatment of BaSC06 alleviates these adverse effects. Poultry studies conducted on Clostridium perfringens (CP) mainly focus on the effects of intestinal health and productive performance. Notably, the probiotic Bacillus amyloliquefaciens SC06 (BaSC06) is known to play a role in preventing bacterial infection. However, whether CP could induce the changes in brain function and behaviors and whether BaSC06 could play roles in these parameters is yet to be reported. The aim of this study was to evaluate the effects of BaSC06 on stress-related behaviors and gene expression, as well as the brain morphology and mRNA sequence of the hypothalamus in broiler chickens. A total of 288 one-day-old chicks were randomly divided into four groups: (1) a control group with no treatment administered or infection; (2) birds treated with the BaSC06 group; (3) a CP group; and (4) a BaSC06 plus CP (Ba_CP) group. The results showed that stress and fear-related behaviors were significantly induced by a CP infection and decreased due to the treatment of BaSC06. CP infection caused pathological damage to the pia and cortex of the brain, while BaSC06 showed a protective effect. CP significantly inhibited hypothalamic GABA and promoted HTR1A gene expression, while BaSC06 promoted GABA and decreased HTR1A gene expression. The different genes were nearly found between the comparisons of control vs. Ba group and Ba vs. CP group, while there were a great number of different genes between the comparisons of control vs. Ba_CP as well as CP vs. Ba_CP. Several different gene expression pathways were found that were related to disease, energy metabolism, and nervous system development. Our results will help to promote poultry welfare and health, as well as provide insights into probiotics to replace antibiotics and reduce resistance in the chicken industry. [ABSTRACT FROM AUTHOR]

Microbial infection can pose a great threat to health of farmed fish. This study aimed to investigate the probiotic characteristics of Bacillus cereus strain fkW8-1-2 isolated from intestine of WCC and its anti-biofilm activity against pathogenic bacteria. The strain fkW8-1-2 showed a high resistance to low pH, bile salt and lysozyme during long-term incubation. The strain fkW8-1-2 displayed a gradual increase of cell surface hydrophobicity with various forms of hydrocarbons. The strain fkW8-1-2 showed the remarkable autoaggregation and coaggregation activity with A. hydrophila L3-3 and E. tarda 1l-4. The culture medium (CM) and cell-free supernatants (CFS) of strain fkW8-1-2 at 48 h cultivation could attenuate biofilm formation of A. hydrophila and E. tarda with the maximum inhibition rates. In addition, the intact cells of strain fkW8-1-2 exhibited the strong antioxidant activity for DPPH removal and superoxide anion clearance. These results indicated that strain fkW8-1-2 possessing probiotic characteristics can pose a protective role in health of farmed fish. [ABSTRACT FROM AUTHOR]