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Introduction: The production of high-quality food for the growing world population on the one hand and the reduction of chemical-synthetic pesticides on the other hand represents a major challenge for agriculture worldwide. The effectiveness of a combination of microbial and non-microbial biostimulants (BSs) with various nitrogen (N) forms in pathogen defense is discussed as a promising, but still poorly understood bio-based alternative for crop protection. Methods: For this reason, nitrate and stabilized ammonium fertilizer both combined with a consortium of Pseudomonas brassicacearum , Bacillus amyloliquefaciens , and Trichoderma harzianum as soil treatment or with a mixture of seaweed extract (Ascophyllum nodosum) together with chitosan-amended micronutrient fertilizer as foliar spray application were compared under controlled greenhouse conditions. Furthermore, a combination of microbial and different non-microbial BSs (seaweed extracts + chitosan) and micronutrients with nitrate or with stabilized ammonium fertilizer was tested under field conditions to improve nutrient availability, promote plant growth, and suppress Zymoseptoria tritici (Zt) in winter wheat. Results and discussion: While plant-protective effects against Zt by the microbial consortium application could be observed particularly under ammonium fertilization, the application of seaweed extract–chitosan mixture expressed plant defense against Zt more strongly under nitrate fertilization. In the field trial, the combination of microbial consortium with the seaweed extract–chitosan mixture together with micronutrients zinc (Zn) and manganese (Mn) showed positive effects against Zt under ammonium fertilization, associated with increased levels of defense metabolites. Furthermore, the additional input of Zn and copper (Cu) from the chitosan application improved the micronutrient status by minimizing the risk of Zn and Cu deficiency under controlled and field conditions. The use of BSs and the inoculation of Zt did not show any effects on plant growth and yield neither under controlled greenhouse conditions nor in the field. Summarized, microbial and non-microbial BSs separately applied or even combined together as one treatment did not influence plant growth or yield but made a positive contribution to an N form-dependent promotion of pathogen defense. [ABSTRACT FROM AUTHOR]

• Potential plant growth-promoting rhizobacteria screened from tomato rhizosphere soil. • Biochemical and molecular characterization of selected four isolates were done and taxonomy identified. • Plant growth promoting traits of the candidate strains were evaluated both at laboratory and greenhouse level. • Greenhouse trail and symbiotic effectiveness of the strains conducted using tomato as host plant. • To improve tomato-strain interaction different possible phosphorus sources were added. Numerous phosphate solubilizing bacteria (PSB) are found in the rhizosphere, benefiting the host plant in different mechanisms and promoting sustainable agriculture. They improve soil fertility with minimum cost requirements using an eco-friendly approach, which is an essential attribute for small-scale farm production. Thus, isolation, characterization, and evaluation of symbiotic effectiveness are hierarchical procedures to develop bioinoculants. Using a dual (plate and liquid medium) screening technique and a greenhouse trial, four potential PSB strains (Mk-1–25, Mk-13–16, Mk-20–7, and Mk-20–20) were selected from tomato rhizosphere soil. All isolates exhibited the following traits: produced colony clear-zone, lowered liquid medium pH, gram-positive, produced urease and IAA, dissolved substantial P from various substrates, symbiotically effective, and improved tomato growth and yield. Taxonomically, they belong to Bacillus and Priestia species (i.e., Mk-1–25 Bacillus halotolerance, Mk-13–16 Bacillus amyloliquefaciens, Mk-20–7 Bacillus megaterium, and Mk-20–20 Priestia megaterium). Among the current strains, Bacillus halotolerance recorded higher SI (3.11), was able to grow in extreme conditions (10% salt, up to 45 °C), produced HCN and siderophore, and improved tomatoes' shoot length and weight, in contrast, Mk-20–20 produced HCN, siderophore, was able to fix nitrogen, improved tomato germination, shoot dry weight, and fruit weight. Various P-supplements (Ca 3 (PO 4) 2 , bonemeal, FePO 4 , AlPO 4 , compost, and DAP fertilizer) were added to induce tomato-strain symbiotic interaction; hence, compost substantially promoted the interaction and resulted in higher symbiotic effectiveness. Ca 3 (PO 4) 2 was a good media composite preferred by most PSB strains; consequently, a higher concentration (219 µg/ml) of dissolved P was recorded from the liquid medium after 10 days of incubation than other substrates. Based on the data obtained from laboratory and greenhouse trials, the current strains were found to be potential candidate. Future work should confirm their efficacy at the field level using model host crops at different sites to recommend them as farm inputs and biofertilizer. [ABSTRACT FROM AUTHOR]

Biofertilizers constitute a safe way to alleviate the impacts of water shortage and the overload of chemical fertilizers. This work focuses on the effects of Arbuscular Mycorrhizal Fungi (AMF) and Plant Growth-Promoting Rhizobacteria (PGPR) on potato's agro-physiological response, beneath the reduction of water, nitrogen (N), phosphorous (P) and potassium (K) fertilizers. Five microbioal treatments (C: Control, AMF: Mycorhizae, B1: Bacillus halotolerans , B2: Bacillus amyloliquefaciens and B1B2: B. halotolerans + B. amyloliquefaciens) were tested in arrangement with two nitrogen-phosphorous-potassium (NPK) rates (F1: Entire rate, F ½: Half rate) and three irrigation levels (100 % of crop water requirement: 100 % ETc; 75 % ETc; 50 % ETc) in a two year factorial split plot design. We studied vegetative growth, photosynthetic activity, chlorophyll fluorescence, water status, osmoticums, N, P, K and enzymatic antioxidants accumulation. Data obtained in 2019–2022 showed that AMF and B1B2 biofertilizers were beneficial to improve Root/Shoot, Dry Underground Part/Aerial Part, leaf area (LA), water saturation deficit (WSD), chlorophyll index (SPAD) and tuber yield under 75 % ETc. The photosynthetic promoter effect of biofertilizers under 75 % ETc, compared to 50 % ETc was observed in the following trend B1B2>AMF>B1. The efficacy of B1B2 and AMF were coupled to high catalase (CAT) activity. Potatoes treated with B1B2 were found to be efficient for 75 % ETc in terms of proline accumulation. The AMF was more effective in terms of soluble sugars (SS) accumulation and control of osmotic potential (Ψs). Taking together, the B1B2 and AMF could be regarded as efficient biofertilizers under 75 % ETc, alleviating the impacts of water stress and the problem of excessive fertilization in potatoes. 100 % ETc: 100 % crop water requirement; 75 % ETc: 75 % crop water requirement; 50 % ETc: 50 % crop water requirement; F1: 100 % NPK; F1/2: 50 % NPK; AMF: arbuscular mycorhizal fungi; B1: B. halotolerans ; B2: B. amyloliquefaciens ; B1B2: B. halotolerans + B. amyloliquefaciens (B1B2). [Display omitted] • Pooled PGPR bacteria and mycorhizae are efficient biofertilizers for 75 % ETc potatoes. • Efficacy of pooled PGPR and mycorhizae is linked to enhanced catalase activity. • Pooled PGPR enhanced proline accumulation. • Mycorhizae increased sugars accumulation and controlled the osmotic potential. [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]

The aim of our investigation is to elucidate the impact of ultrasonic treated Bacillus amyloliquefaciens (B. amyloliquefaciens) on production of peptides during solid-state fermentation of soybean meal and its mechanisms. There was a substantial enhancement in levels of peptides, biomass, and protease activity within fermented soybean meal by 14.61%, 65.96%, and 16.58%, respectively, relative to control group (p < 0.05). Nevertheless, omics analysis and qRT-PCR verification declared that ultrasonic treatment did not bring the growing of B. amyloliquefaciens or the protease production in single cell, but accelerate the germination of spores. Genes encoding spo0A, spo0B, spo0F, spo0J were all substantially down-regulated ranged from − 0.25 to − 1.75 (p < 0.05). Concurrently, the gene encoding sleB displayed a remarkable up-regulation with log2-fold change of + 3.07 (p < 0.05). Besides, their respective proteins performed the same change tendency. Moreover, after ultrasonic treatment, spores germination rate and DPA content significantly increased by 3.29 and 12.14 times, respectively. Meanwhile, OD600 of spores suspension obviously decreased by 37.81% (p < 0.05). Most importantly, Pearson's correlation analysis revealed that peptides yield in fermented products was strongly correlated with spores germination (Pearson's correlation coefficient r = 0.839, p < 0.01). In brief, ultrasonic treatment promoted the germination of spores in the inoculum, which resulted in microbial proliferation and protease activity raising in fermented products, and consequently improving peptides yield. The improvement of spore germination rate after ultrasonic treatment might be achieved by reducing bacterial aggregation and lowering viscosity. [ABSTRACT FROM AUTHOR]

The focal point of probiotic efficacy and a crucial factor influencing poultry cultivation lies in the level of intestinal inflammation. In conventional farming processes, the reduction of intestinal inflammation generally proves advantageous for poultry growth. This study investigated the impact of Bacillus amyloliquefaciens TL (B.A.-TL) on inflammatory factor expression at both tissue and cellular levels, alongside an exploration of main active secondary metabolites. The results demonstrated that broiler feeding with a basal diet containing 4 × 109 CFU/kg B.A.-TL markedly enhanced chicken growth performance, concomitant with a significant decrease in the expression of genes encoding inflammatory cytokines (e.g., CCL4, CCR5, XCL1, IL-1β, IL-6, IL-8, LITAF, and LYZ) in jejunum and ileum tissues. The extracellular polysaccharides of B.A.-TL (EPS-TL) exhibited notable suppression of elevated inflammatory cytokine expression induced by Escherichia coli O55 lipopolysaccharides (LPS) in chicken macrophage-like cells (HD11) and primary chicken embryonic small intestinal epithelial cells (PCIECs). Moreover, EPS-TL demonstrated inhibitory effect on NF-κB signaling pathway activation. These findings suggested that the metabolic product of B.A.-TL (i.e., EPS-TL) could partly mitigate the enhanced expression of inflammatory factors induced by LPS stimulation, indicating its potential as a key component contributing to the anti-inflammatory effects of B.A.-TL. [ABSTRACT FROM AUTHOR]

Background: Schistosomiasis japonica is a serious threat to human health. It causes damage to the intestine and liver. Probiotic therapy has been shown to be effective in alleviating intestinal diseases and improving host health. Previous studies have found that Bacillus amyloliquefaciens could alleviate the pathological symptoms of schistosomiasis japonica, but the regulatory mechanism of alleviating schistosomiasis japonica is still unknown. Principal findings: This study analyzed the dynamic changes of intestinal microbiome in mice infected with Schistosoma japonicum after the intervention of B. amyloliquefaciens and its connection to host metabolism by multi-omics sequencing technology. B. amyloliquefaciens was found to significantly regulate the homeostasis of intestinal microbiota by promoting the growth of beneficial bacteria and inhibiting potential pathogenic bacteria and protect the number of core microbes. Meanwhile, the genes related to the metabolism of glycerophospholipids and amino acid from intestinal microbiome changed significantly, and were shown to be significantly positively correlated with the associated metabolites of microbial origin. Moreover, host metabolism (lipid metabolism and steroid hormone biosynthesis) was also found to be significantly regulated. Conclusions: The recovery of intestinal microbial homeostasis and the regulation of host metabolism revealed the potential probiotic properties of B. amyloliquefaciens, which also provided new ideas for the prevention and adjuvant treatment of schistosomiasis japonica. Author summary: Schistosomiasis, which seriously threatens human health, is the world's second largest tropical disease caused by schistosome infection. Praziquantel has many problems such as side effects and drug resistance, so it is urgent to develop new prevention strategies. Bacillus amyloliquefaciens has been reported to alleviate the pathological damage of intestinal diseases, which can be used as a potential strategy to alleviate granuloma and fibrosis induced by schistosomiasis japonica in intestine and liver. However, the mechanism of B. amyloliquefaciens regulating schistosomiasis japonica through the mediation of intestinal microbiome is still unclear. In this study, we conducted joint analysis of the gut microbiome and host serum metabolites through mouse models and multi-omics sequencing technology, and found that the intragastric administration of B. amyloliquefaciens could regulate the restoration of intestinal microbiome and the secretion of metabolites derived from intestinal microbiome in mice, improve lipid metabolism disorder and hormone secretion in mice, and ultimately reduce the pathological response of mice infected with Schistosoma japonicum. This study highlights the crosstalk between intestinal microbiome and the host, providing an important reference for the precise treatment based on targeted microbiota, and also providing a new strategy for the prevention and adjuvant treatment of schistosomiasis japonica. [ABSTRACT FROM AUTHOR]

Background: Milk clotting enzymes, essential for milk coagulation in cheese production, are obtained from the stomach of young ruminants, an expensive and limited source. This study was accomplished by finding a suitable alternative. Bacterial isolates recovered from honey were screened for milk clotting enzyme activity. and further, by immobilization of the microorganisms to enhance stability and facilitate their repeated use. Result: The most effective enzyme was produced by a microbe identified as Bacillus amyloliquefaciens based on 16 S rRNA sequencing. The cells were encapsulated in Ca2+ alginate beads. These beads retained complete enzyme production after being used five times. Glucose and Soybean were selected as the most favorable carbon and nitrogen sources, respectively. The optimum temperature for activity was 35 ℃ for both free and immobilized cells but as the temperature was increased to 55 °C and above, the encapsulated form retained more activity than the free cells. The pH optimum shifted from 6.5 to 7 for the free cells to 7–7.5 for the immobilized cells. The immobilization process decreased the activation energy for enzyme production and activity, prolonged the enzyme half-life, and increased the deactivation energy. Enzyme produced by immobilized cells generated a more compact cheese. Conclusions: The finding of this study was to identify a less expensive source of milk-clotting enzymes and confirm the success of cell immobilization in improving cell rigidity and stability. Also, immobilization of this B. amyloliquefaciens strain offers an enzyme source of value for industrial production of cheese. [ABSTRACT FROM AUTHOR]

Bacillus species are among the most studied and commercially exploited biocontrol agents of plant‐parasitic nematodes. These antagonists may control nematodes by producing toxic or repellent substances, inducing systemic resistance in plants and disrupting nematode chemotaxis. Understanding the mechanism of action of antagonists increases the likelihood of success for microbiological nematicides under field conditions. Therefore, the objective of this work was to elucidate the mechanisms of action of Bacillus amyloliquefaciens strain BaNCT02 against Meloidogyne incognita. We assessed the potential of this strain for forming biofilm in roots and producing volatile and non‐volatile toxic substances. BaNCT02 did not induce systemic resistance in tomato plants against M. incognita. Scanning electron microscopy and chemotaxis analyses revealed that the bacteria form a biofilm on soybean roots and 67% of second‐stage juveniles of M. incognita are repelled by common bean roots treated with the antagonist. Additionally, BaNCT02 produces substances with toxic effects against eggs and juveniles of M. incognita, including volatile organic compounds such as 2‐undecanone and 2‐heptanone, as well as non‐volatile metabolites like proteases and chitinases. The suppressive effect of these substances on hatching and mortality of juveniles varied from approximately 70% to more than 90%. We concluded that B. amyloliquefaciens BaNCT02 forms a biofilm on root surfaces and produces volatile and non‐volatile metabolites with nematicidal and repellent effects against M. incognita. [ABSTRACT FROM AUTHOR]

The unique eco-environment of the Qinghai–Tibet Plateau breeds abundant microbial resources. In this research, Bacillus amyloliquefaciens GL18, isolated from the rhizosphere of Kobresia myosuroides from an alpine meadow, and the antagonistic activity, bacteriostatic hydrolase activity, and low temperature, salt, and drought resistance of it were determined and analysed. The seedlings of Avena sativa were root-irrigated using bacteria suspensions (cell concentration 1 × 107 cfu/mL) of GL18, and the growth-promoting effect of GL18 on it was determined under cold, salt and drought stress, respectively. The whole genome of GL18 was sequenced, and its functional genes were analysed. GL18 presented significant antagonistic activity to Fusarium graminearum, Fusarium acuminatum, Fusarium oxysporum and Aspergillus niger (inhibition zone diameter > 17 mm). Transparent zones formed on four hydrolase detection media, indicating that GL18 secreted cellulase, protease, pectinase and β-1,3-glucanase. GL18 tolerated conditions of 10 °C, 11% NaCl and 15% PEG-6000, presenting cold, salt and drought resistance. GL18 improved the cold, salt and drought tolerance of A. sativa and it showed significant growth effects under different stress. The total length of the GL18 genome was 3,915,550 bp, and the number of coding DNA sequence was 3726. Compared with the clusters of orthologous groups of proteins, gene ontology and kyoto encyclopedia of genes and genomes databases, 3088, 2869 and 2357 functional genes were annotated, respectively. GL18 contained gene clusters related to antibacterial substances, functional genes related to the synthesis of plant growth-promoting substances, and encoding genes related to stress resistance. This study identified an excellent Bacillus strain and provided a theoretical basis for improving stress resistance and promoting the growth of herbages under abiotic stress. [ABSTRACT FROM AUTHOR]

The escalating threat of chilli anthracnose and the adverse effects of chemical pesticides underscore the urgency for sustainable management of chilli anthracnose. This study aims to identify the potential endophytic bacteria as eco-friendly solutions to combat chilli anthracnose pathogen. Through evaluating their antagonistic effects, we aim to provide effective biological control strategies for this destructive plant disease. Among the 74 bacterial endophytes isolated from healthy chilli plants, Bacillus amyloliquefaciens (ENLB 4) exhibited the most pronounced antagonistic effect against the chilli anthracnose pathogen Colletotrichum acutatum. In vitro tests revealed that ENLB 4 inhibited the pathogen's growth by 56.43%. Additionally, the cell-free culture filtrate of ENLB 4 exhibited substantial inhibitory effects on pathogen growth at various concentrations (46.74% at 5%, 54.99% at 10%, and 63.55% at 15%, respectively). Similarly, volatile organic compounds produced by ENLB 4 resulted in a higher (37.78%) growth inhibition of the pathogen. Analysis of the culture filtrate using GC-MS identified 17 compounds, some of which possess antimicrobial properties (hexanoic acid, 3-Isobutylhexahydropyrrolo[1,2-a] pyrazine-1,4-dione, isovaleric acid), while others are known to induce systemic resistance in treated plants (acetic acid). These findings underscore the potential of endophytic bacteria, exemplified by B. amyloliquefaciens, as effective and environmentally friendly agents for disease management in agriculture. [ABSTRACT FROM AUTHOR]

There are many challenges in cotton cultivation, which are mainly linked to management practices and market demands. The textile commerce requirements are increasing but the effects of climate change on cotton cultivation are becoming an issue, as its commercial development depends significantly on the availability of favorable climatic parameters and the absence of insect pests. In this research, it was studied whether the use of two commercial strains as cotton seed coatings could effectively contribute to the previous obstacles. The experiment was carried out in semi-field conditions at the University of Ioannina. It used a completely randomized design and lasted for 150 days. The following treatments were tested: (a) coated seeds with a commercial strain of Beauveria bassiana (Velifer®); (b) coated seeds with a combination of Velifer® and a commercial strain of Beauveria bassiana (Selifer®); and (c) uncoated cotton seeds (control). The biostimulant effect of the two seed coatings was assessed against the growth characteristics of cotton, and the total chlorophyll and proline content. The bioinsecticidal effect was evaluated by measuring the population of Aphis gossypii on the cotton leaves. The proline effect increased by 15% in the treated plants, whereas the total chlorophyll was higher in the use of both Velifer® and Velifer®–Selifer® treatments by 32% and 19%, respectively. Aphid populations also decreased in the treated plants compared to the control plants (29.9% in Velifer® and 22.4% in Velifer®–Selifer®). Based on an assessment of the above parameters, it follows that the two seed coatings can significantly enhance the growth performance of cotton and reduce the abundance of A. gossypii. [ABSTRACT FROM AUTHOR]

The western corn rootworm, Diabrotica virgifera virgifera, (Coleoptera: Chrysomelidae) is a serious pest of maize in the USA and Europe. Microbial plant biostimulants such as bacteria, fungi, and algae are designed to stimulate plant nutrition and growth, with some hypothesized to also possess insecticidal properties. We tested 10 biostimulants (four bacteria, five fungi, and one alga) under laboratory and greenhouse conditions. Most biostimulants did not affect the eggs, larvae, or adults of D.v. virgifera. However, in the laboratory, 10% of biostimulants improved egg hatching, and 40% killed some larvae, including the fungi Beauveria bassiana, Rhizophagus irregularis, and Trichoderma asperellum, and the bacterium Ensifer meliloti. Under potted-plant conditions in the greenhouse, these insecticidal effects were not detectable. However, several biostimulants slightly increased height and shoot length of uninfested maize plants, but reduced volume and length of their roots as well as above-ground biomass. Interestingly, 30% of the biostimulants enhanced the plant's defence against larvae, for example, Bacillus amyloliquefaciens, B. subtilis, and E. meliloti. These may warrant further research into their modes of action as well as field trials to better understand and optimize their potential use in sustainable and integrated pest management. [ABSTRACT FROM AUTHOR]

The major challenge in employing high pressure (HP) at moderate temperature for sterilization is the remarkable resistance of bacterial spores. High isostatic pressure can initiate spore germination, enabling subsequent inactivation under mild conditions. However, not all spores could be triggered to germinate under pressure at temperatures =80°C so far. In this study, germination treatment combinations were evaluated for Bacillus spores involving moderate HP (150 MPa, 37°C, 5 min), very HP (vHP, 550 MPa, 60°C, 2.5 or 9 min), simple and complex nutrient germinants [L-valine, L-alanine, and tryptic soy broth (TSB)], nisin, and incubation at atmospheric pressure (37°C). The most effective combinations for Bacillus subtilis resulted in a reduction of culturable dormant spores by 8 log10 units. The combinations involved nisin, a nutrient germinant (L-valine or TSB), a first vHP treatment (550 MPa, 60°C, 2.5 min), incubation at atmospheric pressure (37°C, 6 h), and a second vHP treatment (550 MPa, 60°C, 2.5 min). Such treatment combination with L-valine reduced Bacillus amyloliquefaciens spores by only 2 log10 units. B. amyloliquefaciens, thus, proved to be substantially more HP-resistant compared to B. subtilis, validating previous studies. Despite combining different germination mechanisms, complete germination could not be achieved for either species. The natural bacteriocin nisin did seemingly not promote HP germination initiation under chosen HP conditions, contrary to previous literature. Nevertheless, nisin might be beneficial to inhibit the growth of HP-germinated or remaining ungerminated spores. Future germination experiments might consider that nisin could not be completely removed from spores by washing, thereby affecting plate count enumeration. IMPORTANCE Extremely resistant spore-forming bacteria are widely distributed in nature. They infiltrate the food chain and processing environments, posing risks of spoilage and food safety. Traditional heat-intensive inactivation methods often negatively affect the product quality. HP germination-inactivation offers a potential solution for better preserving sensitive ingredients while inactivating spores. However, the presence of ungerminated (superdormant) spores hampers the strategy's success and safety. Knowledge of strategies to overcome resistance to HP germination is vital to progress mild spore control technologies. Our study contributes to the evaluation and development of mild preservation processes by evaluating strategies to enhance the HP germination-inactivation efficacy. Mild preservation processes can fulfill the consumers' demand for safe and minimally processed food. [ABSTRACT FROM AUTHOR]

In order to identify the pathogenic bacteria causing walnut rot disease, the pathogenic bacteria were identified through tissue isolation and pathogenicity tie-back, and the species identification was completed based on morphological characteristics combined with molecular biology. Furthermore, the effects of three types of immune-inducers spray as well as five types of biologicals and two types of adjuvants scraping were compared on walnut rot. Fifteen strains were isolated from 14 diseased branch samples, of which 14 strains were identified morphologically and molecularly as Cytospora chrysosperma, and one strain was Cryptosphaeria pullmanensis. Therefore, the main causal agent of walnut rot disease in Hetian County was C. chrysosperma. Among the three kinds of immune-inducing antagonists, 0.5% chitosan AS 200× and amino-oligosaccharide AS 500x showed better- inducing effects of 51.43% and 45.47%, respectively. Among the biological agents, the control effects of 100 billion CFU/g Bacillus amyloliquefaciens WP 700x + 99% SK Enspray 99 EC 200× and 3% Zhongshengmycin AS 500x + 99% SK Enspray 99 EC 200× were better, 92.31% and 84.61%, respectively. This study clarified the pathogen of walnut rot disease in Hetian County and provided a reference for the biological control of walnut rot disease in the field. [ABSTRACT FROM AUTHOR]

To enhance the nutritional value of Acanthopanax senticosus leaves (AL), a fermentation process was conducted using a probiotic Bacillus mixture, and the changes in chemical constituents and biological activities before and after fermentation were compared. A response surface methodology was employed to optimize the liquid fermentation conditions of AL based on their influence on polyphenol content. Non-targeted metabolomics analysis was performed using LC-MS/MS to reveal the differing profiles of compounds before and after fermentation. The results indicated that Bacillus subtilis LK and Bacillus amyloliquefaciens M2 significantly influenced polyphenol content during fermentation. The optimal fermentation conditions were determined to be a fermentation time of 54 h, a temperature of 39.6 °C, and an inoculum size of 2.5% (v/v). In comparison to unfermented AL, the total polyphenol and flavonoid contents, as well as the free radical scavenging capacities measured by DPPH and ABTS assays, and the activities of β-glucosidase and endo-glucanase, were significantly increased. The non-targeted metabolomics analysis identified 1348 metabolites, of which 829 were classified as differential metabolites. A correlation analysis between the differential metabolites of polyphenols, flavonoids, and antioxidant activity revealed that 13 differential metabolites were positively correlated with antioxidant activity. Kyoto encyclopedia of genes and genomes (KEGG) enrichment analysis of the differential metabolites identified 82 pathways, with two of the top 25 metabolic pathways related to flavonoids. This study explores the potential for enhancing the active ingredients and biological effects of AL through probiotic fermentation using Bacillus strains. [ABSTRACT FROM AUTHOR]

Simple Summary: Providing high-quality feeds is required to maintain goat kids' health and improve their growth performance during their early growth phase, such as milk protein, fish meal, or extruded feed. The present study demonstrates that supplementation with 2% fermented feather meal–soybean meal product in the diet can promote the growth of goat kids by improving crude protein digestibility, diarrhea status, and immunity: therefore, it can completely replace the fish meal as a starter. These findings provide potential for practices of nutrition and immunity in goat kids, benefiting the livestock industry. This study investigates the effects of replacing fish meal with fermented feather meal–soybean meal product (FFSMP) from Bacillus amyloliquefaciens CU33 in the starter on growth performance, relative health performance, and digestibility of Alpine goat kids. In trial 1, thirty-two Alpine goat kids (male) were randomly assigned to dietary supplementation of 2% feather meal–soybean meal mix (FSM), 2% fish meal, or replacing fish meal with 50% or 100% FFSMP (FFSMP-50 or FFSMP-100) in starter (n = 8). In trial 2, sixteen goat kids were selected after trial 1 and used in this digestion trial which began from 12 weeks old. The treatments were the same as in trial 1 (n = 4). In trial 1, the growth performance of the FFSMP groups was better than the FSM group at 0 to 10 weeks (p < 0.05). The fecal consistency index of the FFSMP-100 group was better than the FSM group at 0 to 5 weeks and 5 to 10 weeks. In trial 2, the crude protein (CP) digestibility of the FSM group decreased (p < 0.05). In conclusion, dietary supplementation with 2% FFSMP in goat kids' diets can improve the growth performance, the CP digestibility, and diarrhea status, and it can completely replace the fish meal in starter diets. [ABSTRACT FROM AUTHOR]

Societal Impact Statement Summary The use of chemical plant protection products must be reduced to promote sustainability in food production. One possible alternative is biological control agents (BCAs), but their efficacy under commercial conditions does not always reach the standard of chemical control agents. Previously, light has been found to induce mechanisms in bacterial BCAs that can affect their distribution and establishment. This could promote BCA efficacy. We looked into how monochromatic and polychromatic (which is what growers use) light treatments affected the occurrence of three BCAs post‐application. By combining two non‐chemical methods: a biological (BCA) and a cultural (light) control method, this offers a new integrated pest control strategy. The dynamics and functionality of beneficial and non‐beneficial, non‐phototrophic bacteria can be influenced by light quality. We investigated if light could aid the survival of three bacterial biological control agents (BCAs; Bacillus amyloliquefaciens DSM7, Pseudomonas chlororaphis 50083 and Streptomyces griseoviridis CBS904.68) in the canopy of greenhouse‐grown tomatoes at four light treatments. Tomato plants were exposed to 50 μmol m−2 s−1 of either polychromatic light (white) or monochromatic light (blue: 420 nm, green: 530 nm and red: 660 nm) using DYNA LED lamps for a total of 48 h post foliar application of the BCAs. Leaves were harvested from two levels in the canopy at the top and middle of each plant at 0, 2, 4, 8, 12, 24 and 48 h post inoculation. The occurrences of the BCAs were quantified by plate count and droplet digital PCR (ddPCR). S. griseoviridis persisted under most treatments, whereas P. chlororaphis and B. amyloliquefaciens preferred the polychromatic and green light treatments as depicted by the viable count analyses. Significant differences between the DNA and cDNA concentrations were only noted for P. chlororaphis, with prominent wavelength effects. Light exposure dose, placement in the canopy and wavelength were found to be decisive factors for BCA re‐isolation, indicating that they have different optimal light environments. [ABSTRACT FROM AUTHOR]

The cyclic lipopeptide bacillomycin D exhibits potent antifungal activity against a wide range of fungi, particularly filamentous fungi, thereby exhibiting significant potential for application in food preservation. However, the limited yield obtained from wild strains hinders the practical application of bacillomycin D. In this study, we used different strategies to modify the original strain Bacillus amyloliquefaciens fmbJ, including promoter replacement, competitive synthetic gene knockout, and overexpression of the lipopeptide transporter gene. Subsequently, we analyzed changes in the production and expression of bacillomycin D genes in the engineered strain. The results demonstrated that P bacA exhibits the highest promoter activity, leading to a significant increase (2.05-fold) in bacillomycin D production compared with control group. Additionally, deletion of the epsA- O gene cluster also significantly enhances the synthesis of bacillomycin D. However, when amyloid gene cluster t asA-sipW-yqxM was deleted,bacillomycin D accumulation time was shortened, resulting in no significant increase in bacillomycin D production. In addition, lipopeptide transporters SwrC, KrsE and YcxA did not promote bacillomycin D production. Finally, by replacing the promoter P bacA , we successfully disrupted the epsA -O gene cluster, and bacillomycin D production increased by 2.55 times compared to the initial bacillomycin D strain. In conclusion, this study indicated that genetic engineering of regulatory genes was an effective strategy to improve the yields of bacillomycin D and provided promising strains for industrial production of bacillomycin D. [Display omitted] • The Bacillomycin D, as an antimicrobial lipopeptide. • Effect of promoter replacement on bacillomycin D synthesis. • Effect of competing pathway gene knockout on bacillomycin D synthesis. • Effect of lipopeptide transporter overexpression on bacillomycin D synthesis. • Production of bacillomycin D in superimposed engineered bacteria. [ABSTRACT FROM AUTHOR]

Biologically active compounds are key-important ingredients of tomato fruits, especially those produced by organic agricultural practices. Being biologically effective soil treatments, microbial inoculants can improve soil quality through a variety of mechanisms. Their activity can influence soil properties and plant development, thereby determining the quantity and quality of the crop. However, little research was done on how these inoculants affect the nutritional quality of the tomato fruit and on the antioxidant status of the fruits. This study investigated lycopene content and total antioxidant capacity of organically grown tomato fruits (Solanum lycopersicum L. var. 'Mobil') using various types of single and combined bioeffector products in two growing seasons. Single inoculation contained Trichoderma harzianum, plant growth promoting Pseudomonas sp., and phosphorus-mobilizing Bacillus amyloliquefaciens strains. The combined treatment consisted of biotic Trichoderma harzianum, Pseudomonas fluorescens, and Bacillus subtilis strains with abiotic micronutrients of zinc and manganese. Sum of ranking differences method, as a multicriteria optimization method, was used to rank the treatments and identify the ones deviating the least from the reference treatment. The results showed that all microbial soil inoculants positively affected tomato lycopene content. The combined treatment showed significantly higher lycopene content than the Control in both years. We found that weather and climate conditions also greatly influence the total antioxidant capacity. Based on our results, we recommend the use of combined bioeffective treatments to improve the food quality value of tomato fruits. [ABSTRACT FROM AUTHOR]

Introduction: Casuarina equisetifolia is a common protective forest in coastal areas. However, artificial C. equisetifolia forests cannot self-renew, mainly due to the accumulation of allelochemicals. Endophytic bacteria may alleviate the root growth inhibition caused by allelochemicals in C. equisetifolia seedlings. B. amyloliquefaciens and B. aryabhattai were endophytic bacteria with strong allelopathy in C. equisetifolia root. The allelopathy mechanism of these two endophytes and their interaction with C. equisetifolia remains to be studied. Methods: Whole-genome sequencing of B. amyloliquefaciens and B. aryabhattai isolated from the roots of allelochemical-accumulating C. equisetifolia was performed using Illumina Hiseq and PacBio single-molecule sequencing platforms. Sterile seedlings of C. equisetifolia were treated with either individual or mixed bacterial cultures through root drenching. Transcriptional and metabolomics analyses were conducted after 3 days of infection. Results and discussion: Whole-genome sequencing of Bacillus aryabhattai and Bacillus amyloliquefaciens showed that the two strains contained various horizontal gene transfer elements such as insertion sequence, prophage and transposon. In addition, these two strains also contain numerous genes related to the synthesis and catabolism of allelochemicals. After these two strains of bacteria were individually or mixed infected with C. equisetifolia, metabolomics and transcriptomic analysis of C. equisetifolia showed the 11 important secondary metabolite biosynthesis among them alkaloids biosynthesis, phenylpropanoid and terpenes biosynthesis and related genes were putatively regulated. Correlation analysis revealed that 48 differentially expressed genes had strong positive correlations with 42 differential metabolites, and 48 differentially expressed genes had strong negative correlations with 36 differential metabolites. For example, CMBL gene showed positive correlations with the allelochemical (-)-Catechin gallate, while Bp10 gene showed negative correlations with (-)-Catechin gallate. Conclusion: The intergenerational accumulation of allelochemicals may induce horizontal gene transfer in endogenic bacteria of Casuarina equisetifolia root. Endophytic Bacillus plays an allelopathic role by assisting the host in regulating gene expression and the production and/or variety of allelochemicals. This comprehensive study sheds light on the intricate genetic and metabolic interactions between Bacillus endophytes and C. equisetifolia. These findings provide insights into endophyte-mediated allelopathy and its potential uses in plant biology and forest sustainability. [ABSTRACT FROM AUTHOR]

The crude metabolic extract from plant biocontrol bacteria plays a very important role in sustainable agricultural production. These extracts help maintain healthy plants and have very important application prospects in biotechnology related to alleviating apple replant disease (ARD). In this study, Bacillus velezensis XC1 (T1), Bacillus amyloliquefaciens QSB-6 (T2), and Lactobacillus reuteri LBR (T3) were examined to characterize the ability of their crude metabolic extracts to alleviate ARD. The high-throughput sequencing data of the soil microbial community structure were analyzed in relation to LBR crude metabolic extracts, and an extensive untargeted metabolomic analysis of UHPLC-Qex active components was performed. Active LC-MS/MS revealed that the main secondary metabolites involved in the biological control exerted by L. reuteri included 3-hydroxypropionaldehyde, extracellular polysaccharides (EPS), p-hydroxybenzoic acid, and azelaic acid. These crude metabolic extracts significantly inhibited the growth of soil pathogenic fungi, reduced the abundance of Fusarium, promoted the abundance of beneficial bacteria such as Pseudomonas, and optimized the soil microbial community structure. Improved modern extraction and purification technologies will be able to offer additional insights into the mechanism of action of these secondary metabolites and enable them to be used in biological preparations to prevent and control ARD in the future, as well as to allow harmful chemical fumigants to be discontinued. [ABSTRACT FROM AUTHOR]

In order to assessing the heterogeneity of Bacillus sp. isolates spoilage potential, six Bacillus sp. isolates isolated from spoiled low-temperature sausages were used to investigate the heterogeneity of their spoilage properties at 20 °C (room temperature) and 37 °C (optimum growth temperature). The growth curve, acid production capacity, gas production capacity, protease activity, lipase activity, and amylase activity of six strains of Bacillus sp. were measured in the experiment. The results revealed that Bacillus cereus (C) had the greatest capacity for producing acid and that after 48 hours at 37 °C, the pH in the culture medium dropped by 0.71 relative to the blank control group. Following a 5-day culture at 37 °C, Bacillus amyloliquefaciens (G) displayed the greatest protease and amylase activities, with a maximum protease activity of 7.17 U/mL and a decomposition circle area of starch agar of 16.53 cm². Bacillus cereus (C) exhibited the least comprehensive spoiling ability, as evidenced by its protease activity of 2.63 U/mL and the decomposition circle area of starch agar of 7.55 cm2 after 5 days of culture at 37 °C. Furthermore, it was discovered that the growth temperature significantly impacted the spoilage potential of the strains. In summary, there was great heterogeneity in the spoilage characteristics of Bacillus sp.. When examining its spoilage traits, it is important to consider this heterogeneity. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Agro-Environment Science is the property of Journal of Agro-Environment Science Editorial Board 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.)

When a plant is infected by a pathogen, endogenous immune responses are initiated. When the initiation of these defense responses is induced by a pathogen-associated molecular pattern (PAMP) of a pathogen, it is called PAMP-triggered immunity (PTI). Previous studies have shown that Bacillus amyloliquefaciens PMB05 can enhance PTI signals and improve disease control of bacterial soft rot and wilt in Arabidopsis thaliana. In the context of controlling bacterial wilt disease, the involvement of a mitogen-activated protein kinase (MAPK) signaling pathway has been established. Nevertheless, it remains unclear whether this pathway is also required for B. amyloliquefaciens PMB05 in controlling bacterial soft rot. In this study, A. thaliana ecotype Columbia (Col-0) and its mutants on a MAPK pathway-related pathway were used as a model and established that the ability of B. amyloliquefaciens PMB05 to control soft rot requires the participation of the MAPK pathway. Moreover, the enhancement of disease resistance by PMB05 is highly correlated with the activation of reactive oxygen species generation and stomata closure, rather than callose deposition. The spray inoculation method was used to illustrate that PMB05 can enhance stomatal closure, thereby restricting invasion by the soft rot bacterium. This control mechanism has also been demonstrated to require the activation of the MAPK pathway. This study demonstrates that B. amyloliquefaciens PMB05 can accelerate stomata closure via the activation of the MAPK pathway during PTI, thereby reducing pathogen invasion and achieving disease resistance against bacterial soft rot. [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]

The utilisation of enzymes in the industry has brought numerous benefits and advantages to production processes. Enzymes serve as biocatalysts, efficiently catalyzing reactions and hydrolysis in biochemical processes. However, there are challenges in applying enzymes in the industry, particularly concerning enzyme stability. The obstacle encountered in the production processes involving industrial enzyme applications is the low stability of enzymes when used at high temperatures. Heat-sensitive enzymes undergo damage or denaturation. Thermophilic microorganisms are chosen because they hold the potential to produce thermophilic enzymes. The thermophilic enzymes exhibit better heat stability compared to other enzymes, making them an effective alternative for future industrial production processes. This study aims to isolate thermotolerant bacteria from Nglimut Hot Spring sediment, screen for cellulase- and amylase-producing isolates, and molecularly identify the best isolate using 16S rRNA barcode. The results show that 22 bacterial isolates were found in the sediment of a hot spring; TS-14 was the best isolate in producing amylase, with the highest average amylolytic index of 2.38, whereas TS-15 had the highest cellulolytic index of 2.11. Based on 16S rRNA identification, TS-14 showed an homological identity of 79% with Bacillus amyloliquefaciens, while TS-15 had a 100% homological identity with Bacillus licheniformis. These results were important as the first step of screening bacterial potential to produce thermophilic enzymes that could be applied in the downstream processing in future industrial and biotechnology companies. [ABSTRACT FROM AUTHOR]

This study has isolated, characterized, and identified potential plant growthpromoting rhizobacteria (PGPR) with multiple PGP characteristics (N2-fixation, P- and K-solubilization, IAA, and siderophores production) from the rhizosphere BRIS soil of Acacia mangium. A total of 24 pure colonies were isolated and only 8 colonies were selected for further evaluation of the growth rate in 5% organic molasses medium supplemented with 2% KNO3. Based on the biochemical, potential PGP characteristics and growth performance, 3 superior PGPR strains were selected and identified as Paraburkholderia unamae (UA1), Bacillus amyloliquefaciens (UA6), and Enterobacter asburiae (UAA2) by partial sequencing of the 16S rRNA gene. The selected bacterial strains either in single or mixed (UA1 + UA6 + UAA2) cultures have shown a significant biochemical estimation of the PGP characteristics. Each strain has its own PGPR traits superiority with UA1 showing the best PGP characteristic followed by UA6 and UAA2. The use of mixed bacterial strains was beneficial as it showed the best performance in N2-fixation, siderophores production, and significant effect on corn phenology, growth and yield compared to using a single strain. These types of microbes showed potential to be used as biofertilizer and should be exploited more. [ABSTRACT FROM AUTHOR]

Seven auxin-producing endophytic bacterial strains (Azospirillum spp., Methylobacterium symbioticum, Bacillus spp.), and two different combinations of these strains were used to verify their influence on tomato during germination and development in hydroponic conditions where, as a novelty for Canestrino di Lucca cultivar, endophytic bacteria were inoculated. To emphasize the presence of bacterial auxins in roots and stems of seedlings, both in situ staining qualitative assessment and quantitative analysis were carried out. Moreover, hypogeal and epigeal growth of the plantlets were measured, and correlation analyses were conducted to examine the relationship between the amount of indolacetic acid (IAA) produced by the bacterial strains and root and stem parameters. Plantlets treated with microbial inoculants showed a significant increase in the survival rate compared to the control treatment. The best results as IAA producers were from Azospirillum baldaniorum Sp245 and A. brasilense Cd, which also induced significant root growth. On the other hand, Bacillus amyloliquefaciens and B. licheniformis induced the best rates in stem growth. These findings highlight the potential for using endophytic bacterial strains in a hydroponic co-cultivation system that enables inoculating plantlets, at an early stage of growth (5 days old). [ABSTRACT FROM AUTHOR]

Simple Summary: Comparing different commercial biofertilizer products for their effects as biostimulants, as protectors of plants from drought and plant-pathogenic fungi, can be difficult due to the increasing number of bacteria available in the market. Using a panel of tests, we compared the effects of four commercial strains of the operational group Bacillus amyloliquefaciens to assess their ability to protect pepper plants and stimulate their growth. Then, we obtained numerical values that allow quick diagnoses when choosing a product to ensure that it has the greatest added value or when describing a new strain. The market for bacteria as agricultural biofertilizers is growing rapidly, offering plant-growth stimulants; biofungicides; and, more recently, protectors against extreme environmental factors, such as drought. This abundance makes it challenging for the end user to decide on the product to use. In this work, we describe the isolation of a strain of Bacillus velezensis (belonging to the operational group Bacillus amyloliquefaciens) for use as a plant-growth-promoting rhizobacterium, a biofungicide, and a protector against drought. To compare its effectiveness with other commercial strains of the same operational group, Bacillus amyloliquefaciens, we analyzed its ability to promote the growth of pepper plants and protect them against drought, as well as its fungicidal activity through antibiosis and antagonism tests, its ability to solubilize potassium and phosphates, and its ability to produce siderophores. Finally, we used a probit function, a type of regression analysis used to model the outcomes of analyses, to quantify the biostimulatory effectiveness of the different plant-growth-promoting rhizobacteria, developing what we have called the Agricultural Protection Against Stress Index, which allowed us to numerically compare the four commercial strains of the operational group Bacillus amyloliquefaciens, based on a Delphi method—a type of regression analysis that can be used to model a cumulative normal distribution—and integrate the results from our panel of tests into a single value. [ABSTRACT FROM AUTHOR]

This scientific article presents a study on the optimization of temperature and fermentation time for the production of an antifungal extract from Bacillus amyloliquefaciens B17. Experiments were used to determine the optimal fermentation conditions, and a crude extract was obtained that showed antifungal activity against various phytopathogenic fungi. The optimal concentrations of the extract that inhibited the radial growth of the studied fungi, as well as its effect on the germination of the fungi spores, were determined. Additionally, the production of antifungal lipopeptides by the B. amyloliquefaciens B17 strain and its potential as biocontrol agents in agriculture are discussed. [Extracted from the article]

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]

One of the major problems related to climate change is the increase in land area affected by higher salt concentrations and desertification. Finding economically and environmentally friendly sustainable solutions that effectively mitigate salt stress damage to plants is of great importance. In our work, some natural products and microbial biocontrol agents were evaluated for their long-term effectiveness in reducing salt stress in lettuce (Lactuca sativa L. var. romana) plants. Fourteen different treatments applied to soil pots, with and without salt stress, were analyzed using biometric (leaf and root length and width), physiological (chlorophyll and proline content), and morphological (microscopic preparations) techniques and NGS to study the microbial communities in the soil of plants subjected to different treatments. Under our long-term experimental conditions (90 days), the results showed that salt stress negatively affected plant growth. The statistical analysis showed a high variability in the responses of the different biostimulant treatments. Notably, the biocontrol agents Papiliotrema terrestris (strain PT22AV), Bacillus amyloliquefaciens (strain B07), and Rahnella aquatilis (strain 36) can act as salt stress mitigators in L. sativa. These findings suggest that both microbial biocontrol agents and certain natural products hold promise for reducing the adverse effects of salt stress on plants. [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.)

The objective of this study was to identify effective agents for the prevention and control of ginseng Sclerotinia root rot disease caused by Sclerotinia nivalis. The inhibitory effects of 16 chemical fungicides and 10 biocontrol agents (strains) on mycelial growth and sclerotium formation in S. nivalis were determined using a plate confrontation essay. The results showed that the best chemical agents for inhibiting the mycelial growth and sclerotium formation of S. nivalis were fluconazole and fludioxonil, while Bacillus amyloliquefaciens FS6 and B. subtilis (Kono) were the best biocontrol agents (strains). The results of field trials in 2022 and 2023 showed that the control effects of fluconazole and fludioxonil on ginseng Sclerotinia root rot disease were 90.60–98.16%, and those of the biocontrol agents B. amyloliquefaciens FS6 and B. subtilis (Kono) were 94.80–97.24%, respectively. Chemical agents produced abnormal and twisted mycelia, while the biocontrol agents increased mycelial branching, dilated the mycelium tip, and revealed an abnormal balloon. All of the fungicides decreased the ergosterol content, changed the cell membrane permeability, and increased the protein and nucleic acid permeability. These results suggest that these are potential agents for controlling ginseng Sclerotinia root rot disease, and their biochemical mechanisms of chemical and biocontrol of this disease were demonstrated. [ABSTRACT FROM AUTHOR]

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]

In this investigation, 396 endophytic bacterial strains from six indigenous medicinal plant species within the Xinjiang Tumor Peak National Nature Reserve were subjected to screening. The strain MR4 emerged as a noteworthy contender, demonstrating pronounced biocontrol capabilities coupled with exceptional cold tolerance. Through morphological scrutiny and comprehensive genomic sequencing, MR4 was identified as Bacillus amyloliquefaciens. Antagonistic assays revealed MR4's efficacy in suppressing the causative agents of cotton wilt and verticillium wilt, achieving inhibition rates surpassing 50%. Analyses, underpinned by PCR methodologies, indicated MR4's capacity to biosynthesize a minimum of eight distinct antimicrobial agents. The whole-genome sequencing data indicated that B. amyloliquefaciens MR4 had the genome size and GC content of 4,017,872 bp and 47.14%, respectively, and 4191 coding genes were identified. The genome consists of a single chromosome and one plasmid. Moreover, it was augmented by annotations from various databases, including GO, KEGG, and COG. The pathogenicity of MR4 undergoes evaluation, while predictions concerning MR4's secondary metabolites have disclosed gene clusters for 13 varieties of these compounds, with particular emphasis on surfactins and fengycin. Comparative analyses with four paradigmatic strains shed light on MR4's genomic composition and its phylogenetic lineage within the Bacillus genus. The genomic data pertaining to MR4 have been duly submitted to the NCBI GenBank, bearing the accession numbers CP146236 (Chr1) and CP146237 (plas1). This study endeavors to furnish potent microbial resources for the biocontrol and enhancement of plant growth, thereby providing a theoretical groundwork for MR4's agronomic utilization. [ABSTRACT FROM AUTHOR]

Objectives: To enhance the de novo synthesis of SAM, the effects of several key genes on SAM synthesis were examined based on modular strategy, and the key genes were manipulated to obtain an engineered strain with high SAM production. Results: In Bacillus amyloliquefaciens HSAM6, the deletion of argG gene to block aspartic acid branching degradation increased SAM titer to 254.78 ± 15.91 mg/L, up 18% from HSAM6. Subsequently, deleting the moaA gene to boost the supply of 5-methyltetrahydrofolate led to the stunted growth and the plummeting yield of SAM. Further improvement of strain growth by overexpression of the citA gene, while SAM synthesis was not significantly enhanced. Finally, the maximum SAM titer (452.89 ± 13.42 mg/L) was obtained by overexpression SAM2 gene using the multicopy plasmid. Conclusions: The deletion of argG gene and the overexpression of SAM2 gene significantly improved SAM synthesis in B. amyloliquefaciens. [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.

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]

The purpose of this experiment was to optimize the process of probiotics solid-state fermentation on stems and leaves of Angelica pubescens Radix, and to increase the content of osthole in stems and leaves of Angelica pubescens Radix. In this experiment, Bacillus amyloliquefaciens strain SSYB was used to ferment the stems and leaves of Angelica pubescens Radix, and on the basis of single factor test, the solid-state fermentation process was optimized by orthogonal experimental design, and the content of osthole in stems and leaves of Angelica pubescens Radix before and after the fermentation process was determined by high performance liquid chromatography. The results showed that the optimized fermentation process of stems and leaves of Angelica pubescens Radix was fermentation time of 72 h, fermentation temperature of 37 ℃, inoculation amount of 5%, and water content 65%. Under these conditions, the content of osthole in stems and leaves of Angelica pubescens Radix was 1.81 mg/g, which was significantly higher than that before fermentation by 45.97% (P<0.01). The results show that the content of osthole in stems and leaves of Angelica pubescens Radix is increased by optimizing the solid-state fermentation process of Bacillus amyloliquefaciens SSYB. [ABSTRACT FROM AUTHOR]