Abstract: The sheath blight disease of rice caused by Rhizoctonia solani is widely prevalent and one of the most destructive diseases, affecting rice cultivation and loss worldwide. In the present study, a set of twenty Bacillus isolates from saline soil of Uttar Pradesh were tested for their biocontrol activity against R. solani with the aim to obtain a potential strain for the control of sheath blight disease toward ecofriendly and sustainable agriculture. The results of dual-culture assay and scanning electron microscopic studies showed that the strain RH5 exhibited significant antagonistic activity (84.41%) against the fungal pathogen R. solani. On the basis of 16S rDNA sequencing analysis, the potential biocontrol strain RH5 was identified as Bacillus subtilis. Furthermore, the strain RH5 was characterized by different plant growth-promoting (PGP) activities and induction of defense-related enzymes in rice plants against R. solani. The strain RH5 posses various PGP attributes (indole acetic acid, siderophore, hydrogen cyanide production and phosphate, Zn, K solubility), hydrolytic enzymatic (chitinase, protease, cellulase, xylanase) activity, and presence of antimicrobial peptide biosynthetic genes (bacylisin, surfactin, and fengycin), which support the strain for efficient colonization of hyphae and its inhibition. Finally, the results of the greenhouse study confirmed that strain RH5 significantly increased plant growth and triggered resistance in rice plants through the production of defense-related antioxidant enzymes.

Abstract: In the present study, 133 bacterial isolates from 11 composted aromatic plant wastes were selected for their ability to inhibit the mycelial growth of the soil-borne phytopathogenic fungi Sclerotinia minor and Rhizoctonia solani. Successively, a subset of 35 from them were further characterized for their ability to control, in vivo, rocket damping-off caused by the two fungi. Moreover, the isolates were characterized for morphology of the colonies, Gram reaction, siderophore production, P-solubilization and for the presence of antimicrobial lipopeptide genes in the genome. The screening for the in vitro antagonisms showed a mycelial growth reduction ranging between 31.7% and 56.1% for R. solani and 34.4% and 59.4% for S. minor. All the isolates were not able to produce siderophores and some of them were able to solubilize P. The isolates contained two or more of the five lipoproteins coding genes investigated in this study. The most promising isolates were identified at species level by 16S-rRNA partial gene sequence analysis and were grouped in two main clusters related to Bacillus subtilis and Bacillus amyloliquefaciens reference strains. Results indicated that Bacillus isolates from compost are good candidates for application in the biocontrol of cultivated plants.

Abstract: Aims Plant tissues are the reservoirs of beneficial and harmful microbes that regulates plant growth. In the present study, we investigated the diversity, function and colonization of sugarcane roots associated with Bacillus spp. Methods and results A total of 20 Bacillus strains were isolated and identified by 16S rRNA gene sequencing, and their genetic diversity was examined by BOX, ERIC, REP, (GTG)5 PCR techniques. Among all Bacillus isolates, 65% showed indole acetic acid-like compounds production, 50% solubilized phosphorus and 25% of the isolates were able to secrete siderophore. Moreover, all 20 Bacillus isolates showed antifungal activity against eight fungal pathogens and 11 of them (55%) antagonized tomato grey mold. Based on the plant growth-promoting traits and antifungal potential, isolate Y8 was selected for root and plant tissue colonization assays and a greenhouse-level sugarcane growth promotion study. Fluorescence microscopy results confirmed that isolate Y8 has a strong ability to colonize in the sugarcane root and leaves, and the root surface association of Y8 was confirmed by scanning electron microscopy. Furthermore, greenhouse experimental results demonstrated that Y8 has a significant effect on enhancing sugarcane biomass and root length. Conclusions Endophytic Bacillus strains have growth-promoting properties and anti-fungal ability that can enhance plant fitness in an eco-friendly manner. Significance and impact of the study Endophytic Bacillus strains would be a potential alternative to chemical fertilizer as well as a biocontrol agent in the future.

Abstract: Bacillus based probiotics are becoming relevant as alternatives to antibiotics used in poultry production and in other animal husbandry. This study describes the isolation of 48 Bacillus spp. candidates, from chickens and chicken environments, for use as potential probiotics in poultry production. These isolates, plus a further 18, were tested in a comprehensive in vitro screening regime that was specifically designed to select the best isolates that satisfied multiple modes of action desirable for commercial poultry probiotics. This screening programme involved the evaluation of the ability of the isolates to survive and grow in the limiting conditions of the chicken gastrointestinal tract. Only 11 of the isolates fulfilled these criteria; hence, they were further evaluated for the ability to adhere to epithelial cells, produce extracellular enzymes, and to demonstrate antagonistic activity against selected pathogens of significant importance in poultry production. Of these, a total of 6 isolates were selected, due to their all-round probiotic capability. Identification by 16S RNA sequencing confirmed these isolates as B. subtilis and B. velezensis, identities which are generally regarded as safe. The Bacillus isolates reported in our study exhibit strong all-inclusive probiotic effects and can potentially be formulated as a probiotic preparation for poultry production.

Abstract: The present study was conducted to identify the two Pseudomonas syringae pv. syringae strains attained from the citrus blast infected tissues and also to find out the antimicrobial potentiality of plant extracts and antagonistic bacteria Bacillus spp. both under in vitro and in vivo conditions. Based on the microscopic observation and biochemical features including colouring, magnitude, size, and form of colonies displayed on LB medium, we speculate that ps17a and ps18a strains were similar to P. syringae pv syringae. For molecular identification, 16S rRNA and multi-locus sequence analysis (MLSA) with two housekeeping gene (rpoD and gyrB) sequences indicated an identical pattern to the corresponding sequences of other P. syringae pv. syringae strains which confirmed that a genetically homologous species of P. syringae pv. syringae was responsible for bacterial blast disease of citrus cultivars. Later, PCR amplification using two primer pairs (B1 and B2) yielded 752-bp fragments to confirm that syrB gene present on both isolated P. syringae pv syringae and reference strains (Pss16) can synthesize syringomycin, a potent toxin for plant pathogenicity induction. Based on the pathogenicity tests, two strains were similar in terms of virulence activity, however, were not analogous thus, having the same level of severity effect to induce bacterial blast. Moreover, antibiotic sensitivity assay showed disproportionate result for both strains which resemble susceptible strains determination. From the in vitro investigation of six plant extracts and three Bacillus isolates against ps17a and ps18a, the ethanolic extract of Allium sativum, Moringa oleifera, and Azadirachta indica showed the highest antibacterial activity against two isolated bacterial strains up to inhibition zone 23.4, 24.4 and 18.2 mm in diameter, respectively while Bacillus isolates proved to be better natural antimicrobial agents against the disease. Finally, based on in vivo experiment, the most effective plant extracts and antagonistic isolates BS5 exhibited significant necrosis growth reduction after 10 weeks of inoculation by ps17a up to 67.48 and 52.88% as compared to 65.42 and 55.3% by ps18a, respectively. Thus, six selected ethanolic plant extracts and three isolates of Bacillus spp. have a broad-spectrum antimicrobial activity which can be used as effective biocontrol agent.

Abstract: Plasmid-mediated colistin resistance (PMCR) is a global public health concern, given its ease of transmissibility. The purpose of this study was to evaluate two methods for the detection of PMCR from bacterial colonies: (i) the NG-Test MCR-1 lateral flow immunoassay (LFA; NG Biotech, Guipry, France) and (ii) the EDTA-colistin broth disk elution (EDTA-CBDE) screening test method. These methods were evaluated using a cohort of contemporary, clinical Gram-negative bacillus isolates from 3 U.S. academic medical centers (126 isolates of the Enterobacterales, 50 Pseudomonas aeruginosa isolates, and 50 Acinetobacter species isolates; 1 isolate was mcr positive) and 12 mcr-positive CDC-FDA Antibiotic Resistance (AR) Isolate Bank isolates for which reference broth microdilution colistin susceptibility results were available. Eleven (4.6%) isolates were strongly positive by the MCR-1 LFA, with an additional 8 (3.4%) isolates yielding faintly positive results. The positive percent agreement (PPA) and negative percent agreement (NPA) for MCR-1 detection were 100% and 96.1%, respectively. Upon repeat testing, only a single false-positive MCR-2 producer remained, as the isolates with initially faintly positive results were negative. The EDTA-CBDE screening method had an overall PPA and NPA of 100% and 94.3%, respectively. The NPA for the EDTA-CBDE method was slightly lower at 94.2% with Enterobacterales, whereas it was 96.0% with P. aeruginosa The MCR-1 LFA and EDTA-CBDE methods are both accurate and user-friendly methods for the detection of PMCR. Despite the rarity of PMCR among clinical isolates in the United States, these methods are valuable tools that may be implemented in public health and clinical microbiology laboratories to further discern the mechanism of resistance among colistin-resistant Gram-negative isolates and to detect PMCR for infection prevention and control purposes.

Abstract: Mantchoua is a fermented seed condiment produced from kapok tree (Ceiba pentandra) seeds in Burkina Faso. In this study, the microbiology of Mantchoua from raw material to final product was investigated in samples from two production sites (Po and Bobo-Dioulasso). Four processing methods of Mantchoua production were characterized by determination of numbers of Aerobic Mesophilic Bacteria (AMB), Bacillus spp. and pH. A total of 251 Bacillus spp. from 619 AMB isolates were identified using M13-PCR and ITS-PCR typing, 16S rRNA and gyrA gene sequencing. AMB and Bacillus spp. counts in raw material ranged between 4.2-4.7 log10 CFU/g and 3.8-4.1 log10 CFU/g in kapok seeds and between 2.2-2.3 log10 CFU/g and 1.1-1.8 log10 CFU/g in ash lye solution, respectively. Microbial counts in seeds mash during fermentation ranged between 9-10.9 log10 CFU/g for AMB and between 8.6-10.5 log10 CFU/g for Bacillus spp. In dried Mantchoua, AMB counts ranged between 7.7-10.4 log10 CFU/g while Bacillus spp. counts ranged between 7.5-10.3 log10 CFU/g. The fermentation of Mantchoua involved different species of Bacillus spp. At Bobo-Dioulasso pilot plant, B. subtilis subsp. subtilis dominated (50% of the Bacillus isolates) followed by B. cereus sensu lato (28% of the Bacillus isolates) while at Po traditional production site, B. cereus sensu lato dominated (54% of the Bacillus isolates) followed also by B. subtilis subsp. subtilis (26% of the Bacillus isolates). For the Mantchoua processes including ash lye solution, pH were consistently higher during fermentation (pH 8.6-8.9), and the number of isolated B. cereus sensu lato were lower.

Abstract: In this study, a novel culture medium that simulates shrimp pond conditions was established to screen nitrite-degrading isolates. The medium was supplemented with nitrite as a nitrogen source and shrimp feed as the major carbon source, to achieve the high nitrogen and low carbon nutritional status found in shrimp farming ponds. Screening using this medium identified potent denitrifying Bacillus isolates, among which Bacillus subtilis M7-1 was considered best. M7-1 was able to completely degrade nitrite-N in 24 h without much consumption of dissolved oxygen. Efficient denitrification activity took place in liquid cultures within a set of non-stringent ranges of pH (5.0-9.0), salinity (0-30) and temperature (25-35℃). The denitrifying enzyme gene was amplified, se-quenced and further identified as nirS type. In biosecurity assessments, M7-1 had no negative effects on shrimps at a dose of 106cfu mL−1. M7-1 could therefore be used in aquaculture to reduce and control the nitrogen concentration, and to promote the development of sustainable and healthy culture systems.

Abstract: In our study, soil samples from the rhizosphere of various uncultivated weeds were collected from fifteen different locations of Gujarat. Heat treatment was given at 65°C for 20 minutes prior to initial screening for spore-forming Bacilli spp. Among them, 20 nitrogen-fixing (NFB), 27 phosphate solubilizing (PSB) and 15 potassium mobilizing (KMB) isolates were screened primarily. After molecular identification only Bacilli isolates were further selected and characterized. Three superior Bacillus isolates were selected from each category by secondary screening. All three isolates for nitrogen fixation were found nif positive, while Bacillus megaterium (NAUN2) showed maximum 2.04 µmol/ml ammonia production followed by Bacillus sp. (NAUN1) and Lysinibacillus macroides (NAUN3) with 0.64 and 0.99 µmol/ml, respectively. Bacillus sp. (NAUP1) gave maximum 401.94 µg/ml phosphate solubilization on Pikovaskya broth media after third day while Bacillus sp. (NAUP2) and Brevibacillus sp. (NAUP3) showed 376.74 and 308.16 µg/ml phosphate solubilization, correspondingly. Lysinibacillus macroides (NAUK2) showed maximum 228.14 µg/ml potassium mobilization on Aleksandrov after the twentieth day while Lysinibacillus macroides (NAUK1), Bacillus megaterium (NAUK3) and Bacillus sp. (NAUP1) had effective 196.91, 158.18, 59.33 µg/ml potassium mobilization, respectively. Interestingly, no selected Bacilli isolates from the consortia were found to have inhibitory effect on other isolates in compatibility test. Out of the nine Bacillus isolates NAUK1, NAUK2, NAUK3 were found to be effective against rice pathogen Magnaportha oryzae on PDA plates. All the nine isolates were checked for IAA and siderophore production. Isolate NAUN1, NAUP3, NAUK1, NAUK2 and NAUK3 showed 37.2%, 17.9%, 33.6%, 38.9%, 48.2% siderophore production on CAS medium after 72 hrs, respectively. Isolate NAUP3 showed maximum 146.68 µg/ml IAA production while NAUN1, NAUN3, NAUP1, NAUK2 and NAUP2 showed 99.37, 99.37, 114.57, 101.46, 93.48 µg/ml IAA production, respectively after the seventh day. Rice seeds were inoculated with individual isolate and different Bacilli consortia, which significantly improved growth parameters as compared to control in pot study after 60 days of sowing. 100% RDF + NPK consortia gave significantly increased root length (11.65%), shoot length (10.28%), no. of leaves (17.39%), leaf area (11.68%) and chlorophyll content in leaf (4.76%). Similar trends were observed when the data was compared with absolute control. The spore forming Bacilli consortia was able to survive a wide range of temperature and pH fluctuations and found effective N-fixers, P-solubilizers, K-mobilizers, siderophore producers, IAA producers with antagonistic activity against rice pathogen Magnaportha oryzae.

Abstract: The objective of this study was to construct a rapid, high-throughput, and biosafety-compatible screening method for Bacillus anthracis and Bacillus cereus based on matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS). MALDI-TOF MS coupled to ClinProTools was used to discover MALDI-TOF MS biomarker peaks and generate a classification model based on a genetic algorithm (GA) to differentiate between different Bacillus anthracis and Bacillus cereus isolates. Thirty Bacillus anthracis and 19 Bacillus cereus strains were used to construct and analyze the model, and 40 Bacillus strains were used for validation. For the GA screening model, the cross-validation values, which reflect the ability of the model to handle variability among the test spectra, and the recognition capability values, which reflect the model's ability to correctly identify its component spectra, were all 100%. This model contained 10 biomarker peaks (m/z 3,339.9, 3,396.3, 3,682.4, 5,476.7, 6,610.6, 6,680.1, 7,365.3, 7,792.4, 9,475.8, and 10,934.1) used to correctly identify 28 Bacillus anthracis and 12 Bacillus cereus isolates from 40 Bacillus isolates, with a sensitivity and specificity of 100%. With the obvious advantages of being rapid, highly accurate, and highly sensitive and having a low cost and high throughput, MALDI-TOF MS ClinProTools is a powerful and reliable tool for screening Bacillus anthracis and Bacillus cereus strains.

Abstract: Problems in decreasing coffee production one of them caused by plant pests attack. Countermeasures using pesticides and disinfectants are not effective because they have long effects and ruining the environment also pest resistance. It is necessary to prevent a more environmentally friendly way by utilizing a natural enemy in the form of a microorganism, the genus Bacillus. Lipase can hydrolyze lipids so that it can be used to degrade lipid substrates that compile the body structure of pests and diseases. This research aims to detect the lipolytic activity of Bacillus isolates from coffee plantations. The results of this research obtained 3 isolates of Bacillus namely T1, T2, and T3 which have differences in cell configuration and variations in the location of endospores. Furthermore, Bacillus isolates were detected lipolytic activity by growing isolates on lipase selective medium. Isolates that have the largest lipolytic activity are T2 isolate codes with an average index of 6.01 and the lowest lipolytic activity, namely, isolate T1 codes with an average index of 4.58.

Abstract: The aim of the present work was to isolate Bacillus spp. With high lipase activity; to characterize the isolates using both biochemical and molecular methods; to produce lipase using Bacillus isolates and to study the biochemical and biophysical characteristics of the produced lipase. Sixty five Bacillus isolates were isolated from soil 20 isolates from guar field soil (G), 15 isolates from Abusabein field soil (B), 15 isolates from sun flower field soil (S) and 15 isolates from oil effluent (O). Lipase producing isolates were screened; a Chromogenic plate’s method was used. Enzyme activity was quantitatively assayed. Lipase production under submerged fermentation (SMF) conditions using a production medium that contained metal salts, Tween-20 and olive oil as substrate at different period 24, 48, 72 and 96 h, the optimum pH, temperature for lipase activity was determinated and kinetics as well. The isolates showed the highest lipase activity which was identified as Bacillus sp. The optimum pH, temperature, thermostability and kinetic of the produced enzymes were found in three isolates G14, O1 and B10 with the highest enzyme activity and best stability. The isolates G14, O1 and B10 revealed the highest lipase activity of 63.4, 41.2 and 28.3 U/ml, respectively. The results showed optimum pH of the lipase activity from isolates G14, O1 and B10 8.0, 6.0 and 6.0 and the optimum temperature 40, 60 and 75˚C, respectively. Lipase enzymes from isolates O1 and B10 were found to be more thermostable after incubation time for 120 min at 90˚C. The Vmax and Km values of lipase for isolates G14, OI and B10 were 17.6, 135 and 24.4 μmole∙min𕒵 and 1.3, 1.6 and 0.681 mM, respectively. According to these results Bacillus spp. with high lipase activity and thermostability can be used to promote food, pharmaceuticals, paper, detergents agrochemicals industries and pollution control in Sudan.

Abstract: Black scurf disease caused by Rhizoctonia solani is a main yield limiting factor for potato tuber production as it leads to plant death. The present study aimed to isolate naturally occurring antagonistic bacteria that could control R. solani. Bacillus sp. was selected among of 84 isolates secured from rhizosphere of healthy potato plant based on its ability to suppress the growth of the pathogen R. solani. Phylogenetic analysis of this strain based on 16S rRNA gene sequences showed highest similarity (99%) with Bacillus sp.; it was deposited in the GenBank under the accession number of MK030136. The strain culture filtrate containing protease, diffusible antibiotic, hydrogen cyanide and siderophore was capable of inhibiting growth of the pathogen up to 15 days compared to 7 and 10 days for other Bacillus isolates. It also produces indole acetic acid which promoted plant growth. Morphological and structural changes that took place as a result of Bacillus sp. and R. solani interaction were evaluated using light, scanning and transmission electron microscopies. The results showed that Bacillus sp. caused loss of structural integrity, abnormal coiling, shriveling and lysis of the R. solani hyphae, in addition to complete cytoplasm and internal organelles depletion. The Bacillus sp. under study was immobilized on nanoclay to form a bionanocomposite, which was stable and exhibited the biocontrol efficiency along 8 months storage. Both in vitro and greenhouse experiments showed high inhibition of R. solani radial growth. Results indicate that the prepared bionanocomposite is a promising alternative to the commercial products.

Abstract: Here, we present the draft genome sequences of two Bacillus strains, HF117_J1_D and USDA818B3_A, isolated in Pomona, California, from the gastrointestinal (GI) tract of backyard and commercial broiler chickens, respectively. The draft genomes of both strains appear to represent novel species.

Abstract: Chemotaxis is the movement of a single cell organism as a reaction to a chemical stimulation in its surrounding environment. Biofilm-forming bacteria are the cause for numerous major health and environmental problems. Bacterial extracts were proven to induce negative chemotaxis reaction against biofilm-forming bacteria and biofilm development. Therefore, using and enhancing these extracts are considered as promising methods in pharmaceutical production and environmental science. In this study, twenty Bacillus isolates and five biofilm-forming bacteria (targeted bacteria) isolates from different water and sediments samples of different areas in Basra province were biochemically diagnosed. Secondary metabolites of Bacillus isolates were extracted and analysed. Total proteins in the extracts were determined using Biuret method and the highest two isolates (BS8) and (BS14) with 13.78 and 12.02 g/l protein, respectively were chosen for the experiment. GC-MS results showed the existence of compounds with proven high antimicrobial properties such as type D-amino acids, N-cyclopropyl carbonyl-, butyl and esters such as d- proline, N-methoxycarbonyl, and pentyl ester. Afterwards, the chemotaxis nature of the purified extracts was studied. The results showed that both extracts had a negative chemotaxis toward the targeted bacteria represented by transparent halos without bacterial growth around the spot where secondary metabolites extracts of Bacillus subtilis were placed. K. kristinae was the most affected species in regards of growth inhibition zone diameter with 23 and 24 mm for (BS8) and (BS14) extracts respectively, while P. aeruginosa was the least affected with 19 and 18 mm for (BS8) and (BS14) extracts respectively.

Abstract: Post-harvest shrimp losses are a big problem due to the proliferation of spoilage bacteria. Presence and multiplication of these bacteria promotes the emergence of food-borne diseases. This study was carried out to characterize some spoilage bacteria from tropical brackish water shrimps and black tiger shrimps stored in ambient temperature (25 °C). 22 isolates of Bacillus spp; 09 isolates of Coagulase Negative Staphylococci (CNS) and 04 isolates of enterobacteria such as Pantoea spp (01); Serratia plymutica (01) and Serratia rubidaea (02) have been identified. Resistance and virulence genes were then detected. All isolates expressed resistance to at least three of antibiotics tested. 03 isolates of enterobacteria were susceptible to cetfazidim and amoxicillin-clavulanic acid. Bacillus spp showed total susceptibility to cefixim, ertapenem and cetfazidim. Staphylococci were susceptible to clindamycin. Pantoea spp was resistant to all antibiotics but exhibited intermediate susceptibility to amoxicillin-clavulanic acid. 04 isolates of Staphylococci were positive to mecA resistances genes. All the enterobacteria harbor no tetracycline resistance genes. All the isolates of Bacillus exhibited the presence of enterotoxin genes. Also, a high prevalence of 21 isolates to hemolytic enterotoxins was noted. 17 isolates from them kept ability to cell-lyse factor production like sphingomyelinase activities. The majority of Bacillus isolates identified by the present study poses a potential risk of food poisoning due to the prevalence of toxin genes found.

Abstract: The effect of nine isolates of Bacillus amyloliquefaciensand one strain of Trichoderma harzianum, TR, on mycelial growth and germination of Colletotrichum acutatum were studied. The nine isolates were identified as Bacillus amyloliquefaciens. The efficacy of isolates was tested, at different concentrations. Results showed that one Bacillus isolates (Bc2) and TR were more effective at the lower concentration tested (3 × 105 CFU/ml and 105 conidia/ml).

Abstract: Applicability of ammonia bioremediation by efficient bacterial isolates was investigated under static batch culture conditions. Bacillus aerius (M.1), Bacillus bingmayongensis (M.2) and Bacillus toyonensis (M.3) were isolated from the Inlet of El-Bahr El-Saedy drinking water treatment plant, Rosetta Branch, Egypt and identified based on their morphological, cultural and biochemical characteristics. Identification of these isolates via genomic 16S rRNA sequencing technique was also performed. To optimize ammonia removing process, effect of some environmental conditions (pH, temperature and ammonia concentrations) were tested. Results indicated that a pH of 6.5 and 7.0, and the temperature between 30 and 35oC were the most optimal values for removing ammonia by the three tested isolates. Ammonia was consumed effectively during the first five incubation days, indicating maximum consumption rate, but it was reduced to its lowest level 25 days after incubation. Ammonia consumption rates were increased by increasing its concentration for all tested isolates, indicating growth activation and no substrate inhibition. Ammonia consumption rate by the ternary mixture reached its maximum of 1.60 mg Lday five days after incubation, and then reduced slowly to 0.38 mg L day 25 days after incubation. It indicated sequential and synergistic effects between the isolates in their ternary mixture during the removal of ammonia.

Abstract: The present invention provides Bacillus isolates, as well as probiotic and animal feed compositions comprising said isolates, which may be included in the diet of poultry to improve growth performance with reduced energy diets. Methods of using these compositions to improve nutritional uptake or to reduce the incidence of footpad dermatitis in poultry are also provided.

Abstract: The present study was conducted to determine the field efficacy of Pseudomonas and Bacillus spp., isolated from the rhizosphere of healthy papaya to manage papaya ringspot virus disease (PRSVD), when applied as isolate-mixtures along with their effect on plant defense enzyme activity. Mixtures of bacterial isolates were applied by two methods, namely seed soak (SS) and soil drench (SD) to field-grown and naturally-infected papaya plants (var. Red Lady). Disease severity and fruit yield were quantified over a period of six months and defense-related enzyme activity in leaves was quantified with spectrophotometry. At the sixth month after transplanting, SS-treated plants with the mixture of Bacillus isolates and the combined mixture of Pseudomonas and Bacillus isolates showed a significantly lower % disease index on foliage than the plants under control and the Pseudomonas mixture treatments. A significantly lower % disease index was shown on the fruits treated with all the bacterial treatments applied by both methods, in comparison to the untreated control. Mixture of Pseudomonas isolates and the combined treatment with Pseudomonas and Bacillus isolates, when applied as the SS method, gave significantly higher fruit yield than that of the control treatment. Activities of peroxidase and phenylalanine ammonia lyase were significantly higher in plants treated with the mixture of Pseudomonas isolates by SS method while β-1,3-glucanase activity was significantly higher when applied the same treatment by SD method. Findings revealed the ability to reduce severity of PRSVD and induce defense-related enzymes when mixtures of Pseudomonas and Bacillus spp. were applied under field conditions.

Abstract: The use of bacteria as a biological control agent in aquaculture is such new hope overcoming the negative impacts of the impropriate use of antibiotics. Bacillus is widely known as a potential probiotic for aquaculture, especially which are derived from aquatic biota. Due to a concern that the role of Bacillus as a probiotic agent will be disrupted by residues of antibiotics in the water, this research aimed to identify Bacillus species from common carp intestine based on the molecular method and investigate their resistance to some com-mercial antibiotics that widely used in aquaculture. Chloramphenicol, ampicillin, and metronidazole were used to determine the Bacillus resistance to antibiotics using the Kirby Bauer method. The resistance assay was carried out with a bacterial density of 10 8 CFU/mL. The results showed that Bacillus isolates derived from common carp intestine were closely related and resistant to antibiotics. Isolates that resistant to the three types of antibiotics were Cc.1.9 (CgN9) and Cc.2.18 (CgM18).

Abstract: Bacterial wilt caused by Ralstonia solanacearum is one of the most devastating diseases in tomato cultivation. This study aimed to evaluate the effect of Bacillus and Trichoderma isolates to manage the bacterial wilt disease. Field experiments were conducted in a randomized complete block design at Mwea and Kabete sites in Kenya. The treatments included 3 Trichoderma; 2 Bacillus isolates; a mixture of T1, T2, and T4; chemical standard; and distilled water as control. Trichoderma and Bacillus isolates were grown on sterilized sorghum grain and cow manure carriers respectively. Antagonist’s inoculation was carried out by dipping tomato plants for 30 min in each treatment suspension. Each treatment was then applied at a rate of 150 ml/plant hole and this was repeated after 35 days. All the treatments significantly reduced bacterial wilt incidence and severity at P ≤ 0.05 than the control at both sites. Trichoderma isolate T1, followed by Bacillus isolate CB64, was the best in reducing the disease incidence by more than 61.66 and 53%, respectively at both sites. Treatment CB64 and T1 had the highest reduction of R. solanacearum population in the soil by 93.17 and 92.07%, respectively. However, control had a pathogen increase of 20.40%. CB64 and T1 performed significantly better compared to the standard, while the mixture of isolates T1, T2, and T4 performed the poorest in all parameters. The treatments also increased the yield of tomato. Results from this study showed that Trichoderma and Bacillus isolates are effective biological control agents for use in management of bacterial wilt.

Abstract: Probiotic bacteria mainly Lactic Acid Bacteria (LAB) demonstrate to equilibrate the intestinal microflora. Strains of the Bacillus species have been extensively used as probiotics for human beings, animal feed as well as plant promoting bacteria. Attempts were made to characterize and assess the safety of Bacillus strains for their putative virulence factors. The present study includes screening the isolates by hemolysis on blood agar, DNase, lecithinase and cytotoxic activity as well as detection of toxins in the culture medium. PCR technique was used to detect genes encoding enterotoxin T (bceT), cytotoxin K (CytK), enterotoxin FM (EntFM), non-hemolytic enterotoxin (NheA, NheB), haemolysin BL (HblA, HblC, HblD) and emetic toxin (ces). Among seven Bacillus isolates, only isolates B. cereus sp. M14, B. subtilis sp. M12 and B. methylotrophicus sp. M8 showed weak hemolysis on blood agar. DNase and lecithinase activity were not observed for all isolates. However, isolates B. subtilis sp. M12 and B. cereus sp. M14 indicated low cytotoxic effects on HepG2 cell line. Using two commercial immunoassay kits, no enterotoxin was detected for all isolates. Nhe and Hbl genes were detected in isolates B. methylotrophicus sp. M8 and B. cereus sp. M14, respectively. In contrast, none of the Bacillus isolates harbored bceT, entFM and ces genes in their chromosomes. Taking together, among the evaluated Bacillus isolates, strains B. pumilus sp. M17 and B. pumilus sp. S10 found to be the most promising candidates to fulfill the safety assessments of putative virulence factors suitable for human consumption.

Abstract: A total of 117 Bacillus strains were isolated from Miang, a culture relevant fermented tea of northern Thailand. These strains were collected from 16 sampling sites in north Thailand. In this collection 95 isolates were tannin-tolerant Bacillus capable of growth on nutrient agar supplemented with 0.5% (w/v) total tannins from tea leaves extract (TE). The strains were also positive for pectinase, xylanase and amylase activity, while 91 and 86 isolates were positive for cellulase and β-mannanase, respectively. Only 21 isolates producing extracellular tannase were selected for further characterization. Identification by 16S rRNA gene sequence analysis revealed that more than 50% (11 of 21 isolates) were Bacillus tequilensis, whereas the remaining were B. siamensis (3), B. megaterium (3), B. aryabhattai (3) and B. toyonensis (1). B. tequilensis K34.2 produced the highest extracellular tannase activity of 0.60 U/mL after cultivation at 37 °C for 48 h. In addition, all 21 isolates were resistant to 0.3% (w/v) bile salt, sensitive to gentamicin, erythromycin, vancomycin and kanamycin and also tolerant to acidic condition. Cell hydrophobicity varied from 9.4 to 80.4% and neutralized culture supernatants of some Bacillus isolates showed bacteriocin producing potentiality against Samonella enterica serovar Typhimurium TISTR 292. All tested probiotic properties indicated that B. tequilensis K19.3, B. tequilensis K34.2 and B. siamensis K19.1 had high probiotic potential. This is the first report describing tannin-tolerant Bacillus and their extracellular tannase producing capability in Miang, a traditional fermented tea of Thailand.

Abstract: Xylan is one of the most abundant polysaccharides present in softwoods and hardwoods. Microbial xylanases mainly mediate its degradation. Xylanase has biotechnological potential with enormous demand in industries. The present study was initiated to investigate the diversity of culturable bacteria in mangrove sediments of Goa (India) and study the xylanase-coding gene in the isolated bacteria. Phylogenetic diversity was determined, in which proteobacteria was the dominant phylum (57%) with the abundance of Vibrio (36%) and Photobacterium (9%), while the second most abundant phylum Firmicutes (40%) was dominated by Bacillus (32%). Among all the culturable isolates screened for xylan degradation, the Bacillus genus was dominant (86%) xylan degrader. Bacillus isolates were further screened for the xylanase gene. The xylanase gene fragments of representative Bacillus were sequenced. All sequences matched to glycoside hydrolase (GH) family 10, thus, showing the dominance of GH10 xylanases in the mangroves regions of Goa (India). GH10 xylanases isolated from Bacillus sp. showed a broad pH optima ranged from pH 5.0 to 9.0 and temperature optima ranged from 50 to 60°C. These properties can be of potential interest for a variety of industrial processes where degradation of lignocelluloses is a crucial process.

Abstract: Probiotics can act as biological control agents against bacterial infection in aquatic animals, and also increase growth and stimulate immunity. In this study, two potential probiotics, Bacillus sp. KUAQ1 and Bacillus sp. KUAQ2, isolated from Nile tilapia Oreochromis niloticus Linn. intestine, were investigated for their biological functions. Species of isolated bacteria were identified by a conventional microbiological assay, biochemical assay and 16S ribosomal RNA polymerase chain reaction analysis. Both Bacillus isolates could survive at a pH ranging from 2 to 9 for 6 h and for 2 h in bile salts. The candidate probiotics were tested for their inhibition activity against the pathogenic bacteria Streptococcus agalactiae and Aeromonas hydrophila, and their specific protease activity. The probiotics had no significant effect (P > 0.05) on the average weight, average daily growth, specific growth rate or feed conversion ratio of tilapia fry after an 8-week feeding trial. Furthermore, supplementation with probiotics did not increase the survival rate of tilapia challenged with S. agalactiae. Several immune parameters including lysozyme, phagocytic activity and respiratory burst activity of juvenile fish treated with probiotics were significantly higher than those of the control (P 0.05). Stress tolerance to brackish water at 25 p.p.t. NaCl did not improve significantly in fish treated with probiotics (P > 0.05). These two probiotic Bacillus offer benefits in terms of disease control and stimulation of the immune response of cultured tilapia.

Abstract: Rocky tomato seeds variety was treated with endophytic Bacillus isolates to determine their efficacy and ability to enhance seedling vigour and germination per cent as a potential plant growth promoter. Twelve screened endophytic Bacillus isolates were evaluated for their germination and vigour of tomato seeds in in vitro condition. Seed germination percent ranged between 60-95% with lowest in uninoculated control. Among them, Bacillus velezensis ERBS51 treated seeds had the highest germination per cent (95%) and vigour index (1073.50 and 1472.5) at both 7th and 14th day which was the best performing isolate among the twelve. Bacillus sp. ERBS10 also gave significant good result with 88% germination per cent along with 953 and 1287 vigour indexes at 7th and 14th days. The root length and shoot length were also found higher in both the isolates. The result indicates that Bacillus velezensis ERBS51 was found most effective in enhancing plant growth.