Aims: To characterize xylanolytic enzyme producing strains of Bacillus subtilis from the intestinal tract of a cabbage looper (Trichoplusia ni (Hübner)) larvae. Methodology and results: Approximately 5 g of intestinal content from the instar larvae were homogenated and serially diluted 10-4 -10-6 times with sterile normal saline before being spread onto duplicate tryptic soy agar plates. Every different colony was selected to test for xylanase production. Of six isolates, only one was found to be positive for xylanase production by screening agar. Biochemical characteristics and 16S rRNA gene sequencing indicated that the Bact-I was closely related to Bacillus subtilis. Optimization of xylanase enzyme production showed that Bacillus subtilis was able to produce xylanase enzymes when grown in a culture medium containing 2% (w/v) corn stover and 0.6% (w/v) yeast extract at pH 10 and 37 °C. The xylanase gene was cloned and characterized. The result revealed that the xylanase gene of Bacillus subtilis was homology to the β-1,4 endo-xylanase gene. Conclusion, significance and impact of study: A xylanase producing Bacillus subtilis was isolated from the intestinal tract of a cabbage looper (Trichoplusia ni (Hübner)) larvae. Optimization and evaluation of the xylanase activity of Bacillus subtilis indicated that it could be useful for xylanase production or as a probiotic for improving animal feed stuff.
Bacillus subtilis

Biochemical characteristics of B. subtilis Du, B. subtilis NT, B. subtilis ATCC 6633 were primarily the same, but their size was smaller with small colonies, R form and opaquely white color. 72 hours was culture duration for obtaining highest amount of amylase in B. subtilis ATCC, while in B. subtilis NT and B. subtilis Du – 96 hours
Bacillus ; Bacillus subtilis ; Biochemistry

The supplementation of oligo-alginate with molecular weight of 4.700 Dalton at the concentration of 30-50 ppm has made the biomass of Bacillus subtilis increased visibly.
bacillus subtilis ; bacteria ; water

In the last 11 years recently the contaminated rate was very low (291/6382 samples). 0.45% and decreased dramatically in the past 3 years (2000-2003 period). The most common contaminated germs were primarily gram(+) bacteria (60% - 195/320 samples). 4.6% of samples were contamined with fungi (15/320), which should be erradicated completely
Biochemistry ; Bacillus subtilis ; Probiotics

Probiotic preparations of Bacillus subtilis (B. subtilis) have been used by humans to treat and prevent the common forms of diarrhea caused by bacteria and virus, as well as other infections. To develop preparations of B. subtilis as an intranasal form, the authors studied the persistence and the antirhinopharyngitis of B. subtilis given nasally to mice. Substantial numbers of B. subtilis were still present in the nasopharynx 6 days after inoculation. The reduction in bacterial growth was similar to the positive controls. Also a reduced histopathological score was evident in corresponding with treating by ampicillin and prednisolone. Specifically, the authors obtained superior results in mice having administration of a dose of B. subtilis a day before inoculation of S. pneumoniae
Sinusitis ; Bacillus subtilis ; Therapeutics

Aim: DNA molecular size markers or DNA ladders play a vital role in molecular biology laboratories where DNA electrophoresis experiments are usually conducted. This study aimed to produce a 100 bp DNA ladder at laboratory scale, which could be applied to determine the size of DNA fragments in molecular biology experiments. Methodology and results: In this study, 14 primers including 4 forwards and 10 reverses were designed based on the 16S rRNA gene sequence of Bacillus subtilis. These primers were able to amplify 10 DNA fragments with accurate sizes from 100 to 1000 bp. Furthermore, touchdown PCR was involved to maximize the specificity and yield of PCR products. Ten DNA fragments with the sizes including 100, 200, 300, 400, 500, 600, 700, 800, 900 and 1000 bp were synthesized, and such bands were equivalent with commercial DNA ladders. Moreover, the quantity and quality of PCR products were measured using a nanodrop spectrophotometer. The optimal concentration ratios between such fragments (100- 1000 bp) were 800, 300, 150, 150, 500, 50, 50, 50, 50 and 50 (ng/µL), respectively. These ratios showed the clear and high resolution on 1.5% agarose gel. Conclusion, significance and impact of the study The results indicated that 16S rRNA gene of B. subtilis was a potential material for DNA ladder preparation due to the multiple copies number of this gene. Furthermore, in combination with touchdown PCR, the nonspecific bands were reduced, and the products could be used directly without the need of purification step.
Bacillus subtilis--genetics

Based on the transcriptome analysis data of a Bacillus licheniformis, a novel bidirectional promoter was identified from the strain and its transcriptional strength was analyzed. The expression level of a Bacillus clausii derived alkaline protease gene driven by the bidirectional promoter was studied by using the known strong constitutive promoter pShuttle-09 as a control. Three recombinant expression vectors and the corresponding recombinant bacteria were constructed. Under the control of the new promoter pLA and its reverse promoter pLB, the alkaline protease expression level respectively reached 164 U/mL and 111 U/mL. The results indicated that the transcription strength of pLA was significantly higher than that of pShuttle-09 and pLB, and both the pLA and pLB promoters could initiate the expression of the alkaline protease. Thus, it provides a new expression element for the heterogenous genes in Bacillus sp. and a new idea for the co-expression of two genes in one prokaryotic strain.
Bacillus subtilis ; Promoter Regions, Genetic

Biosynthesis of nanomaterials has attracted much attention for its excellent characteristics such as low energy consumption, high safety, and environmental friendliness. As we all know, the toxic selenite can be transformed into higher-value nanomaterials by using bacteria. In this study, nano-selenium was synthesized by halophilic Bacillus subtilis subspecies stercoris strain XP in LB medium supplemented with selenite (electron acceptor). The physicochemical characteristics of nano-selenium were analyzed by scanning electron microscope (SEM), X-ray energy dispersive spectral analysis (EDAX), X-ray diffraction (XRD), and fourier transform infrared spectroscopy (FTIR). Meanwhile, the antifungal activity of nano-selenium to strawberry pathogens (fusarium wilt, erythema, and purple spot fungi) was determined. The products from reduction of selenite by strain XP was amorphous spherical selenium nanoparticles (SeNPs) with a diameter range of 135-165 nm. The production of SeNPs was positively correlated with time (0-48 h) and no changes were observed on cell morphology. Selenium was dominant in the surface of SeNPs where the organic elements (C, O, N, and S) existed at the same time. SeNPs were coated with biomolecules containing functional groups (such as -OH, C=O, N-H, and C-H) which were associated with the stability and bioactivity of particles. Although the highest concentration of SeNPs had significant (P<0.05) inhibitory effects on three strains of strawberry pathogens, antifungal activity to erythema and fusarium wilt pathogenic fungi was higher than that to purple spot pathogenic fungi from strawberry. In conclusion, strain XP not only has strong tolerance to high salt stress, but can be also used to synthesize biological SeNPs with good stability and biological activity. Thus, the strain XP has bright perspectives and great potential advantage in pathogens control and green selenium-rich strawberry planting as well as other fields.
Bacillus subtilis ; Fragaria ; Nanoparticles ; Selenious Acid ; Selenium

Microcystis aeruginosa, a type of algal bloom microalgae, is widely distributed in water, causing serious deteriorated effects on humans and the ecological environment. As a biocontrol microorganism, Bacillus subtilis can synthesize various bioactive substances through non-ribosomal peptide synthetase, to inhibit the growth of M. aeruginosa. Thus, it is imperative to investigate the non-ribosomal peptide (NRP) metabolites of B. subtilis fmb60. Three NRP metabolites from B. subtilis fmb60 including bacillibactin, surfactin and fengycin were extracted and identified by genome mining technology. The growth inhibition of M. aeruginosa was studied by adding various concentrations of NRP metabolites. The half-effect concentration value (EC50.4 d) of M. aeruginosa was 26.5 mg/L after incubation for 4 days. With the increasing concentration, the inhibitory effects of NRP metabolites of B. subtilis fmb60 on M. aeruginosa was enhanced significantly. Compared with the control group, with the addition of 50 mg/L NRP metabolites to the M. aeruginosa, the content of Fv/Fm, Fv/Fo and Yield parameter after cultured for 4 days were decreased by 2.8%, 1.7% and 2.0%, respectively. Those findings indicate that the NRP metabolites of B. subtilis fmb60 can significantly inhibit the photosynthesis and metabolism of M. aeruginosa, which provides a theoretical foundation for the development of biological algae inhibitor of B. subtilis.
Bacillus subtilis ; Humans ; Microcystis ; Peptides ; Photosynthesis

The ability of Bacillus subtilis, strain ALICA to produce three mycolytic enzymes (chitinase, β-1,3-glucanase, and protease), was carried out by the chemical standard methods. Bacillus subtilis ALICA was screened based on their antifungal activity in dual plate assay and cell-free culture filtrate (25%) against five different phytopathogenic fungi Alternaria alternata, Macrophomina sp., Colletotrichum gloeosporioides, Botrytis cinerea, and Sclerotium rolfesii. The B. subtilis ALICA detected positive for chitinase, β-1,3-glucanase and protease enzymes. Fungal growth inhibition by both strain ALICA and its cell-free culture filtrate ranged from 51.36% to 86.3% and 38.43% to 68.6%, respectively. Moreover, hyphal morphological changes like damage, broken, swelling, distortions abnormal morphology were observed. Genes expression of protease, β-1,3-glucanase, and lipopeptides (subtilosin and subtilisin) were confirmed their presence in the supernatant of strain ALICA. Our findings indicated that strain ALICA provided a broad spectrum of antifungal activities against various phytopathogenic fungi and may be a potential effective alternative to chemical fungicides.
Alternaria ; Bacillus subtilis* ; Bacillus* ; Botrytis ; Chitinase ; Colletotrichum ; Fungi* ; Lipopeptides ; Prosopis*