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Oceniano aktywność mutagenną 7 nowo zsyntetyzowanych kationowych substancji powierzchniowo czynnych (KSPC) przy zastosowaniu testu genotoksyczności na Bacillus subtilis. Wykazano, że w badanych stężeniach związki te nie wykazywały aktywności mutagennej.
A study was conducted to determine the Production of cellulase and pectinase enzyme by using Plant growth promoting rhizobacteria like Pseudomonas fluorescence and Bacillus subtilis. These to micro organism are isolated by serial dilution method. One gram of soil sample was diluted in to 10 ml of sterile distilled water and 1 ml of sample solution was serially diluted in 9ml of sterile water up to 10 dilution. Each sample from dilution 10-5 and 10-6 were taken and streaked in to KB and NA medium and incubate at 24 hrs. After 24 hrs Pseudomonas fluorescence and Bacillus subtilis was observed in the medium of KB and NA medium. Both the culture was sub cultured and maintain in the same for the further work. CMCase medium was prepared and sterilized by autoclave for 121 ºC for 15 minutes after sterilization these medium contain petriplate was streaked by bacteria and incubates for 48h after incubation period a clear halo zone was produced by these bacteria among these bacteria Pseudomonas fluorescence are able to produce high amount of cellulose compare to Bacillus subtilis. Pectin agar medium was prepared and sterilized by autoclave for 121 ºC for 15 minutes after sterilization these medium contain petriplate was streaked by bacteria incubates for 48h after incubation period a clear halo zone was produced by these bacteria, among these bacteria Pseudomonas fluorescence are able to produce high amount of Pectinase compare to Bacillus subtilis. Plant growth promoting rhizobacteria (PGPR) are beneficial bacteria that colonize plant roots and enhance plant growth by a wide variety of mechanisms.
The soil sample was collected from the paddy field of Sriperumbudur, Tamilnadu which is having a history of repeated pesticide applications. The isolation of efficient pesticide degrading bacteria was identified as Pseudomonas aeruginosa, Staphylococcus aureus and Bacillus subtilis. The growth of the three pesticide degrading isolates was assessed in Minimal salt broth containing 25 ppm of pesticides. Two popularly used pesticides Metribuzin and Profenofos were selected for this study. Among the three bacterial isolates, the bacteria Bacillus subtilis utilized the pesticides effectively and showed maximum growth. The growth of the three pesticides degrading isolates Pseudomonas aeruginosa, Staphylococcus aureus and Bacillus subtilis was assessed in Minimal salt broth containing 25 ppm of pesticides at different temperature levels (25 °C, 30 °C, 35 °C, 40 °C, 45 °C, 50 °C & 55 °C) and pH levels (pH 4, pH 5, pH 6, pH 7 & pH 8) and carbon sources (Lactose, Dextrose, Fructose, Mannose & Galactose) and nitrogen sources Peptone, Yeast extract, Beef extract, Malt extract and Casein respectively. The maximum growth rate of bacteria was recorded at 35 °C and pH 6. The maximum growth of bacteria was in the presence of Dextrose followed by Fructose, Galactose and Mannose. The least growth was recorded in Lactose broth culture. The maximum growth of bacteria was in the presence of Malt extract followed by Peptone, Yeast extract and Casein. The least growth was recorded in Beef extract broth culture. The bacterial isolates showed maximum growth in the Minimal salt broth containing Profenofos followed by Metribuzin.
Bacteriostatic activity expressed by MIC values of S. aureus 209P was compared with MIC values for B. subtilis 6633 on 26 propolis extracts. Extracts with different MIC values ranging from a 0.060 to 0.600 mg/ml basis were tested. The determined MIC values for both species of bacteria were found to be identical in 19 samples of propolis extracts. Small differences in MIC values were observed in 7 samples. The differences did not exceed 0.010 mg/ml in 3 and 0.020 mg/ml of medium in 4 samples. The results showed that for the determination of bacteriostatic activity of propolis extracts the application of B. subtilis 6633 yielded an identical value to S. aureus 209P.
Three strains of microorganisms: Bacillus subtilis, Serratia liquefaciens and Escherichia coli were tested as whole-cell biocatalysts for the kinetic resolution of isomers of two new phosphonoacetic acid derivatives. Used compounds possess two chiral centres – one at the carbon adjacent to both functional groups and the other at the phosphorus. Biocatalytic hydrolysis of 2-butyryloxy-2-(butoxyetoxyphosphinyl)acetic acid and 2-butyryloxy-2-(isobutoxyetoxyphosphinyl) acetic acid with whole cells of Bacillus subtilis produced corresponding hydroxyphosphonates with diastereoselectivity ranging from 50 to 60%.
The purpose of the study was to evaluate the effectiveness of preservation of two bacteria strains: Bacillus subtilis B-3 and Bacillus poly my xa В-20 (proteinase and amylase producers) in the form of dried spores on glass beads. In our study we have found that the survival level of the two strains after 15 months of storage was 100%. The viability of B. subtilis B-3 was 20% lower than that of the control culture maintained by subculturing on agar slants and stored at 4°C (µ = 1.8 h-1 and µ = 2.16 h-1), whereas the viability of B. polymyxa B-20 was similar to that of the control culture (µ = 1.3 h-1). The biosynthetic capability of B. polymyxa B-20 remained at unchanged levels of 303 FSU and 2.5 AU, but only when the spores had been stored on glass beads with starch as the protective agent. The biosynthetic activity of B. subtilis B-3 was 76% lower in the case of proteinases and 60% lower in the case of amylases. The method of storage of bacteria in the form of spores dried on glass beads, described in this paper, can be recommended for B. polymyxa B-20 strain, but it is not suitable for B. subtilis B-3 since the bacteria have lost, to a large extent, their biosynthetic ability.
The changes of the composition of growing medium and the fatty acid composition of Bacillus subtilis PO270, a bacterium isolated from the wheat rhizosphere, was evaluated during different phases of growth. During growth alkalinity reaction of medium was observed and in late stationary phase of growth the release of proteins and phenolic acids from cells was observed. Twenty six fatty acids were detected. The most prominent fatty acids found in bacterial cells were 15:0 a, 15:0 i, 17:0 a and 17:0 i. Depending of a phase of bacterial growth, their contents varied from 86.5 to 88.9% of total fatty acids. The remaining fatty acids identified, including regular saturated and monounsaturated as well as iso- and anteiso-branched, 2- and 3-hydroxylated, cyclopropane and odd-numbered derivatives, were present in minor amounts. We have demonstrated that the fatty acid composition of this bacterium changes greatly in different growth phases. These structural changes represent re-arrangement of membranes, which keeps the bacterial cell fit during growth and counteracts the effects of the changing environment.
The enzymatic systems of some microbes can decompose macromolecular organic compounds into simple substances harmless to the natural environment. Some microorganisms used in biodegradation processes obtain their effective capacity after pre-adaptation. This paper compares the biological activity of Bacillus subtilis and Aerobacter areogenes museum bacteria strains to the activity of autochthonous microflora isolated from waste products of a fat preparation plant. As hypothesized, the experimental values show that the activity of autochthonous microflora was significantly greater than the activity of the museum bacteria strains.
The tested strain of Bacillus subtilis DSM 347 was employed in investigations determining the impact of temperature and saccharose concentrations on the in vivo yield of levan synthesis. The best results were obtained in the treatment at 15% saccharose supplementation at 37°C. The obtained levan was subjected to acid and enzymatic hydrolysis and the composition of hydrolysates was examined using the spectrophotometric and densitometric methods on TLC plates.
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