Showing 3 results for Alkaline Protease
M.s. Borhani , Z. Etemadifar , G. Emtiazi , E. Jorjani ,
Volume 9, Issue 4 (12-2018)
Abstract
Aims: Alkaline protease is one of the most important groups of industrial enzymes with many applications. The aim of this study was to determine the physicochemical parameters affecting the production of alkaline protease enzyme produced by Bacillus pseudofirmus MSB22 by one-factor-at-a-time (OFAT) method and optimize the production of this enzyme by the response surface methodology (RSM) in the form of a rotatable central composite design.
Materials and Methods: In the present experimental study, the isolation of microorganism producing alkaline protease from wastewater from sausage and lunch meat factories in Isfahan was carried out. The morphological and biochemical characteristics of the strain were performed according to the Bergey's book and amplification of 16S rRNA gene sequences. Detection of metalloproteinase gene and alkaline serine protease was done by polymerase chain reaction (PCR) reaction and enzyme activity measurement was performed by Folin reagent. Screening of variables effective in enzyme production was done, using one-factor-at-a-time method and optimization was performed by response surface methodology. MEGA 6 software was used for phylogenetic analyses. To analyze the data, the Design Expert 7 software and the one-way analysis of variance were used.
Findings: The maximum protease production, which was 1.85 times higher than that of OFAT method and 3.45 times higher than unoptimized conditions was obtained, using 1% w/v xylose, 3% w/v beef extract, 4% v/v inoculation size, pH 10, and 30°C. The established quadratic model had a great ability to predict responses to new observations due to a high value of the predicted determination coefficient.
Conclusion: OFAT and RSM strategies are useful screening and optimization methods, respectively and sub I and sub II genes (alkaline serine protease genes) are detected in Bacillus pseudofirmus MSB22.
M. Nasre Taheri , Gh.h. Ebrahimipour , H. Sadeghi ,
Volume 10, Issue 1 (3-2019)
Abstract
The Stability of protease in organic solvent media has been widely discussed for more than two decades. Proteases can catalyze synthetic reactions in organic media, by this way solvent stabilities of proteases are very important. In this study, we reported a bacterium isolated from hot spring of Geinarje, Iran producing an organic solvent stable protease. Protease producing bacteria were screened on skim milk agar and the formation of a clear zone around the bacterial colony was investigated. Proteolytic activity was assayed by a modified caseinolytic method using casein as a substrate. The best alkaline protease producing bacterium was selected and identified on the basis of 16S rDNA gene sequencing and morphological and biochemical characteristics. The effect of organic solvents, temperature, pH, and NaCl on proteolytic activity were examined. According to phylogenetic analysis, morphological and physiological tests, isolated, the bacterium was identified as a new strain of Brevibacillus borstelensis. This strain was able to produce an extracellular organic solvent-stable protease with 0.53U/ml enzyme activity. After 2 hour incubation at 30°C the protease of Brevibacillus borstelensis AMN was active in wide ranges of organic solvents, and its activity was enhanced in the presence of 25% (V/V) isopropanol. The biochemical properties of the enzyme revealed that the optimal pH and temperature for protease activity were 9.0 and 60°C, respectively. Our finding indicated that these robust properties of protease, like outstanding activity and stability in organic solvents and alkaline medium, might be applicable for various industrial biotechnologies.
Volume 20, Issue 145 (2-2024)
Abstract
This study was carried out with the aim of covalent immobilization of Aspergillus oryzae beta-galactosidase and Bacillus licheniformis protease on multi-walled amino-carbon nanotubes. In this method, fractional 2k design was used to study the effect of seven continuous factors (activation pH, glutaraldehyde molarity, activation time, buffer solution pH, buffer solution molarity, MWCNT-NH3-glutaraldehyde amount and stabilization time) on the stabilization efficiency and enzyme activity. . Design-expert software was used to analyze data and draw graphs. The results showed that the aforementioned factors predict the level of enzyme activity of Bacillus licheniformis protease and Aspergillus oryzae beta-galactosidase with correlation coefficients of 0.80 and 0.92 at the rate of 77 and 88%, respectively. Also, the correlation coefficient of the covalent fixation efficiency model of Aspergillus oryzae beta-galactosidase and Bacillus licheniformis protease on multi-walled carbon nanotubes was 0.89 and 0.82, respectively, and the studied factors were able to determine the covalent fixation beta efficiency, respectively. Aspergillus oryzae galactosidase and Bacillus licheniformis protease on multi-walled amino-carbon nanotubes predict 83 and 77%, respectively.
