Production and biochemical characterization of a thermostable phytase from Bacillus amyloliquefaciens LOR10

. Phytase can improve the nutritional value of plant-based foods by enhancing protein digestibility and mineral availability through phytate digestion in the stomach and the food processing industry. Microbial sources are more promising for the production of phytases on a commercial scale. The objectives of this exploration were to screening and isolation of phytase-producing bacteria from hot spring with commercial interest. Molecular identification of the best isolate was achieved by the 16S rDNA gene. Optimization of phytase production was prepared in the presence of different phosphate, nitrogen, and carbon sources. Enzyme activity and stability were also explored in the presence of different pHs, temperatures, and ion compounds. Comparing the 16S rDNA gene sequence of the isolate LOR10 with those in GenBank using Clustal omega shows 98% sequence homology with Bacillus amyloliquefaciens. Medium optimization studies showed that galactose, yeast extract, and tricalcium phosphate were the best sources of carbon, nitrogen, and phosphate for phytase production, respectively. The optimum temperature activity was also observed to be 70 o C. Phytase stability was at its optimum in a pH range of 5.0–8.0. Phytase activity increased in the presence of CaCl 2 , ZnCl 2 , and MnSO 4 about 1.4, 2.3 and 1.6 folds, respectively. It could be mentioned that phytase activity decreased by about 30 % in the presence of EDTA and SDS. On the basis of the results, it could be concluded that LOR10 phytase has a great potential for commercial interest as an additive to animal plant-based foods.