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Alpha-amylases are the most important amylases used in industry. Among them, thermophilic alpha-amylases are of particular importance, which is due to their activity and stability in high temperatures. These enzymes produced by thermophile micro-organisms including bacteria. These thermophilic alpha-amylases are used in various industries such as processing of starch as well as production of detergents and biofuels. In this research, the bacteria which produce the thermophilic alpha-amylases were isolated and characterized in hot springs of Gorooh village in Kerman province. According to the results of screening on the specific liquid and solid media, AT59 was selected as the best strain. Morphological and biochemical characterization of the isolated strain indicated that it belonged to Bacillus sp. and was gram-positive, catalase positive, casein hydrolyzing and acid producing from lactose and sucrose. The results obtained from the optimization of the enzyme production medium showed that among the carbon, nitrogen and ion sources investigated, starch (1 gr/l), gelatin (2 g/l) and magnesium sulfate (1 g/l) had the most increasing effect on the production of AT59 alpha-amylase. Moreover, the highest enzyme production was obtained at pH 5. This enzyme also demonstrated the highest degree of activity and stability in 80 and 70 ℃, respectively. These findings suggested that this enzyme has a considerable potential for use in starch industry.
 

 
 

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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 ^oC. Phytase stability was at its optimum in a pH range of 5.0–8.0. Phytase activity increased in the presence of CaCl₂, ZnCl₂, and MnSO₄ 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.