Introduction and Objectives:Cold-tolerant bacteria often produce enzymes with optimum activity at moderate to low temperatures Amylases constitute one of the most important groups of industrial enzymes. Amylases have numerous biotechnological applications such as food processing, pharmaceutical and detergent industry. The objective of present study is isolation and characterization ofpsychrophilic and psychrotolerant bacteria producing amylase. Materials and Methods: soil samples were collected from Binalood Mountains. Serial dilution were plated on TSA medium and incubated at 4, 8 and 20 °C. Distinct colony types were purified by streaking method. The amylase activity was assayed on TSA medium supplemented with 1% (w/v) soluble starch. Amylase production was determined by the development of a colorless halo zone surrounding bacterial colonies when Lugol solution was added to the plates. To determine the amylase activity, the reaction mixture containing 0.25 ml diluted enzyme solution plus 0.25 ml 1% (w/v) starch was dissolved in 0.05 M buffer phosphate (pH 7.8), incubated at 30 °C for 15 min.The amount of liberated reducing sugar was determined by the dinitrosalicylic (DNS) acid method and its absorbance was recorded at 540 nm. Results: A total of 240 aerobic heterotrophic bacterial strains were isolated from Binalood Mountains. 123 and 21 from these bacterial strains isolated were psychrotolerant and psychroplilic, respectively. 50% from these strains showed the amylase activity. Conclusions: Identification and Characterization of these strains isolates using molecular methods is being carried out. Further studies will be necessary to improve of amylase production conditions in culture media.

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