Background and Aim: Cold active enzymes are used in the leather industry, waste water analysis, detergents, food etc. The aim of this study was to optimize cold-active amylase of the cold tolerant Gram negative bacterium namely BTR209 strain obtained from Binaloud Mountains. Methods: Early verification of amylase activity was investigated with growth of BTR209 strain on the mineral salt agar medium containing 1% starch and adding lugol. Development of a halo zone after addition of lugol solution around the bacterial colony revealed starch decomposition. The quantitative measurement of amylatic activity was conducted using Brenfeld method. In order to examine the effect of incubation, the growth of strains and their enzymatic activity was measured at 20°C after 24, 48, 72, 96, and 120 h. Effect of temperature was examined at various temperatures 15, 20, 25, 30, 37°C. The influence of pH on enzyme production was measured at pH=5, 5.5, 6, 6.5, 7, 7.5, 8, 8.5, and 9. Results: The results indicated that the highest level of enzyme production in this strain occurs after 72 hours and at the logarithmic growth phase (24.15 U/ml). The highest growth and enzyme production in this strain was observed at 20°C (30.02 U/ml) and pH 7.5-8 (72.03 U/ml). Conclusion: The current study suggests that psychrotolerant local bacteria are capable of producing extracellular hydrolytic enzymes that have a good potential to apply in biotechnological industries.

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