Isolation, Identification and Optimization of Culture Conditions of Bacillus sp. Strain PM1 for Alkalo-thermostable Amylase Production

Aims: To isolate and optimize the culture conditions for thermo stable and alkaline amylase production from bacteria.
Study Design: Optimization of different physiological and nutritional parameters for amylase production and kinetic studies of amylase.
Place and Duration of Study: Soil Samples: Herbal garden of Amity University Haryana, Gurgaon (Manesar), India, between April 2012 and September 2012.
Methodology: Amylolytic isolates were selected by flooding the nutrient agar plates containing 2% starch with Lugol solution. Isolates were selected on the basis of higher ratio of clear zone to colony size and grown in nutrient broth containing 2% starch. The level of amylase was detected in the culture filtrate. The selected isolate showing maximum amylase production was identified on the basis of 16S rDNA amplification.
Results: An Alkalo-thermostable amylase producing bacterial isolate from soil was identified as Bacillus sp. strain PM1 on the basis of 16S rRNA. It yielded 3.5 U/ml of amylase in medium containing (%) starch 2.0, beef extract 0.5, NaCl 0.5 at 50ºC, pH 7.0 at 180 rpm after 72 h. The optimum pH and temperature for amylase activity was 8.0 and 50°C, respectively. The enzyme exhibited 67% activity after 60 minute incubation at 50ºC. At pH 8.0, the enzyme retained 78% activity after 4 h.
Conclusion: The properties of the isolated enzyme are adequate for its use in starch processing and baking industry.