Thermal stability of partially purified α-amylase produced by <em>Brevibacillus borstelensis</em> R1 from the coastal waters of Bay of Bengal, Visakhapatnam

Abstract

Highest α-amylase activity of <em>Brevibacillus borstelensis</em> R1 was observed at 37⁰C (6133±58U/ml). The α-amylase retained its activity after 10hrs exposure to 4⁰C with negligible variations in its activity. Alpha-amylase have several applications in starch processing, desizing of textiles, paper sizing, detergent additive, bread improvement, ethanol production, sewage treatment, effluent treatment and other fermentation processes. Highest α-amylase activity was observed at 37⁰C (6133±58U/ml), while the lowest at 70⁰C (2360±40U/ml). Only 38.47% activity remained at 70⁰C. Optimum temperature of partially purified enzyme was similar to the crude enzyme. Partially purified enzyme was tested for its stability (1-10hours) at temperatures ranging from 4⁰C to 70⁰C. At 20⁰C it retained 34.2% activity, at 25⁰C 44.1%, at 37⁰C 34.7%, at 50⁰C 56.2%, at 60⁰C 38.2% and at 70⁰C it retained 30.8% activity upon exposure for about 10 hrs.