Technical Session 1:

Title:        Production optimization of thermostable α- amylase by Bacillus subtilis BK1 isolated from Rajgir hot spring, Bihar, India
Authors:   Abha Singh, Shilpi Kiran, Sushma Kumari, Chander Prabha, Sonali Kumari
Abstract:  Large scale industrialization has resulted into significant increase in enzyme demand for various industrial sectors. α- amylases are widely used in industries, but thermostable and thermoactive ones from microbial sources are desirable to economize industrial processes, thus creating greater stress on investigators to explore for newer and cheaper sources. The present study concentrates on optimization of fermentation conditions for en bulk production of α-amylase from bacterial isolate BK1 screened from Rajgir hot spring, Bihar, India. On the basis of phenotypic and genotypic characterization, isolate BK1 was identified as Bacillus subtilis BK1. Submerged fermentation technique was followed to investigate the effect of different production parameter like incubation period, pH, temperature, starch concentration and nitrogen sources. Maximum enzyme (21.8 U/ml) was produced after 48 h of incubation with initial pH 7.0 at 50±2ºC. Enzyme production was highest under optimized production conditions, i.e., 40ºC, 7.0 pH, 2.0% starch and 0.6% tryptone as nitrogen source. Crude α-amylase was characterized with optimum pH of 7.5. Its optimum temperature was 70°C, still the activity was maintained at 100°C. The enzyme was stable and retained 89%, 72% and 51% of its original activity at 60°C, 70°C, and 80°C, respectively after 60 min of pre-heating. The results were encouraging in terms of enzyme productivity and thermos ability, indicating its immense potential for wide commercial applications.

Keywords: Thermostable, α-amylases, Bacillus subtilis BK1, Rajgir hot spring, Submerged fermentation (SmF)
Pages:       041-047

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