Thermostable α-amylase production by an extreme thermophile Bacillus thermooleovorans

S. NARANG AND T. SATYANARAYANA. 2001. Aims:α‐Amylase production by a newly isolated thermophile, Bacillus thermooleovorans, was studied under different cultivation conditions. Methods and Results: The influence of various carbon and nitrogen sources on α‐amylase production was quantified in batch fermentation in shake flasks. Starch and tryptone were observed to be the ideal carbon and nitrogen sources, respectively. Cultivation of the organism in a chemically defined medium consisting of glucose, riboflavin, cysteine, MgSO4, K2HPO4 and NaCl led to a near twofold increase in the production of α‐amylase in comparison with that in the complex medium. The increase in enzyme production was achieved using vitamins and amino acids. When the organism was grown in a laboratory fermenter in the optimized complex medium, the noticeable effects were the near abolition of the lag phase, a 2·2‐fold increase in enzyme production and a reduction in optimal production time from 12 to 4–5 h. Conclusions: Enhancement of amylase production was achieved under various cultivation conditions. Significance and Impact of the Study: Bacillus thermooleovorans produces a calcium‐independent and thermostable amylase which can find use in starch saccharification.