Growth pattern and structural nature of amylases produced by some Bacillus species in starchy substrates

Abstract

The growth pattern and microbial biomass formed during metabolic activities of the Bacillus species on starchy substrates was determined. The result showed that the strains B. subtilis (WBS), B. licheniformis (WBL) and B. coagulans (MBC) generally had high growth rate. B. circulans (SBC) and B. coagulans (WBC) has specific affinity for growth and some enzymatic activity on corn starch medium compared with other lower growth observed in B. polymyxa (WBP) but higher enzyme production. The amylolytic Bacillus species obtained utilized white corn starch substrate as a sole carbon source as well as soluble starch. The amylase production values range from 0.022 x 10² unit/cfu in B. circulans (WBC) to 0.912 x 10² unit/cfu in B. licheniformis (WBL) for corn starch, and 0.01 x 10² unit/cfu in both B. megaterium (SBG) and B. licheniformis (SBL) to 0.693 x 10² unit/cfu in B. subtilis (WBS) for soluble starch.

Keywords: Activity, Bacillus, enzymatic, metabolic, starchy, substrate