Nutritional requirements and cultural characteristics of Bacillus apiarius CBML-152 for the production of thermostable α-amylase

Abstract

Summary Nutritional requirements and cultural characteristics of Bacillus apiarius CBML-152, producing a thermostable α-amylase, indicated potentialities of the strain for industrial production of α-amylase. The strain showed a “biphasic” nature of growth in complex medium. Under “still- and shake-culture” conditions, maximum enzyme production occurred during the first exponential phase and the first stationary phase, respectively. Optimum incubation periods for α-amylase production in “still- and shake-cultures” were 32–38 hrs and 20–25 hrs, respectively. Mn 2+ , Ca 2+ , Zn 2+ , Mg 2+ , Fe 2+ , Fe 3+ , Na + , and K + ions were important for α-amylase production. (NH 4 ) 2 HPO 4 was best utilized as inorganic nitrogen and phosphate source. Eight amino acids (alanine, arginine, asparagine, cystine, histidine, lysine, phenylalanine, and valine) and four vitamins (biotin, pantothenic acid, pyridoxine, and thiamine) increased the α-amylase production. Glutamine and leucine had some inhibitory effect. Remarkable increase in α-amylase production was obtained when various oil seed cakes and husks of some pulses were used by replacing peptone. The non-edible and poisonous mushrooms were found to be exploitable for α-amylase production as supplements for organic nitrogen and vitamins.