OPTIMIZATION OF ALKALINE PROTEASE PRODUCTION BY STREPTOMYCES AMBOFACIENS IN FREE AND IMMOBILIZED FORM

Abstract

Optimization of alkaline protease production by Streptomyces ambofaciens NRRL 2420 in free and immobilized form was investigated using submerged fermentation technique. The optimum conditions for maximum alkaline protease production 342 unit mL^-1 were 30°C at pH 8.5 and incubation time 96 h in free cell cultures using starch 20 g L^-1 as carbon source and yeast extract 5 g L^-1 as nitrogen source. The incubation time for the best yield of 344 unit mL^-1 was reduced to 72 h under the optimized fermentation conditions by immobilized cells adsorbed on synthetic cotton fibers. Data obtained during 5 reusable cycles showed higher levels of enzyme in shorter time duration. Immobilization of Streptomyces ambofaciens NRRL 2420 on synthetic cotton fiber permit repeated reuse of the cells under the optimized fermentation conditions.