Abstract

Bacillus strains isolated from different habitats were screened and identified for high protease activity. Two of the bacillus strains genetically identified as Bacillus subtilis AG-1 and Bacillus subtilis EAG-2 exhibited tremendous potential for protease production. The strains were optimized with respect to production media and its components. Culture conditions were critically investigated with reference to other key determinants, involving inoculum concentration, incubation time, initial pH of the medium and temperature. The optimum production pH and temperature was found to be 7.0 and 35^oC for B. subtilis AG-1, while 7.2 and 37^oC were the optimum conditions for B. subtilis EAG-2. The inoculation ratio and incubation time were determined for both of the strains as 1% (v/v) and 24-32 h respectively. The study reveals that, high protease yield can be achieved over a moderate fermentation period with relatively economical production costs. Hence these strains might be useful for commercial exploitation.

Key words: Bacillus subtilis, protease, production medium, pharmamedia, optimum growth.