Production of protease by Bacillus subtilis grown on sardinelle heads and viscera flour

Fish flours from Sardinelle (Sardinella aurita) were prepared and tested fo r protease production by Bacillus subtilis. Protease synthesis was strongly induced when cells were grown in media containing only a combined head and viscera preparation. Sardinelle heads and viscera flour enhanced protease production up to 100% more than commercial peptones. The enhancement could have been due to a high lipid content, which might have contained nutrition al factors acting as inducers, since defatting fish meal led to a decrease in protease production. (C) 2001 Elsevier Science Ltd. All rights reserved.