Halotolerant Protease-Producing Bacillus Strains Isolated from Fermented Fish Products

Abstract

　In this study, Bacillus strains were isolated from fermented fish product and these strains were characterized for clarification of the effect of Bacillus strains on fish fermentation. Five fish pastes produced in Indonesia and six fish sauces produced in Vietnam were used in this study. Halotolerant protease productive Bacillus strains were isolated from the above mentioned fermented fish products. The strains existed in all samples and most of these grew in a high salt concentration (25% w/v) and produced protease. In addition, they also grew in low concentration (1%). Therefore, the isolated strains were halotolerant bacteria. Phylogenic analysis based on 16 S rDNA sequences indicated that most isolated strains belonged to Virgibacillus halodenitrificans. The results of this study show that not only fish tract protease but also V. halodenitirificans and related species participate in fish fermentation.