A new strategy to applyBacillus subtilisMA139 for the production of solid-state fermentation feed

AIM: The study investigated the potential of using Bacillus subtilis MA139 in combination with Lactobacillus fermentum and Saccharomyces cerevisae to produce solid-state fermentation feed. METHODS AND RESULTS: In a pure fermentation, B. subtilis MA139 was able to grow and synthesize antimicrobial substances at temperatures from 25 to 37 degrees C and at a pH from 5.0 to 9.0. Subsequently, B. subtilis MA139, Lact. fermentum and S. cerevisae were used as starter strains co-inoculated in unsterilized substrate (feed-grade soybean meal and wheat bran). Following 10 days of fermentation in a newly developed plastic bag equipped with a one-way valve, lactic acid bacteria and Bacillus became the predominant strains while S. cerevisae cells decreased slightly. Enterobacteriaceae (Escherichia coli K88 and Salmonella typhimurium) were not detected. CONCLUSIONS: Use of B. subtilis MA139 as a starter strain co-inoculated with S. cerevisae and Lact. fermentum successfully controlled the growth of enterobacteriaceae. SIGNIFICANCE AND IMPACT OF THE STUDY: This study provided a facile and low-cost way to produce solid-state fermentation feed.