Study on solid state fermentation process of Bacillus subtilis

The influence factors of solid state fermentation process of Bacillus subtilis including carbon,nitrogen,water content,initial pH,inoculum age and inoculum size were studied in the article.The results obtained by using mono-factor experiments and orthodox experiments showed that the optimal solid state fermentation medium was composed of bran 19.5 g,rice crust 0.5 g,soybean 1 g,water 22 mL,and the optimized fermentation conditions were initial pH 7.0,inoculum age of 20 h,0.9 mL inoculum size.Under the above solid state fermentation process,the viable bacteria counts of Bacillus subtilis could reach 43.5 billion/gram.