Process Optimization of Bacillus subtilis fermented Rose laevigata michx

The aim of this experiment was to study the optimum process of Rose laevigata michx fermented by Bacillus subtilis. The process of Bacillus subtilis fermented Rose laevigata michx was optimized by test method combining single factor and response surface.The Rosa laevigata michx polysaccharide content was chosen as indexes and the key factors which had greater impact on ferment effect were selected from carbon source,nitrogen source,water content,inoculation amout and fermentation time for further optimize by response surface. The results showed that water content,inoculation amount and fermentation time were the key factors among the five single factors. When the water content was 53.79%,inoculation amount was 5.74%,fermentation time was 2 days,the average content of Rosa laevigata michx polysaccharide was 15.47% which closed to predicted value (15.36%).Compared with the polysaccharide content in unfermented Rosa laevigata michx,that of fermented Rosa laevigata michx was increased 47.47%. The fermentation process was simple and easy to operate with remarkable fermentation effect,and it could provide theoretical basis for the development of the green feed additive.