Optimization of high- density fermentation conditions for Lactobacillus plantarum by response surface methodology

In this study,response surface methodology was applied to optimize high density fermentation parameters for Lactobacillus plantarum KLDS 1.0391.Central composite design was used to optimize fermentation temperature,fermentation p H and inoculation following the single factor tests. Corn steep powder was used as fermentation medium and the total number of viable bacteria was used as the main indicator. The results showed that the influence of three factors on the number of viable bacteria in the fermentation broth was in order as follows: fermentation temperature > inoculation > fermentation p H. The number of viable bacteria achieved9.58 lg CFU / m L under the optimum fermentation parameter which included fermentation temperature of 34.7 ℃,fermentation p H of 6.2,inoculation of 3.1% and fermentation time of 11 h.There's no significant difference between the results obtained according to optimum conditions and the predicted value,and the relative error was 1.33%between them.The established model can effectively reflect the actual fermentation conditions.