Natamycin production by Streptomyces gilvosporeus based on statistical optimization

Natamycin has been widely used as a natural preservative to prevent mold contamination in food. In this study, statistically based experimental designs were employed for the optimization of medium components for natamycin production by Streptomyces gilvosporeus. After glucose, yeast extract, and soy peptone were screened as suitable carbon and nitrogen sources, a full factorial design was used to evaluate the effects of various factors on natamycin production. Glucose and pH were identified as having significant effects (with confidence level >90%). Glucose concentration and initial pH were subsequently optimized by use of a central composite design. The result indicated that glucose and pH had a significant interactive effect on natamycin production. The optimal glucose concentration and initial pH value were 38.2 g/L and 7.8, respectively. This optimization strategy led to a natamycin yield of 2.45 g/L, which was nearly 90% higher than that in the original medium.