摘要

The aim of this work is to enhance enduracidin production by Streptomyces sp. MC079. Based on the time course analysis of the specific cell growth rate and specific enduracidin formation rate, a two-stage pH control strategy was proposed to improve enduracidin production by shifting the culture pH from 5.5 to 5.8 after 112 h of cultivation. By applying this pH control strategy, enduracidin concentration and productivity was 51.2 and 65.0% higher than results with uncontrolled pH batch fermentation. For further enhancement of enduracidin production, the effects of constant-rate feeding and pH-shift feeding strategy were investigated. The results indicated that the pH-shift feeding strategy increased the maximum concentration and productivity of enduracidin to 61.37 mg/L and 0.697 mg/L/h in the constant-rate feeding fermentation process. This is 73.3 and 88.9% higher than results with uncontrolled pH batch fermentation, respectively. The obtained optimal pH shift feeding strategy may be useful for the industrial-scale microbial production of enduracidin.