响应面法优化具有抑菌作用的链霉菌D-8菌株的发酵工艺研究

Optimization of fermentation conditions bacteriostasis of Streptomyces sp. D-8 by response surface method

目的采用响应面法(RSM)优化链霉菌D-8菌株产抑菌物质的发酵条件。方法采用单因素试验确定由章鱼肠道获得的链霉菌D-8菌株产抑菌物质的最佳碳源与用量、Na Cl浓度及培养时间。以金黄色葡萄球菌为指示菌,双层平板透明圈法测定发酵液的抑菌活性,采用响应面Box-benhnken试验设计,对链霉菌D-8菌株产抑菌物质的工艺条件进行优化。结果建立了该菌株抑菌性随可溶性淀粉含量、Na Cl浓度及培养时间变化的多项二次回归方程,得出该菌株产抑菌物质的最佳工艺条件是可溶性淀粉2.44%,氯化钠浓度3.50%,培养时间为100h,在此条件下,透明圈直径达到2.51cm,比优化前提高了2.21倍,与预测值(2.42cm)较为接近。结论实验结果表明预测模型可靠,用该模型对链霉菌D-8菌株的抑菌活性进行预测是可行的。

Objective To optimize the fermentation conditions ofStreptomyces sp. D-8 by the response surface method （RSM）. Methods The optimum carbonium, sodium chloride and culture time of Streptomyces sp. D-8 strain were determined by single factor experiment. Simultaneously, production condition of antibacterial activity by the strain was optimized by Box-benhnken experiment. Results The quadratic regression equation for antibacterial activity of the strain with carbonium, sodium chloride and culture time was established. The results showed that the optimal condition was amylogen 2.44%, sodium chloride 3.50%, culture time 100h. Under optimization conditions, the inhibition zone diameter reached 2.5 lcm, improved 2.21 times, and closed to forecast（2.42cm）. Conculsion This study proves that the prediction model is feasible and reliable, and can be applied to optimization of antibacterial activity fermentation conditions.