The wastewater from soybean processing(yellow serofluid)was used to optimize the fermentation medium condition of antagonistic bacterium Pb-4 against fusarium wilt. The single factor experiments were conducted to screen the carbon source of Pb-4 strain in yellow serofluid medium. Orthogonal experiments L18(35)were designed to select the optimal carbon source and inorganic components for Pb-4 strain in yellow serofluid medium,and determine the optimal fermentation medium formulation. The fermentation temperature,pH and inoculation amount of Pb-4 strain were optimized by response surface method(RSM). As results,the composition of the optimal medium was yellow serofluid 1000 mL,corn flour as the optimal carbon source 30 g,(NH4)2SO42 g,MgSO41.5 g,CaCO31.5 g and FeSO40.3 g. The fermentation conditions after optimization were as :temperature 36.3℃,inoculum size 5%,pH 7.4 and incubation time 40 h. Under the optimized conditions,the number of fermented bacteria was up to 42.8×108 CFU/mL,and the maximum biomass OD660 was 0.393,which was in accord with the predicted value 0.390. In conclusion,the optimized medium can be as an effective substitute for traditional medium like peptone,yeast powder,glucose,etc.,moreover as it is simple,cost-efficient and environmentally friendly,thus it can be used as raw material for the scale production of microbial agents.%利用豆制品生产过程中的废水(黄浆水)对枯萎病拮抗菌Pb-4菌株的发酵培养基及其发酵条件进行优化.通过单因素试验筛选Pb-4菌株黄浆水培养基中的碳源;设置因素水平为L18(35)正交试验,对Pb-4菌株黄浆水培养基中最佳碳源和无机盐成分进行筛选和优化,确定发酵培养基配方;通过响应面优化试验对Pb-4菌株的发酵温度、pH和接种量进行优化.结果显示,通过筛选确定玉米粉为黄浆水培养基的最佳碳源;优化后的发酵培养基配方为:1000 mL黄浆水中添加玉米粉30 g、(NH4)2SO42 g、MgSO41.5 g、CaCO31.5 g和FeSO40.3 g;优化后的发酵条件为:温度36.3℃、pH7.4、接种量5%、摇瓶培养40 h.在此优化条件下,发酵菌数可达42.8×108 CFU/mL、最大生物量OD660值为0.393,与预测理论最大值0.3902相吻合.优化后的发酵培养基能够替代蛋白胨、酵母粉和葡萄糖等常规培养基,具有简单、廉价和环保等特点,可作为微生物菌剂规模化生产的原料.
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