【摘要】 目的:研究放线菌株F菌的培养条件,优化其发酵条件,分析其抗菌物质的稳定性。方法:以平板对峙法检测抑菌活性,通过比较抑菌圈直径和抑菌率,优化培养条件。结果:F菌株对黄瓜枯萎病和番茄灰霉病均有一定的抑制作用。菌株F的最佳接种量为10mL/100mL,最佳碳源为葡萄糖,最佳氮源为硝酸钾。最适发酵条件为:葡萄糖20g,硝酸钾15g,酵母膏5g,蛋白胨2g,CaCO34g,NaCl4g,蒸馏水1000mL,pH7.2～7.4。F菌株抗菌物质在80℃时仍保持很好的抑菌活性,但温度继续升高时活性下降。不同pH间抑菌率存在差异,pH值为6时抑菌率出现最大值60.46%,pH值为9时抑菌率最小,为57.93%。在发酵培养液培养以pH6为宜。结论:F菌株无菌发酵液具有较好的温度、光照和酸碱性的稳定性。更多还原

【Abstract】 Objective:The medium compositions and ferment condition were optimized, and antimicrobial substances stability were discussed in this paper.Method:Though inhibition zone and inhibition rate compare, cultural conditions were optimized with flat culture method.Result:The results indicated that F strain has certain inhibitory action to Fusarium oxysporium and Botrytis cintrea fungi. The best inoculation amount to strain F was 10mL/100mL. The best carbon source was the glucose, and the feasible nitrogen source was the KNO3. The most suitable fermentation condition was glucose 20g, KNO3 15g, yeast extract 5g, peptone 2g, CaCO3 4g, NaCl 4g, distilled water 1000 mL, pH 7.2～7.4.Conclusion:Sterile metabolite of F strain maintains a good stability to temperature, light and pH.更多还原