小分子肽产生菌培养基碳源与氮源的优化

Optimization of carbon sources and nitrogen sources in ferment culture medium of bacterium producing small molecular antibacterial peptides

目的:探讨不同碳源、氮源对乳酸杆菌小分子肽产量及抑菌效果的影响。方法:用1%的不同碳源和2%的不同氮源替换基础培养基中的葡萄糖、酵母膏和蛋白胨,同时改变基础培养基中的葡萄糖浓度,分别在相同条件下发酵,双层平板法检测抑菌效果,同时测定发酵液的OD值和PH值。结果:不同碳源均能促进LB-9菌株的生物量增加,生物量从高到低依次为葡萄糖、果糖、蔗糖、乳糖、木糖、糊精、玉米浆、可溶性淀粉,其中葡萄糖为碳源的发酵液的生物量最大。各有机氮源均可促进小分子肽的产生,而无机氮源不能。有机氮源发酵液的抑菌效果从高到低依次为酵母膏、牛肉膏、多胨、鱼蛋白胨、胰蛋白胨、大豆胨。结论:葡萄糖是本实验最好的碳源。葡萄糖为碳源的发酵液的生物量最大,小分子肽产量随葡萄糖浓度的增加而增加。菌体细胞生长最好的氮源是酵母膏,有机氮源均可促进小分子肽的产生,而无机氮源不能。

Objective：To investigate the effect of different carbon and nitrogen sources for inhibition activity of small molecular antibacterial peptides producing by lactobacillus in ferment culture medium.Methods：To substitute glucose,yeast cream and peptone of seed culture medium using different 1% carbon sources and 2% nitrogen sources respectively.PH,OD and inhibition activity of culture medium were tested.Results：The different carbon sources can improve the amount of antibacterial substance producing by strain LB-9,and the glucose was the best carbon sources in fructose,sucrose,lactose,xylose,dextrine,corn steep liquor and soluble starch.Organic nitrogen sources including yeast cream,beef extract,tryptone,soyapeptone and so on were better than inorganic nitrogen sources about inhibition activity.Conclusion：The result confirmed that glucose was the best carbon source and antibacterial substance increased with glucose consistency increasing.Bacterial cells in yeast cream grew best among the nitrogen source.Organic nitrogen sources can stimulate lactobacillus producing small molecular antibacterial peptides while inorganic nitrogen sources can＇t.