嗜线虫致病杆菌产生抗生素的培养基及条件

EFFECT OF FERMENTATION CONDITIONS ON ANTIBIOTIC PRODUCTION OF XENORHABDUS NEMATOPHILUS

本文对嗜线虫致病杆菌 (Xenorhabdus nematophilus)产生抗生素的发酵培养基和发酵条件进行了研究 ,同时对该菌代谢过程 p H值、还原糖、总糖、氨基氮与抗生素产量的关系进行了分析。通过筛选该菌对碳源和氮源的要求 ,用正交试验初步确定了该菌产素的最佳发酵培养基和条件为 :玉米粉 1% ,大豆粉 3% ,蔗糖 1% ,蛋白胨 1.5% ,KH2 PO4 0 .0 2 % ,Mg SO4 0 .2 % ,活化剂 T0 .1% ;发酵培养基的起始 p H值在 6 .0～ 8.0 ,种龄 16 h,接种量 4 % ,50 0 m L摇瓶装量 15～ 150 m L的条件下培养 72 h可获得较高的抗生素产量 ;产素量与菌代谢过程中 p H、还原糖、总糖和氨基氮的变化有一定关系 ,通过培养基和培养条件的研究使该菌的产抗生素能力提高了 56 .3%。

The optimum medium and fermentation conditions of the Xenorhabdus nematophilus from Steinernema carpocapsae BJ strain were studied. The relationship between antibiotic activity and pH, reducing sugar, total sugar, amino nitrogen in process of fermentation was analyzed. The optimal medium contained trypton1.5%, corn powder1%, soybean flour 3%, sucrose1%, KH 2PO 4 0.02%,MgSO 4 0.2% and activator 0.1%, Stock cultured for 16h, inoculum size at 4%(V/V)and primary pH of medium ranged from 6.0 to 8.0, fermentation for 72h were of benefit to the yield of antibiotic. The pH, reducing sugar,total sugar and amino nitrogen in process of fermentation were related to the antibiotic activity. The yield of antibiotic increased by 56.3% comparison with nutrient broth.