地衣芽孢杆菌W10发酵产生抗菌蛋白的研究

Fermentation Process of Antifungal Protein Produced by Bacillus licheniformis W10

地衣芽孢杆菌Bacillus licheniformis W10是1株生防细菌,其能产生抗菌蛋白,对多种植物病原菌有较好的抑制效果。本试验研究了菌株W10产生抗菌蛋白的发酵条件,为工厂化生产工艺提供技术支持。试验结果表明,接种菌龄12 h,2%接种量,发酵液pH 7.0,发酵培养60 h是菌株W10产生抗菌蛋白的适宜发酵条件。控制发酵温度有利于抗菌蛋白积累,第一段温度为30℃培养20 h,第二段温度为28℃至发酵结束。最佳溶氧量为20%。2次补料发酵效果要高于分批发酵,补料为500 mL含10 g·L 1葡萄糖和5g·L 1蛋白胨的培养基;选用200 mg·L 1聚氧丙烯聚氧乙烯甘油醚(GPE消泡剂,泡敌)为消泡剂。利用优化的控制条件发酵培养菌株W10,与优化前相比,对目标病菌的抑菌率增加了34.6%。

Bacillus licheniformis W10 is an antagonistic bacterium, which can produce antifungal protein inhibiting growth to a variety of plant pathogenic fungi. The technical conditions of fermentation W 10 to produce antifungal protein were studied. The results indicated that yield of antifungal protein was promising under the conditions of inoculation bacteria for 12 h, 2% inoculum volume, fermentation for 60 h and pH 7.0. During the fermentation, changing culture temperature was favorable to the antifungal protein accumulation and increased its inhibitory effect against plant pathogen Botrytis cinerea, with fermentation temperature of first stage was 30 ~C for 20 h, and then was adjusted to 28 ~C until the end of fermentation. The suitable dissolved oxygen value was 20%. The better fermentation method was two fed-batch culture with 10 g.L-1 glucose and 5 g.L-1 peptone as the supplement medium. The defoaming substance was defoamer GPE （polyoxypropylene-polyoxyethylene glycerol ether） with 200 mg.L-1. Under the optimized fermentation conditions, the inhibitory effect of the strain W 10 against B. cinerea reached 99.5%, increasing 34.6% compared with the control.