榄仁内生真菌JLR6的鉴定及其发酵条件优化

Identification of an Endophytic Fungi JLR6 form Terminalia catappa and Optimization of its Fermentation Conditions

榄仁是热带及亚热带地区的一种常见药用植物,目前关于榄仁内生真菌的研究较少。从榄仁体内分离出一株内生真菌JLR6,利用对峙生长法测试JLR6对香蕉炭疽菌及芒果炭疽菌的拮抗活性,通过ITS序列分析对其进行初步鉴定,并利用Plackett-Burman设计结合响应面的方法对菌株JLR6的发酵条件进行了优化。结果表明:菌株JLR6对香蕉炭疽菌及芒果炭疽菌有明显的拮抗活性,皿内抑制率分别为45.50%和57.90%,通过ITS序列分析,初步将JLR6鉴定为Diaporthe sp.;优化后菌株JLR6的最适发酵条件为细菌学蛋白胨10 g/L、葡萄糖20 g/L、酵母粉17.82 g/L、装液量87.59 m L、接种量9.06%,于180 r/min、28℃条件下培养7 d,生物量达到4.79 g/L。

Terminalia catappa is a common medicinal plant in tropical and subtropical regions, and there is few study on its endophytic fungi so far. An endophytic fungi JLR6 was isolated from Terminalia catappa, and its antagonistic activity to Colletotrichum musae and Colletotrichum gloeosporioides were determined by confrontation growth method. The strain was identified by ITS sequence analysis, and the fermentation conditions were optimized by Plackett-Burman design and response surface methodology.The results showed strain JLR6 had obvious antagonistic activity to C. musae and C. gloeosporioides, and the inhibition rates were 45.50% and 57.90%, respectively. Strain JLR6 was identified as Diaporthe sp.according to ITS sequence. After optimization, the optimal fermentation conditions were 10 g/L peptone,20 g/L glucose, 17.82 g/L yeast extract, 87.59 m L of loading volume and 9.06% of inoculum size. After 7d culture on 28℃, 180 r/min, the biomass was up to 4.79 g/L.