高山被孢霉挥发性次生代谢产物分析

Analysis on the Volatile Secondary Metabolites of Mortierella alpina

[目的]研究花生四烯酸生产菌高山被孢霉挥发性次生代谢产物成分,并探讨其代谢途径的变化。[方法]采用固相微萃取提取高山被孢霉对数生长后期发酵液上方空气并进行GC-MS分析。[结果]一共分析得到13种化合物,其中,12种均为C15H24的倍半萜化合物,浓度占总组分的99.62%。含量最高的3个化倍半萜合物Thujopsene-(12)(斧柏烯)、α-Guaiene(愈创木烯)和Aristolene(土青木香烯)分别占到总含量的10.66%、33.69%和34.85%。通过次级代谢产物的检测能够较充分证明高山被孢霉中存在倍半萜的代谢途径。[结论]原始菌株经过诱变致使异戊二烯或倍半萜分支途径中一个或几个关键酶的基因发生突变而使其编码的酶活性增强,从而导致此条代谢途径的通量增加而有利于倍半萜化合物的大量积累。

[ Objective] The study, was to investigate the volatile components of secondary metabolites from M. alpine producing arachidonic acid and explore the changes in its metabolic pathway. [ Method] The air above M. alpine broth was extracted by solid-phase microextraction （SPME） during the post-exponential phase of growth and analyzed by GC-MS. [ Resuh] 13 compounds were identified, 12 of which were sesquiterpenes with C15H24 formula and accounting for 99.62% of the complete compounds. Tbujopsene-（12）, α-Guaiene and Aristolene were three most sesquiterpenes accounting for 10.66% , 33.69% and 34.85% of total content,respectively. It can be sufficiently certified that sesqniterpene metabolic pathway existing in M. alpine. [ Conclusion] One or several key enzymes genes mutation enchaned the activities of their encoding enzymes in isoprene or sesquiterpene pathuay after initial strain mutation,which led flux rising of this metabolic pathway and helped mass aceamulation of sesquiterpenes.