产银杏内酯内生真菌的筛选及培养条件研究

Screening of Ginkgolides-producing Endophytic Fungi and Optimal Study on Culture Condition

通过对内生真菌的发酵提取物进行TLC和HPLC-UV分析,进行菌株筛选;对该菌株在不同培养基上的生长情况、产孢量、银杏内酯类物质产量的测定,确定最佳培养基;并用HPLC-ELSD测定了不同时间段的发酵液中银杏内酯类物质含量。结果,筛选出一株产量较高的烟曲霉原变种(Aspergillus fumigatusvar.fumigatus)FG052;对其培养条件的研究表明,PDA培养基、查氏培养基分别为其最佳传代和发酵培养基,菌丝最大生物量在发酵168 h,产银杏内酯类物质高峰在发酵144 h,此时总内酯产量可达0.13 mg/mL,pH值为4.86。本实验筛选的菌株稳定性较好,筛选的培养基价格低廉,碳氮比明确,且总内酯的产量高,可作为规模生产银杏内酯类物质的培养基。

Strain was screened by analyse of TLC and HPLC-UV in the fermentation liquid of endophytic fungi ; the optimum culture medium was chosen by the determination of growth, spores-producing and yield of ginkgolids on different culture medium, and using HPLC-ELSD determined yield of ginkgolids in the fermentation liquid in different time segment. A high yield strain, Aspergillus fumigatus var. fumigatus FG 052, was screened. The results of experimenting on culture conditions of FG 052 strain showed that PDA is the optimum heredity culture medium and Czapek is the optimum ferment culture medium,the maximum amount of mycelia appeared at fermenting for 168 h, the maximum ginkgolides productivity appeared at 144 h and yield reached 0.13 mg/mL,pH is 4.86 here. The strain screened by this study had good stability, the culture medium chosen was low-cost and definite ratio of carbon and nitrogen sources with high yield of ginkgolides which can be chosen culture medium for ginkgolides in large scale.