A Preliminary Study On Isolation, Identification And Active Ingredient Of Endophytic Fungi From Astragalus Membranaceu (Fisch.) Bge. Var. Mongholicus (Bge.) Hsiao

Endophytc lives together with medical plant,some endophytes are enable to affect produetion and accumulation of medical plant active in gredient, but there is no report about endophytes of Astragalus membranaceus plant so far.In this thesis,we studied the isolation,purification and identification of endophytc lived in Astragalus membranaceus, preliminary study the optimal fermentation conditions and active components of astragalusFirst of all,28 strains of endophytic fungi were isolated from the root of the healthy Astragalus membranaceus plants based on a variety of surface disinfection method by four kinds of nutrient medium. Refer to Fungus Idemtofocatopm Manual and Fungi taxonomy, Through training patterns, microscopic observation,18S rDNA of endophytes were sequenced.Found that, these strains can be classified into7Fusrium.sp (19), Bionectria.sp (3), Emericella.sp (2), Clonostachys.sp(1), 1Acremonium. sp (1), 1Penicillium.sp(1) and Aspergillus.sp(1).Shaking culture 5 strains of them under the same formula composition of fermentation, and a comprehensive analysis of the culture temperature,speed of revolution the amount of inoculation,liquid volume and culture period, five factors on dry cell weight,and probe into the interaction between the various factors. The results showed that:the sensitivity of different endophytic fungi on different liquid fermentation factors are slightly different, but the main effected factors of liquid fermentation are the liquid volume,speed of revolution,culture period and culture temperature, the optimal level of the amount of inoculation in this study did not focus on. The data was analyzed by DPS method and showed that the liquid volume 100 ml/250 ml Erlenmeyer flask, culture temperature 31℃and speed of revolution 150r/min, most fungies could reach the maximum dry cell weight after 8 days of incubation.Fermental cultivated to28 strains endophytic fungi, examine the radix astragali flavanone, saponin and polysaccharide by color reaction,TLC and HPLC comparison indicated, but there was no active constituent to be found.