Screening Of Resin Glycoside-producing Endophy Fungi And Optimization Of Fermentation From Ipomoea Pes-caprae

Ipomoea Pes-caprae is a kind of sand-fixation plants and medicinal plant that contains a lot of active material, it was used in environment greening and medicine. Many researches extracted a lot of useful substances from Ipomoea Pes-caprae through chemical method. Resin glucoside is characteristic chemical composition of plants the genus yams, it has new chemical structure and diversity of biological activity. It provided a good basis for synthesis of new compounds and new drug development. this experiment isolates endophytic fungi MJ8 which can produce resin glycoside from Ipomoea Pes-caprae,identify target strain and optimize fermentation conditions to improve the production of resin glucoside.The results are as follows: 1)This experiment isolated 120 strains of endophytic fungi from the stems and leaves of Ipomoea Pes-caprae by using tissue separation,then screened target strain through shaking flask fermentation, after column chromatography and distillation, compared with standard by using thin layer chromatography (TLC).Finally MJ8 was screened,it can produce resin glucoside.2) firstly we preliminary classified MJ8 as a pestalotiopsis fungus by mathematical morphology method which observeed colony, mycelium and conidium morphology, then we analyzed 18 s rDNA sequence and ITS sequence by molecular biology method,we think MJ8 is a new pestalotiopsis fungus according to the phylogenetic tree.3) firstly we determined nitrogen source, carbon source, fermentation time and the best condition of a variety of substances in PDB culture medium by single factor experiments, then the Plackett-Burman test indicated that lactose, ammonium sulfate, temperature and inoculation quantity had significant influence on test results, finally we determined the best fermentation conditions for lactose concentration of 40.200 g/L, the concentration of ammonium sulfate 13.800 g/L, the temperature of 31.8℃, the inoculation amount of 5%, ferrous sulfate concentration of 0.010 g/L, potassium chloride concentration of 2.000 g/L, magnesium sulfate concentration is 0.500 g/L, potassium hydrogen phosphate concentration of 2.000 g/L, the fermentation time is 16 days, the rotate speed of 120 rmp/min by the Box-Behnken test, the yield of product is 0.405 g/L, it is about 2 times higher than initial production 0.138 g/L...