Study On The Growth Characteristics Of Jinhua Fungi And Secretome Analysis Of Its Fermented Tea

Jinhua fungi are the dominant microbes during the fungal growing process of black tea,especially in the process of Fuzhuan tea,which also play an important role in the formation of the quality of Fuzhuan tea.In this study,18 fungal strains were isolated from four different tea samples,Qianliang tea,Fuzhuan tea,Pu-erh tea and liu-pao tea.By plate screening method of screening from these strains produced tannase,amylase,cellulase,lipase,protease,one strain producing many kinds of enzymes and growing faster strain L-7 is screened.Based on the morphology and fungal ITS analysis,the result showed that strain L-7 was identified as Eurotium amstelodami.Using four different media to fermentate the 18 strains of fungi,the results showed that most of the strains grew well on DG18 culture medium.And their colony morphology difference is obvious in different culture medium.On this basis,the effects of different culture conditions and fermentation time on strain L-7 extracellular enzyme production were determined.Using a variety of protein extraction and concentration methods,the protein was enriched.Than SDS-PAGE analysis was applied to test protein extraction.Optimum fermentation conditions for enzyme production as follows:the amount of spore suspension's inoculation is 1 mL,80%moisture content of green tea,fermenting in incubator of 28 ? for 21 days.The best method of extraction and precipitation concentrated total protein were:10%NaCl salt solution leaching fermented tea,filtered supernatant obtained by centrifugation,dialyzed,10%TCA/acetone precipitation,pre-cooled acetone precipitated protein samples obtained.The extracellular proteins from strain L-7 fermented tea leaves were separated by two-dimensionalgel electrophoresis and identified by MOLDI-TOF-TOF.The results showed that there were some enzyme proteins,they were arabinoxylan,superoxide di smutase[Cu,-Zn],tannase,cellulose-binding GDSL lipase,feruloyl esterase,aromatic compound dioxygenase,and glycoside hydrolase enzyme.There were also some functional proteins,such as glycinin G4 subunit,keratin type I cytoskeletal 9 partial and hypothetical protein.