The Process Regulation Of The Fermentation Of Triterpenoids By Liquid Fermentation Of Sputum And The Antioxidation Of The Fermentation Broth

Objective:?1?To explore the biosynthesis rules of Poria cocos triterpene in liquid fermentation system,and select the optimal medium composition.?2?To research the effect of methyl jasmonate on the Poria cocos triterpenes biosynthesis,screen out the optimal control conditions of MeJA in the biosynthesis of Poria cocos triterpene and find the mechanism in molecular level.?3?To explore the antioxidant activity of Poria cocos organic extracts base on Poria cocos triterpenes dissolving easily in organic phase.Methods:?1?Single factor experiment design was employed to discuss the influences of carbon source,nitrogen source,metal ion,cofactor and initial pH on cell growth and trierpenoids concentration in submerged fementation system,respectively.?2?The effects of addition amount and feeding time of MeJA on Poria cocos triterpenoid biosynthesis were discussed,respectively.Besides,to illustrate regulation mechanism of MeJA,real time PCR?RT-PCR?was employed to analysis the expression level of fps and sqs in mevalonate?MVA?pathway of Poria cocos.?3?The antioxidative activities of liquid fermentation Poria cocos methanol extract,methanol heating reflux extract and ethyl acetate heating reflux extract were investigated respectively,which provided the theoretical basis for further research and development of Poria cocos triterpenoid.Results:?1?fininal results showed that glucose used as carbon source,corn pulp powder used as nitrogen source,ZnSO₄,MnSO₄,CuSO₄ and FeSO₄ used as metal ions,2-thiobarbituric acid as cofactor and initial pH 5-6 were the optimal cultivation conditions for tritepenoid biosynthesis.?2?The best regulation method of MeJA is adding 150?M MeJA on the 4 day into Poria cocos shaking culture,and the Poria cocos triterpenes content is 20.85 mg/L,the relative expression of sqs,fqs are 788.70,1.17 respectively.MeJA can induce the Poria cocos triterpenes biosynthesis significantly,especially regulate sqs expression level.?3?The organic extracts of Poria cocos had significant scavenging ability on DPPH·and H₂O₂·,and the antioxidant activity of the extracts extracted by methanol by methanol and warm-up and reflu was the strongest,but those Poria cocos organic phase extractshad no antioxidant effect on O₂^-.Conclusion:?1?The optimum medium composition was screened,next step can further optimize the proportion of the medium components of the optimum Poria cocos triterpenes biosynthesis.?2?Selected the best MeJA conditions for Poria cocos triterpenes biosynthesis,and explained its mechanism from the molecular level,the later can further pelore the inducer influence on Poria cocos triterpenes biosynthesis in the liquid fermentation system,provide theoretical support for screening inducer.?3?The antioxidant activity of organic extracts of Poria cocos was preliminarily investigated,the triterpenes in organic extracts could be separated and purified to analyze and compare the different antioxidant activity between Poria cocos triterpenes components.