[Dynamic accumulation of three main triterpenic acids in submerged cultivation mycelium of Poria cocos].

ABSTRACT

OBJECTIVE: To study the dymamic accumulation of triterpenic acids production in submerged cultivation mycelium of Poria cocos. METHOD: Liquid culture method of P. cocos was established and RP-HPLC was applied to determine the contents of three main triterpenic acids dehydrotumulosic acid (DTA), 3-epi-dehydrotumulosic acid (eDTA) and polyporenic acid C (PAC) in submerged cultivation mycelium P. cocos at different culture stages and the contents were compared with cultivated P. cocos. The HPLC method is as follows, column Plastisil ODS (4.6 mm x 250 mm, 5 microm); mobile phase ACN/0.5% phosphate (8020); flow rate 1.0 mL . min-1; detective wavelength 242 nm. RESULT: The maximum biomass occurred at the 8th d after inoluctation, however, the contents and yield of three compounds increased till the 17th day. The contents of three compounds were 1. 2% (DTA), 0. 42% (eDTA) and 1.0% (PAC) at the 17th day after inoculation, which were significantly higher than that in cultivated material [0.2% (DTA), 0. 12(eDTA) and 0. 16% (PAC) ]. Furthermore, a correlation analysis between the content ratios of three independent compounds was carried out. The results showed that DTA negatively correlated with eDTA and PAC, with R2 of 0. 857 6 and 0. 971 7, respectively, which suggested the role of DTA as an important intermediate in the biosynthesis of triterpenic acids in P. cocos. CONCLUSION: The sum content of three main terpenoids in submerged cultivation mycelium P. cocos was 5. 55 times as that in cultivated material, which strongly suggested the possibility of fermentation in the production of medicinally important triterpenic acids in the future.