Protective effects of diphenylheptanes from Curcuma phaeocaulis Val. on H2O2 induced cell injury

Curcuma phaeocaulis Val. has been used as a health food in China for a long time. This research aimed to isolate and identify its active compounds with protective effects against hydrogen peroxide-induced PC12 cell death. 70% ethanol extracts of C. phaeocaulis were re-extracted and three fractions of water, petroleum ether and ethyl acetate were obtained. Three diphenylheptane compounds from the ethyl acetate fraction were identified for the first time from C. phaeocaulis, and compound III was considered to be a new structure. All of the three compounds displayed certain protective effects against toxicity in PC12 cells. For all concentrations, compound III displayed a more significant protective effect than ethanol extracts, the ethyl acetate fraction, and the other two compounds. At a concentration of 50 μg mL−1, the survival rate of damaged PC-12 cells treated with compound III reached 84.7%. Diphenylheptanes were concluded to be the main compounds responsible for the health effects of C. phaeocaulis.