Antioxidant and lipophilic constituents of Tinospora crispa.

TLC autographic assays revealed in the CH(2)Cl(2) extract of Tinospora crispa Miers (Menispermaceae) the presence of three compounds exhibiting antioxidant and radical scavenging properties towards beta-carotene and 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical. They were isolated and identified as N-CIS-feruloyltyramine, N-trans-feruloyltyramine and secoisolariciresinol. When tested in dilution assays on the reduction of the DPPH radical, these 3 compounds proved to be more active than the synthetic antioxidant butylhydroxytoluene (BHT). Further investigation of the CH(2)Cl(2) extract led to the isolation of vanillin, syringin, the alkaloid N-formylnornuciferin and the diterpene derivatives borapetosides B and C. In addition, a LC/UV/MS analysis enabled the on-line identification of borapetoside F and N-formylannonain.