Electrochemical and spectroelectrochemical studies of four tanshinones from Salvia miltiorrhiza Bunge

摘要

The spectra of four tanshinones in the potentiostatic reduction process,including tanshinone I,dihydrotanshinone I,tanshinone IIA and cryptotanshinone,were investigated using spectroelectrochemical cell and UV spectrophotometer.Their cyclic voltammograms(CVs)were recorded with a glassy carbon electrode(GCE).The experiment results show that the antioxidant activity of these tanshinones,in the structure,where A,B and C rings connect through a single double bond,is weaker than that where A ring does not have double bond.Moreover,the increasing angle strain in the reduction process could enhance the antioxidant activity.In summary,the rank of antioxidant activities of these tanshinones,from weak to strong,is tanshinone I,dihydrotanshinone I,tanshinone IIA and cryptotanshinone.