Comparison of the protective effects of seven selected herbs against oxidative stress

Objective:To compare the protective effects of the water extracts of seven herbs,including Solanum indicum L.,Mallotus repandus(Wild)Muell-Arg.(MRM),Bombax malabarica DC(BMDC),Tadehagi triquetrum(L.)Ohashi(TTLO),Clinacanthus nutans(Burm f.)Lindau,Salvia plebeia R.Br(SPRB),Ixeris chinensis Mak(ICM),against tert-butylhydroperoxide(t-BHP)-induced oxidative stress in Clone 9 cells.Methods:To evaluate the antioxidant properties of water extracts from seven herbs,reducing ability,metal-chelating activity and radical-scavenging activity such as 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid)radical cation and 1,1-diphenyl-2-picrylhydrazyl(DPPH)were determined.In cellular systems,t-BHP was used as a model oxidant to induce oxidative stress.2′,7′-Dichlorofluorescin diacetate and chloromethylfluorescein-diacetate were used as fluorescence probe to determine reactive oxygen species generation and glutathione level in t-BHP-induced Clone 9 cells,respectively.In addition,total tannins,total anthocyanins,total polyphenolics and flavonoids were determined.Results:According to the data obtained from the trolox equivalent antioxidant capacity method,DPPH radical scavenging assay and reducing ability determination,MRM,SPRB,and BMDC showed relatively high antioxidant properties while TTLO and ICM were in the middle and Solanum indicum and Clinacanthus nutans had relatively low activity.In cellular model systems,SPRB,BMDC,and TTLO showed higher protective effects against t-BHP-induced oxidative stress.BMDC,ICM,and TTLO displayed higher inhibitory effects on reactive oxygen species generation in t-BHP-induced Clone 9 cells.In addition,SPRB,MRM,and BMDC showed significantly positive modulated glutathione levels.Tannins,anthocyanins,flavonoids and polyphenolics were present in the herbs,which may in part contribute to regulating the oxidative stress.Conclusions:These results indicated that the seven selected herbs may play a crucial role in regulating oxidative stress,especially BMDC.