In vitro antioxidant activity of Oldenlandia herbacea and isolation of 9,9-dimethyl hexacosane and 23-ethyl-cholest-23-en-3beta-ol.

The petroleum ether, chloroform, ethyl acetate and methanol extracts of the whole plant of Oldenlandia herbacea were screened for in vitro antioxidant activity by using ABTS, DPPH, nitric oxide and hydrogen peroxide assay methods. The chloroform, ethyl acetate and methanol extracts showed potent antioxidant activity against ABTS free radicals. In the hydrogen peroxide method, the methanol and ethyl acetate extracts showed potent activity. Chemical investigation of the petroleum ether extract yielded a long chain hydrocarbon, 9,9-dimethyl hexacosane (1), and a steroid, 23-ethyl-cholest-23-en-3beta-ol (2).