Studies on the chemical constituents, antioxidants and membrane stability activities of Hibiscus rosa sinensis

The chemical constituents, antioxidant and membrane stability activities of Hibiscus rosa sinensis Linn. (Malvaceae) flower were determined. The total anthocyanin was 165 mg / kg with about 6 % reduction due to fermentation. Tannin, ascorbic acid, and total polyphenol were 11.8 g / kg; 478 mg / kg; and 14.4 mg / g, respectively. The phytochemical screening revealed the presence of alkaloids and saponins. The antioxidant activity of the extract was significantly lower (EC50 = 43.9 μg / mL) compared to ascorbic acid (E 50 = 3.3 μg / mL). The extract of fermented Hibiscus rosa sinensis exhibited a concentration dependent, biphasic membrane stability of 46.2 % at 1.0 mg / mL and stability of 63.6 % at 2.0 mg / mL. The study indicated that the flower could be a good source of dietary antioxidant and stabilized red blood cells exposed to induced lyses.