Impact of phenolic composition on hepatoprotective and antioxidant effects of four desert medicinal plants

BACKGROUND Flavonoids and other polyphenols play a protective role in liver diseases and possess a high antioxidant capacity. OBJECTIVE To compare and evaluate the antioxidant and hepatotoprotective activities of 4 deserts plants, Fagonia indica Burm. f., Calotropis procera R.Br., Zygophylum hamiense Schweinf. and Salsola imbricata Forssk. in correlation to their composition especially their phenolic content. METHODS The influence of extracting solvent on total phenolic and flavonoidal contents was assessed spectrophotometrically. The flavonoid and other polyphenolic components of the methanol extracts were analyzed by RP-HPLC. DPPH radical scavenging potential of the different extracts was estimated. The hepatoprotective and antioxidant activities of the extracts against CCl4-induced hepatotoxicity in mice were evaluated. RESULTS The flavonol quercitrin and rosmarinic acid were major in the F. indica, C. procera and S. imbricata samples, while rutin prevailed in that of Z. hamiense. The ethanolic and methanolic extracts showed noticeable DPPH radical-scavenging activity as compared to ascorbic acid. Assessment of liver enzymes revealed that oral administration of the extracts did not show any evidence of hepatotoxicity. Moreover, protection against CCl4-induced liver damage was evident upon administration of three plants extracts namely, F. indica, C. procera and S. imbricata. CONCLUSION Overall, hepatotoxicity induced by CCl4 was effectively prevented by the three plants extracts through scavenging of free radicals and by boosting the antioxidant capacity of the liver. The protective effect of the plants could be attributed to their high quercitrin and rosmarinic acid contents.