Antioxidant, Hepatoprotective, and Antidepression Effects of<i> Rumex tingitanus</i> Extracts and Identification of a Novel Bioactive Compound

Abstract

Over the last few decades, <i>Rumex</i> species have been recognized as a promising source of new compounds with numerous pharmacological activities. Therefore, the antioxidant activity of <i>Rumex tingitanus (R. tingitanus)</i> leaves extracts was evaluated <i>in vitro</i> and then confirmed <i>in vivo</i> as well as the antidepressant-like and toxicological effects of the extracts. The ethyl acetate fraction (Rt EtOAcF) followed by hydroalcoholic extract (Rt EtOH-H₂O) showed a remarkable <i>in vitro</i> antioxidant activity. The hydroalcoholic extract (Rt EtOH-H₂O) showed significant hepatoprotective activity against carbon tetrachloride- (CCl₄-) induced liver toxicity which is seen from inhibition of the malondialdehyde (MDA) accumulation and enhancement of the liver antioxidant enzymes activities. The Rt EtOH-H₂O and Rt EtOAcF extracts were able to reduce the immobility time in mice and then elicited a significant antidepressant-like effect. The ethyl acetate fraction (Rt EtOAcF) was purified and resulted in the identification of a new antioxidant component called 4'-<i>p</i>-acetylcoumaroyl luteolin. The Rt EtOAcF and the 4'-<i>p</i>-acetylcoumaroyl luteolin revealed a strong antioxidant activity using DPPH test with IC₅₀ of 11.7 ± 0.2 and 20.74 ± 0.6 <i>μ</i>g/ml, respectively, and AAI of 3.39 and 1.92 better than that of BHT, used as control.