Abstract

PHYTOCHEMICAL SCREENING, EVALUATION OF ANTIOXIDANT ACTIVITY AND LITHOLYTIC EFFECT OF ZIZYPHUS LOTUS L. EXTRACTS

Khouchlaa Aya*, Bouyahya Abdelhakim, Ait Lahcen Samira, Youssef Bakri, Nadia Dakka and Tijane M’hamed

Abstract

Zizyphus lotus L., a shrub belonging to the family Rhamnaceae, is usedin Morocco for different therapeutic purposes. In order to valorize thisplant, firstly, we have determined the total phenol and flavonoidcontents of Z. lotus leaves extracts. Secondly, we have evaluated theantioxidant activity of Z. lotus leaves extracts and their efficacy ondissolution of kidney stones. The total phenol and flavonoid contentsof Z. Lotus leaves extracts were respectively determined by the Folin-Ciocalteu and aluminum trichloride (AlCl3) method. The antioxidantactivity is determined with the DPPH radical trapping method. Thelevel of polyphenols varies between 23.11 and 23.94 mg GAE (Gallicacid equivalent)/ mg GAE/ g of extract. While those flavonoids varybetween 12.68 and 104.12 mg QE (Quercetin equivalent)/ mg QE/g of extract. Thedichloromethane extract has the highest flavonoid content 104.68 mg QE (Quercetinequivalent)/mg of extract. The antioxidant activity test shows that the methanol extract wasthe most active with an IC50=0.7 mg/mL. In the in vitro study, we observed that the aqueousextract had a greater dissolving effect on uric acid stones (17%) than on calcium oxalatestones. These results suggest the quality phenolic compounds from leaves of Z. lotus leaveswith antioxidant properties are suggesting the of this plant use in food preservation againstoxidation. In all, its therapeutic application requires thorough study of the active ingredient 

Keywords: Zizyphus lotus L., antioxydante activity, polyphénols, flavonoids, calcium oxalate, uric acid.