Phenolic profile, antioxidant capacity of five Z<i>iziphus spina</i>-<i>christi</i> (L.) Willd provenances and their allelopathic effects on <i>Trigonella foenum</i>-<i>graecum</i> L. and <i>Lens culinaris</i> L. seeds

<p>The aim of this work was to evaluate some secondary metabolites, antioxidant activity of methanolic leaf extracts of five <i>Ziziphus spina</i>-<i>christi</i> provenances (INRGREF, Tozeur, Degueche, Nafta and Kebelli) and their allelopathic effects on <i>Trigonella foenum</i>-<i>graecum</i> and <i>Lens culinaris</i>. Leaves were collected during 2013 and 2014. Total phenols, flavonoids, tannins and antioxidant activity were evaluated using the Folin ciocalteux, Aluminum trichloride, vanillin and scavenging activity on 22-diphenyl-1-picrylhydrazyl (DPPH) radical methods, respectively. Total phenols, tannins and flavonoids were present, at levels of 57.41 mg GAE/g DW, 31.98 mg RE/g DW and 14.68 μg CE/g DW, respectively. The high antioxidant activity (0.086 μg/mL) was noted in kebelli provenance (2013). The highest germination, plumule and radicle lengths of tested species were observed in INRGREF provenance. <i>Z. spina</i>-<i>christi</i> leaf extracts may be suggested in foods and pharmaceutical industries. Leaf extracts could also provide a natural herbicide with a positive impact on the environment.</p