Abstract
The aim of this work was to evaluate phenolic profile, antioxidant capacity and allelopathic effects of six Ziziphyus spina- christi provenances in Saudi Arabia. Total phenols, flavonoids, tannins and antioxidant activity were evaluated. Total phenols, condensed tannins and total flavonoids were present at levels of 62.29 mg GAE/g DM, 16.69 mg CE/g DM and 15.45 mu g mg QE/g DM, respectively. The high antioxidant activity (0.15 mg/ml) was noted in Mecca Road provenance. The highest germination, shoots and radicle lengths of tested species were observed in At-taif provenance. Z. spina - christi 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. Provenance of Jizan, Northern Borders and Mecca Road were shown to be particularly effective in antioxidant capacity, while Provenance of Riyadh and Northern Borders shown to have the best allelopathic activity.