Objective:To determine the chemical composition, total phenolic and total flavonoid contents of the crude extracts from leaves and stems of a Lebanese plant Euphorbia macroclada schyzoceras (E. macroclada), and to evaluate their antioxidant potential using DPPH, H2O2, and chelating of ferrous ions tests. Methods:Quantification of the total phenolic and total flavonoid contents of the crude extracts from leaves and stems and the antioxidant activities were evaluated using spectrophotometric analyses. The chemical composition has been estimated using different techniques such as IR, LC/MS and NMR. Results:Ethanolic extract from leaves of E. macroclada was better than aqueous extract and showed higher content in total phenolic and total flavonoid than found in the stems. On the other hand, using DPPH and H2O2 tests, this extract from leaves showed higher antioxidant capacity than aqueous extract. However, using the chelating of ferrous ions test, the antioxidant activity of the aqueous extract of both stems and leaves was stronger than that of ethanolic once. The chemical composition of the whole plant showed the presence of some aromatic compounds and fatty acids. Conclusions:Both ethanolic and water extracts from both parts of this plant are effective and have good antioxidant power. So, this plant can be used in the prevention of a number of diseases related to oxidative stress.

Objective: To determine the phytochemical screening and quantification of total phenolics contents in fresh Eryngium creticum (E. creticum) leaves and stems extract and to evaluate its total antioxidant activity. Methods: Quantification of total phenolics contents in fresh E. creticum leaves and stems extract and evaluation of its total antioxidant activity, were done using the spectrophotometric analyses. Results: The consumption of 100 g of fresh E. creticum leaves and stems could provide antioxidants equivalent to (78.50±0.80) mg of vitamin C and (50.42±0.50) mg of vitamin C, respectively. Conclusions: From this study, it can be concluded that E. creticum can be interesting to prevent diseases directly linked to oxidative stress.