Chemical composition and antioxidant activity of a Lebanese plant Euphorbia macroclada schyzoceras

Objective:To determine the chemical composition,total phenolic and total flavonoid contents ofthe crude extracts from leaves and stems of a Lebanese plantEuphorbia macroclada schyzoceras(E.macroclada),and to evaluate their antioxidant potential using DPPH,H2O2,and chelating offerrous ions tests.Methods:Quantification of the total phenolic and total flavonoid contents ofthe crude extracts from leaves and stems and the antioxidant activities were evaluated usingspectrophotometric analyses.The chemical composition has been estimated using differenttechniques such as IR,LC/MS and NMR.Results:Ethanolic extract from leaves ofE.macroclada was better than aqueous extract and showed higher content in total phenolic and total flavonoidthan found in the stems.On the other hand,using DPPH and H2O2tests,this extract from leavesshowed higher antioxidant capacity than aqueous extract.However,using the chelating of ferrousions test,the antioxidant activity of the aqueous extract of both stems and leaves was strongerthan that of ethanolic once.The chemical composition of the whole plant showed the presence ofsome aromatic compounds and fatty acids.Conclusions:Both ethanolic and water extracts fromboth parts of this plant are effective and have good antioxidant power.So,this plant can be usedin the prevention of a number of diseases related to oxidative stress.

巨枝大戟化学成分的研究

从巨枝大戟（ Ｅｕｐｈｏｒｂｉａ ｍａｃｒｏｃｌａｄａ ）的全草中分离得到１０ 个化合物，分别鉴定为：１ ，２∶５ ，６二氧异丙叉基αＤ呋喃葡萄糖甙（１） ，１，２∶４ ，５二氧异丙叉基βＤ吡喃果糖甙（２），１ ，２氧异丙叉基αＤ呋喃葡萄糖甙（３），１ ，２氧异丙叉基βＤ吡喃果糖甙（４） ，５羟甲基糠醛（５） ，５甲氧基甲基糠醛（６） ，Ｄ葡萄糖（７） ，β谷甾醇（８） ，β胡萝卜甙（９） ，乔木萜醇（１０） ．其中１ ～７ 为首次从大戟属植物中分离得到．