Metabolomics and Biological Activities of Residual Parts from Some Egyptian Green Vegetables

SEARCHING for natural alternatives to replace the synthetic pharmaceuticals, investigations for active metabolites ith biological activities in different plant parts (seeds, grains, fruits, peels of fruits, roots, rhizomes and green vegetables) are always of great importance and interest. As an example of the nutritional leafy vegetables, Corchorus olitorius and Portulaca oleracea are widely distributed and eaten by many countries. These plants constitute the material of interest in this study. Extraction of the leafy vegetables was carried out by methylene chloride: methanol mixture (2:1 v/v). The extract was subjected to analyse their antioxidant and anticancer efficiencies. Three methods were used for antioxidant activity determination including DPPH (2,2-diphenylpicrylhydrazyl), ABTS (2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid), and KMnO4 (potassium permanganate). P. oleracea extract showed the greatest antioxidant activity by the three methods (86.55, 82.75 and 97.62%, respectively) compared to both C. olitorius (75.98, 57.02 and 34.98% respectively) and standard ascorbic acids (76.42, 73.93 and 99.09% respectively) at 100 mu g/ml. C. olitorius extract exhibited highest cytotoxicity against HepG2 (Human liver cancer cell line) compared to both P. oleracea and the anticancer drug Doxorubicin. Gas chromatography/Mass spectroscopic analysis revealed that the leafy vegetable extracts contain 15 and 18 phytochemical compounds (in P. oleracea and C. olitorius, respectively) and the monounsaturated fatty acid oleic acid was the major constituent with 4244.69%. The active groups in the phytochemicals were analyzed by FTIR technique. From this study, we recommend P. oleracea extract to be used as source of antioxidant agents, while C. olitorius extract can be considered as an anticancer active vegetable.