Alia Sadiq, Muhammad Qasim Hayat and Sheeba Murad
Objective: To Determine the phytochemical composition of E. sativa (stem, leaves, flowers and seeds), and evaluate their antioxidant activity.
Method: Preliminary phytochemical screening for all parts of E. sativa (stem, leaves, flowers and seeds) was carried out according to standard methods. Total phenolic contents of all methanolic extracts of E. sativa, have been quantified spectrophotometrically. Hydrogen Peroxidase and 1, 1-diphenyl-2-picrylhydrazyl (DPPH) free radical assays have been used to analyze antioxidant characteristics of all extracts of E. sativa (leaves, stem, seed, flowers and seeds). Further separation and identification of number of phenolic compounds has been carried out by Reversed- Phase High-Performance Liquid Chromatography (RP-HPLC).
Results: Experimental evaluation indicated that E. sativa is a rich source of secondary phytoconstituents (Alkaloids, flavonoids, Diterpenes, Coumarins, polyphenols, tannins, cardiac glycosides etc). Quantification of total phenolic contents from all aerial parts revealed that they contain significant amount of phenolics particularly seeds and leaves (27.1 ± 0.2 mg, 23.07 ± 0.11GAE/g) respectively. Searation and identification of phenolics from E. sativa stem, leaves, flowers and seeds extracts through RP-HPLC showed presence of variety of important phenolics namely; Vanillin (RT=3.853), Ellagic acid (RT=4.04), Salicylic acid (RT=19.09), Resorcinol (RT=3.30), Catechol (RT=3.53), Quercetin (RT=18.91), Benzoic acid (RT=10.4), Tannic acid (RT=5.06), Kaempferol (RT=8.70) and Rutin (RT=9.2).
Conclusion: Results revealed that E. sativa is a rich source of secondary phytoconstituents which impart significant antioxidant potential. This work also contributes significantly to support the claim about the use of this herb in folk medicines. Further investigation regarding isolation and purification of a number of phytoconstituents from leaves, stem, flowers and seeds of E. sativa may yield optimal combinations of therapeutic alternates.