Isolation and purification of apigenin, quercetin and apigenin 7-O-glycoside from Apium graveolens L., Petroselinum crispum (Mill.) Fuss, Allium cepa L., respectively

Abstract

Background: Flavonoids, a group of natural substances, are found in flowers, fruits, roots and stems. These natural products are well known for their health-beneficial effects. Hence, isolation and purifying of flavonoids from the ingredients is worthwhile. Flavonoids are now considered indispensable in various nutraceutical, pharmaceutical, medicinal and cosmetic applications. Apigenin, quercetin, and apigenin-7-O-glycoside have therapeutic properties that these two are in the flavonoid group. Objectives: In this study, apigenin, quercetin, and apigenin 7-O-glycoside were purified by column chromatography and identified by NMR and HPLC UV-visible techniques. Methods: Total extracts of three plants (Apium graveolens, Petroselinum crispum, Allium cepa) were divided into different solvent fractions. Column chromatography is used to purify these fractions. Finally, 1H-NMR, 13C-NMR, and mass spectrometry techniques were used for identification. Also, the HPLC technique was used for identifying these compounds and standardized. Results: In the present work, apigenin was extracted from ethyl acetate fraction of Apium graveolens seeds. High purity of apigenin 7-O-glycoside isolated from the butanol fraction of Petroselinum crispum aerial parts. Also, ethyl acetate fraction isolated quercetin from the Allium cepa. Identification of the data obtained from 1H-NMR and 13C-NMR, which were proofed by comparison with the sources of purified compounds. Conclusion: The methods used in this research were able to produce these three compounds with a high percentage of purity to be used in industry as standards.