Isolation, purification and identification of antioxidants from Lepidium latifolium extracts

In this study, we found that the ethyl acetate soluble fraction ofL. latifolium was a rich source of antioxidant, resulting from its high total phenolic content. To determine the antioxidant components of the ethyl acetate fraction, a bioassay-guided fractionation approach using 1,1-diphenyl-2-picrylhydrazyl, 2,2 ′-azinobis-(3-ethylbenzthiazoline-6-sulfonate), and ferric reducing antioxidant power assays were conducted. Nine compounds were isolated and their structures were identified by MS and NMR spectral data and comparison to reported data. They are Quercetin-3-O-β-d-sophoroside-7-O- α-l-rhamnoside (1), Apetalumoside B6 (2), Kaempferol-3-O- β-d-glucopyranosyl-(1-2)- β-d-glucopyranoside-7-O- β-d-glucopyranoside (3), Kaempferol-7-O- α-l-rhamnopyranoside (4), Kaempferol-3-O- β-d-glucopyranoside-7-O- α-l-rhamnopyranoside (5), Kaempferol-3-O-(2-O-feruloyl- β-d-glucopyranosyl-(1-2)- β-d-glucopyranoside)-7-O-glucopyranoside (6), Kaempferol-3-O- β-d-sophoroside-7-O- α-l-rhamnoside (7), Kaempferol-3-O-robinoside-7-O-(2 ″″-(E)-feruloyl)-sophoroside (8), Quercetin-3-O-(2,6-di-O- β-d-glucopyranosyl)- β-d-glucopyranoside-7-O- α-l-rhamnopyranoside (9), compounds1,2,4, and8 had potent free radical scavenging activity. The IC50 values of these compounds were 9.8 –12.3 and 7.4–31.4 μg/mL in DPPH and ABTS assays, respectively. The results indicate thatL. latifolium is a potential natural source of antioxidants to treat several diseases related to oxidant by-prod...
Source: Medicinal Chemistry Research - Category: Chemistry Source Type: research