Plantain (Plantago L.) species as novel sources of flavonoid antioxidants.
J Agric Food Chem. 2009 Oct 14 ;57(19):9268-73. PMID: 19754195
Department of Chemistry, Biochemistry and Environmental Protection, Faculty of Sciences, University of Novi Sad, Novi Sad, Serbia. email@example.com
To examine the antioxidant properties of methanol extracts of selected Plantago species (P. argentea Chaix., P. holosteum Scop., P. major L., P. maritima L., and P. media L.), various assays that measure free radical scavenging ability were carried out: DPPH, hydroxyl radical, superoxide anion, and nitric oxide scavenger capacity tests, reducing power (FRAP) assay, and Fe(2+)/ascorbate induced lipid peroxidation. In all of the tests extracts showed a potent antioxidant effect compared with BHT, a well-known synthetic antioxidant, and the extract of P. major, accepted as an official remedy. Besides, in examined extracts the total phenolic amount (ranging from 38.43 to 70.97 mg of GAE/g of dw) and the total flavonoid content (5.31-13.10 mg of QE/g of dw) were determined. Furthermore, the presence and content of selected flavonoids (luteolin-7-O-glucoside, apigenin-7-O-glucoside, luteolin, apigenin, rutin, and quercetin) were studied using LC-MS/MS technique. LC-MS/MS analysis showed noticeable qualitative and quantitative differences between the species according to which the examined Plantago species could be regarded as a possible new source of natural antioxidants. In this study three of the species examined, P. maritima, P. argentea, and P. holosteum, have been analyzed for the first time.