title: Antioxidant flavan-3-ols and flavonol glycosides from Maytenus aquifolium.
abstract: TLC autographic assay revealed, in the EtOAc extract obtained from leaves and root bark of Maytenus aquifolium (Celastraceae), the presence of fi ve compounds exhibiting antioxidant properties towards beta-carotene. They were isolated and identified as epigallocatechin (1), (+) ouratea-catechin (2), proanthocyanidin (3), kaempferol 3-O-alpha-L-rhamnopyranosyl (1-->6)-O-[beta-D-glucopyranosyl (1-->3)-O-alpha-L-rhamnopyranosyl-(1-->2)]-O-beta-D-glucopyranosyl (4) and quercetin 3-O-alpha-L-rhamnopyranosyl (1-->6)-O-[beta-D-glucopyranosyl (1-->3)-O-alpha-L-rhamnopyranosyl-(1-->2)]-O-beta-D-glucopyranosyl (5). The isolates were investigated for their redox properties using cyclic voltammetry and for their radical scavenging abilities through spectrophotometric assay on the reduction of 2,2-diphenyl-pycryl hydrazyl (DPPH). These results were correlated to the inhibition of beta-carotene bleaching on TLC autographic assay and to structural features of the flavonoids.
mesh_terms: D000975:Antioxidants / Q000008:administration & dosage / Q000494:pharmacology* / Q000627:therapeutic use; D001713:Biphenyl Compounds; D004563:Electrochemistry; D005419:Flavonoids / Q000008:administration & dosage / Q000494:pharmacology* / Q000627:therapeutic use; D044948:Flavonols / Q000008:administration & dosage / Q000494:pharmacology* / Q000627:therapeutic use; D006027:Glycosides / Q000008:administration & dosage / Q000494:pharmacology* / Q000627:therapeutic use; D006801:Humans; D029755:Maytenus; D008517:Phytotherapy; D010851:Picrates; D010936:Plant Extracts / Q000008:administration & dosage / Q000494:pharmacology / Q000627:therapeutic use; D018515:Plant Leaves; D018517:Plant Roots; D019207:beta Carotene / Q000737:chemistry
chemical_list: D000975:Antioxidants; D001713:Biphenyl Compounds; D005419:Flavonoids; D044948:Flavonols; D006027:Glycosides; D010851:Picrates; D010936:Plant Extracts; D019207:beta Carotene; C404987:flavan-3-ol; C004931:1,1-diphenyl-2-picrylhydrazyl