title: Phenolics composition and antioxidant activity of sweet basil (Ocimum basilicum L.).
abstract: The antioxidant activity of a methanolic extract of Ocimum basilicum L. (sweet basil) was examined using different in vitro assay model systems. The crude extract was fractionated on a Sephadex LH-20 column, and six fractions were identified. The DPPH scavenging assay system and the oxidation of the soy phosphotidylcholin liposome model system were used to evaluate the antioxidant activity of each fraction. Fraction IV showed the strongest activity followed by fractions V and VI. Phenolic compounds responsible for the antioxidative activity of the fractions were characterized by atmospheric pressure chemical ionization liquid chromatography-mass spectrometry. The major antioxidant compound in fraction IV was confirmed as rosmarinic acid by (1)H NMR and characteristic fragmentations in the mass spectrum. Moreover, the native of antioxidant activity of rosmarinic acid in the liposome system was examined. The results showed that one rosmarinic acid can capture 1.52 radicals, and furthermore, the existence of a synergistic effect between alpha-tocopherol and rosmarinic acid was revealed.
authors.affiliation: Department of Food Science and Technology, Tokyo University of Fisheries, 4-5-7, Konan, Minato-ku, Tokyo 108-8477, Japan.
authors.forename: Chamila
authors.initials: C
authors.lastname: Jayasinghe
authors.forename: Naohiro
authors.initials: N
authors.lastname: Gotoh
authors.forename: Tomoko
authors.initials: T
authors.lastname: Aoki
authors.forename: Shun
authors.initials: S
authors.lastname: Wada
mesh_terms: D000975:Antioxidants / Q000032:analysis*; D001713:Biphenyl Compounds; D005591:Chemical Fractionation; D002851:Chromatography, High Pressure Liquid; D016166:Free Radical Scavengers / Q000032:analysis; D008081:Liposomes / Q000737:chemistry; D000432:Methanol; D018649:Ocimum basilicum / Q000737:chemistry*; D010084:Oxidation-Reduction; D010636:Phenols / Q000032:analysis*; D010713:Phosphatidylcholines / Q000737:chemistry; D010851:Picrates; D010936:Plant Extracts / Q000737:chemistry; D018515:Plant Leaves / Q000737:chemistry*; D013025:Glycine max / Q000737:chemistry
chemical_list: D000975:Antioxidants; D001713:Biphenyl Compounds; D016166:Free Radical Scavengers; D008081:Liposomes; D010636:Phenols; D010713:Phosphatidylcholines; D010851:Picrates; D010936:Plant Extracts; C004931:1,1-diphenyl-2-picrylhydrazyl; D000432:Methanol