title: Studies on the antioxidant activity of Lippia citriodora infusion: scavenging effect on superoxide radical, hydroxyl radical and hypochlorous acid.
abstract: Lippia citriodora is an herbal species which contains several flavonoids and phenolic acids. In view of the pharmacological interest in natural phenolic compounds as antioxidants, this study examined the superoxide radical, hydroxyl radical and hypochlorous acid scavenging activities of L. citriodora infusion. Superoxide radical was generated either in an enzymatic or in a chemical system, and scavenging ability was assessed by the inhibition of nitroblue tetrazolium reduction. Hydroxyl radical was generated by the reaction of an iron-EDTA complex with H2O2 in the presence of ascorbic acid, and was assayed by evaluating deoxyribose degradation. Hypochlorous acid scavenging activity was tested by measuring the inhibition of 5-thio-2-nitrobenzoic acid oxidation. The results demonstrate that this infusion has a potent superoxide radical scavenging activity and a moderate scavenging activity of hydroxyl radical and hypochlorous acid. The chemical composition of the lyophilized infusion was also determined in an attempt to establish its relationship with the antioxidant activity found in the present study.
authors.affiliation: CEQUP/Laboratory of Pharmacognosy, Faculty of Pharmacy, Porto University, Portugal.
authors.forename: Patricia
authors.initials: P
authors.lastname: Valentão
authors.forename: Eduarda
authors.initials: E
authors.lastname: Fernandes
authors.forename: Félix
authors.initials: F
authors.lastname: Carvalho
authors.forename: Paula Branquinho
authors.initials: PB
authors.lastname: Andrade
authors.forename: Rosa Maria
authors.initials: RM
authors.lastname: Seabra
authors.forename: Maria
authors.initials: M
authors.lastname: de Lourdes Basto
mesh_terms: D000975:Antioxidants / Q000302:isolation & purification / Q000494:pharmacology*; D016166:Free Radical Scavengers / Q000302:isolation & purification / Q000494:pharmacology; D017665:Hydroxyl Radical / Q000378:metabolism*; D006997:Hypochlorous Acid / Q000378:metabolism*; D032411:Lippia; D010936:Plant Extracts / Q000302:isolation & purification / Q000494:pharmacology; D018515:Plant Leaves; D013481:Superoxides / Q000037:antagonists & inhibitors / Q000378:metabolism*
chemical_list: D000975:Antioxidants; D016166:Free Radical Scavengers; D010936:Plant Extracts; D013481:Superoxides; D017665:Hydroxyl Radical; D006997:Hypochlorous Acid