title: Antioxidant activities and polyphenolic contents of three selected Micromeria species from Croatia.
abstract: Antioxidant activities of three selected Micromeria species growing in Croatia (M. croatica, M. juliana and M. thymifolia) were evaluated using five different antioxidant assays, in comparison with plant polyphenolic constituents and reference antioxidants. All studied ethanolic extracts exhibited considerable activity to scavenge DPPH and hydroxyl free radicals, reducing power, iron chelating ability and total antioxidant capacity in the order: M. croatica > M. juliana > M. thymifolia. Total polyphenol (9.69-13.66%), phenolic acid (5.26-6.84%), flavonoid (0.01-0.09%) and tannin (3.07-6.48%) contents in dried plant samples were determined spectrophotometrically. A strong positive correlation between antioxidant activities and contents of phenolic acids and tannins was found, indicating their responsibility for effectiveness of tested plants. Our findings established Micromeria species as a rich source of antioxidant polyphenols, especially the endemic M. croatica.
authors.affiliation: Department of Pharmacognosy, Faculty of Pharmacy and Biochemistry, University of Zagreb, Marulićev trg 20, HR-10000 Zagreb, Croatia. sanda@pharma.hr
authors.forename: Sanda
authors.initials: S
authors.lastname: Vladimir-Knežević
authors.forename: Biljana
authors.initials: B
authors.lastname: Blažeković
authors.forename: Maja Bival
authors.initials: MB
authors.lastname: Štefan
authors.forename: Antun
authors.initials: A
authors.lastname: Alegro
authors.forename: Tamás
authors.initials: T
authors.lastname: Koszegi
authors.forename: József
authors.initials: J
authors.lastname: Petrik
mesh_terms: D000975:Antioxidants / Q000737:chemistry*; D017523:Croatia; D005419:Flavonoids / Q000737:chemistry*; D016166:Free Radical Scavengers / Q000737:chemistry; D062385:Hydroxybenzoates / Q000737:chemistry; D019686:Lamiaceae / Q000737:chemistry*; D010636:Phenols / Q000737:chemistry*; D010936:Plant Extracts / Q000737:chemistry*; D059808:Polyphenols; D013634:Tannins / Q000737:chemistry
chemical_list: D000975:Antioxidants; D005419:Flavonoids; D016166:Free Radical Scavengers; D062385:Hydroxybenzoates; D010636:Phenols; D010936:Plant Extracts; D059808:Polyphenols; D013634:Tannins; C017616:phenolic acid