title: Immortelle (Xeranthemum annuum L.) as a natural source of biologically active substances.
abstract: Antioxidant and antimicrobial effects, total phenolic content and flavonoid concentrations of methanolic, acetone and ethyl acetate extracts fromXeranthemum annuumL. were investigated in this study. The total phenolic content was determined using Folin-Ciocalteu reagent and ranged between 101.33 to 159.48 mg GA/g. The concentration of flavonoids in variousX.annuumextracts was determined using spectrophotometric method with aluminum chloride and the results varied from 22.25 to 62.42 mg RU/g. Antioxidant activity was monitored spectrophotometrically using DPPH reagent and expressed in terms of IC50(µg/ml), and it ranged from 59.25 to 956.81 µg/ml. The highest phenolic content and capacity to neutralize DPPH radicals were found in the acetone extract.In vitroantimicrobial activity was determined by microdilution method. Minimum inhibitory concentration (MIC) and minimum microbicidal concentration (MMC) have been determined. Testing was conducted against 24 microorganisms, including 15 strains of bacteria (standard and clinical strains) and 9 species of fungi. Statistically significant difference in activity between the extracts ofX. annuumL. was observed and the acetone extract was found most active. The activity of acetone extract was in accordance with total phenol content and flavonoid concentration measured in this extract. The tested extracts showed significant antibacterial activity against G+ bacteria and weak to moderate activity against other microorganisms. Based on the obtained results,X. annuumcan be considered as a rich natural source of polyphenolic compounds with very good antioxidant and antimicrobial activity.
authors.affiliation: Department of Biology and Ecology, Faculty of Science, University of Kragujevac, Radoja Domanovica 12, 34000 Kragujevac, Republic of Serbia.
authors.forename: Milan S
authors.initials: MS
authors.lastname: Stankovic
authors.affiliation: Department of Biology and Ecology, Faculty of Science, University of Kragujevac, Radoja Domanovica 12, 34000 Kragujevac, Republic of Serbia.
authors.forename: Ivana D
authors.initials: ID
authors.lastname: Radojevic
authors.affiliation: Department of Biology and Ecology, Faculty of Science, University of Kragujevac, Radoja Domanovica 12, 34000 Kragujevac, Republic of Serbia.
authors.forename: Olgica D
authors.initials: OD
authors.lastname: Stefanovic
authors.affiliation: Department of Biology and Ecology, Faculty of Science, University of Kragujevac, Radoja Domanovica 12, 34000 Kragujevac, Republic of Serbia.
authors.forename: Marina D
authors.initials: MD
authors.lastname: Topuzovic
authors.affiliation: Department of Biology and Ecology, Faculty of Science, University of Kragujevac, Radoja Domanovica 12, 34000 Kragujevac, Republic of Serbia.
authors.forename: Ljiljana R
authors.initials: LR
authors.lastname: Comic
authors.affiliation: Department of Biology and Ecology, Faculty of Science, University of Kragujevac, Radoja Domanovica 12, 34000 Kragujevac, Republic of Serbia.
authors.forename: Snežana R
authors.initials: SR
authors.lastname: Brankovic
keywords: Xeranthemum annuum; antimicrobial capacity; antioxidant; flavonoids; immortelle; phenols