In vitro antioksidativno djelovanje nekih Teucrium vrsta (Lamiaceae)

The chemical composition and antioxidant activity of different extracts (diethyl ether, ethyl acetate and n-butanol) obtained from Teucrium species (T. chamaedrys, T. montanum, T. polium) were investigated in this work. Phytochemical screening of the plant extracts proved the presence of flavonoids: luteolin, apigenin and/or diosmetin. The chemical composition of extracts was evaluated by HPLC and spectrophotometry. Antioxidant activities of the extracts were evaluated using three complementary in vitro assays: inhibition of DPPH (1,1-diphenyl-2-picrylhydrazyl) radical, inhibition of hydroxyl radicals and protection of beta-carotene-linoleic acid model system. In the first two assays, strong inhibitory activity was shown by T. montanum and T. chamaedrys extracts. In the beta-carotene-linoleic acid model system, extracts from T. polium showed remarkable activity. These findings demonstrated that Teucrium species possess free radical and hydroxyl radical scavenging activity as well as antioxidant activity in vitro.U radu je opisan kemijski sastav i antioksidativno djelovanje različitih ekstrakata (dietil-eter, etil-acetat, n-butanol) iz Teucrium vrsta (T. chamaedrys, T. montanum, T. polium). Fitokemijska istraživanja ekstrakata HPLC metodom i spketrofotometrijom pokazala su prisutnost flavonoida luteolina, apigenina i/ili diosmetina. Antioksidativni učinci ekstrakata praćeni su in vitro pomoću tri komplementarne metode koje se temelje na inhibiciji DPPH (1,1-difenil-2-pikrilhidrazil) radikala, inhibiciji hidroksil radikala ili na zaštiti sustava -karoten-linoleinska kiselina. U prva dva modela dokazan je snažni inhibitorni učinak ekstrakata vrsta T. montanum, T. chamaedrys, dok su u trećem modelu ekstrakti iz T. polium pokazala značajni učinak. Rezulati ukazuju da Teucrium vrste imaju sposobnost vezanja slobodnih i hidroksil radikala i antioksidativni učinak in vitro