Antimicrobial and antioxidant properties of methanol extracts of two Athamanta turbith subspecies

Abstract

The methanol extracts of fruits and leaves of Athamanta turbith subsp. hungarica (Borbas) Tutin (Umbelliferae) and A. turbith subsp. haynaldii (Borbas & Uechtr.) Tutin were analyzed for their antimicrobial and antioxidant properties. Phenolic compounds (flavonoids and phenolic acids) of the extracts were examined using HPLC. All the extracts were characterized by the presence of caffeic acid derivates, luteolin and its glycosides, with luteolin 7-O-glucoside as one of the main compounds. Luteolin 7-O-rutinoside was detected only in A. turbith subsp. haynaldii extracts. Investigation of antimicrobial activity was performed against six bacteria and two fungal strains, using the agar diffusion technique and broth microdilution assay. The extracts of investigated A. turbith subspecies exerted similar antimicrobial activity, whereas the best activity was detected against Candida albicans. In order to investigate antioxidant properties, ferric ion reducing antioxidant power (FRAP), radical scavenging capacity against 2,2-diphenyl-1-picrylhydrazyl (DPPH) and hydroxyl radical (HO.), and the effect on lipid peroxidation (LP) were examined. All the examined extracts showed moderate antioxidant capacity, whereas the fruit extracts were more active than the extracts of leaves. Also, the extracts of A. turbith subsp. hungarica exerted higher antioxidant capacity than corresponding A. turbith subsp. haynaldii extracts. The relationship between estimated activity and chemical composition of the extracts is discussed.