Antibacterial, antioxidant and enzyme inhibition activity capacities of Doronicum macrolepis (FREYN&SINT): An endemic plant from Turkey

In the present study, the antioxidant, enzyme inhibition (α-amylase, α-glucosidase, and cholinesterase) and antimicrobial (MIC) activities of three different solvent (ethanol, methanol, or ethyl acetate) extracts of stem, root, and flower of Doronicum macrolepis plant were investigated. In addition to this, the chemical composition and the antimicrobial activity of the essential oil were determined. Antioxidant activity was detected using ABTS and DPPH assays. Antimicrobial activity evaluated by microdilution method against to nineteen microorganisms. Also, enzyme inhibition activities were determined by colorimetric methods. Essential oil of the plant extracted by hydrodistilation and characterized using GC/MS. The antioxidant properties of the flower were determined to be higher than those of the other segments of this plant. Moreover, the total phenolic and flavonoid contents were also found to be higher in the flower parts. The highest enzyme inhibition activity was observed to be α-amylase (221.54 mmol ACAE/g extract) in flower ethylacetate extract, α-glucosidase (15.32 mmol ACAE/g extract) in flower ethanol extract, and cholinesterase (AChE: 2.4 and BChE: 22.35 mg GALE/g extract) in stem ethylacetate extract. Besides them, the antimicrobial activity of the essential oil was found to be higher than the extracts. It showed a high level of inhibition especially on E. coli at 4 µg/ml concentration. Moreover, remarkable inhibition was observed for two candida strains tested. In conclusion, the results suggest that, because of its bioactivity including the antioxidant, antimicrobial, and enzyme inhibition properties, the D. macrolepis can be accepted as a promising and natural source for the industrial applications. The present study is the first study, in which the bioactive components and the antioxidant, antimicrobial, and enzyme inhibition properties of endemic D. macrolepis plant were determined.