Investigation of antioxidant and antimicrobial activities of medicinal plants grown in the eastern black sea region of Turkey

Abstract

Objective: The aim of this study was to screen various extracts of plant of Gentian ( Gentiana pyrenaica L . ), Tarragon ( Artemisia dracunculus L.), Persimmon ( Diospyros kaki ), Raspberry ( Rubus ideaus ) to display potent antimikrobial, antifungal and antioxidant activity in vitro, total phenolic and flavonoid contents in order to find possible sources for future novel antioxidants in food and pharmaceutical formulations. Material and Methods: The antioxidant properties of 12 different samples of medicinal and aromatic plants such as leaves, flowers and scapus were investigated by DPPH, FRAP and CUPRAC assays. Total phenolic, total flavonoid content and the antimicrobial properties of extracts from these plants were also determined. Antibacterial and antifungal activities were investigated by microdilution method and agar diffusion method respectively. Results: According to the determination of antioxidant results, dried leaves of Persimmon ( Diospyros kaki ) (obtained from Trabzon) plant had the best antioxidant activity that was carried out in all analyzes (except the analysis of total polyphenol). In accordance with analysis of total polyphenol, activity of purple flower of Gentian ( Gentiana pyrenaica L . ) plant was measured at 31,303±0,274 mg GAE /g dry sample and thus this plant had the highest total phenolic content. Antimicrobial activity tests were carried out using disc diffusion methods with 12 microbial species and most of them displayed good-moderate antimicrobial activity. Conclusion: Due to their antimicrobial, antifungal and antioxidant properties, the extracts some of these plants might be used as potential sources of natural antioxidant and antimicrobial agents.