TOTAL PHENOLIC CONTENT, FLAVONOID CONCENTRATION AND ANTIOXIDANT ACTIVITY OF Marrubium peregrinum L. EXTRACTS

In this study, in vitro antioxidant activity, total phenolic content and concentration of flavonoids of five different extracts, from the whole herb of Marrubium peregrinum L. (Lamiaceae) were determined using spectrophotometric methods. Antioxidant activity of extracts were expressed as percentage of DPPH radicals inhibition and IC50 values (μg/ml). Values in percentage ranged from 27.26 to 89.78%. The total phenolic content ranged from 27.26 to 89.78 mg/g of dry weight of extract, expressed as gallic acid equivalents. The total flavonoid concentrations varied from 18.72 to 54.77 mg/g, expressed as rutin equivalents. Methanolic exstract of M. peregrinum showed the highest phenolic and flavonoid concentration and strong antioxidant activity. The significant linear correlation was confirmed between the values for the total phenolic content and antioxidant activity of plant extracts. The high contents of phenolic compounds indicated that these compounds contribute to the antioxidant activity. The M. peregrinum can be regarded as promising candidates for natural plant sources of antioxidants with high value.