THE STUDY OF ANTIOXIDANT ACTIVITY OF BIOLOGICALLY ACTIVE SUBSTANCES IN THE ALCOHOL EXTRACT OF NETTLE LEAVES

Abstract

The purpose of this research is the extraction of phenolic compounds from nettle leaves, grown in urban conditions, with different concentrations of ethanol and the study of the antioxidant properties of these extracts. Nettle (Urtica dioica) is a great source of bioactive compounds. The content of biologically active compounds in nettle leaves depends on the growing conditions of the plant. Analysis of the electronic spectra of the extract shows that all extracts contain aurones and coumarins, hydroxybenzoic acid and flavonoids. The antioxidant activity (AO) of polyphenols in alcoholic extracts of nettle was studied using the stable radical 2,2-diphenyl-1-picrylhydrazyl (DPPH). It was found that the total amount of biologically active substances is greatest in a 70% ethanol solution of nettle leaves, but the antioxidant activity is higher in a 95% solution. The total amount of flavonoids in the leaves of urban nettles is higher than in the leaves of the nettle grown in the meadow. Perhaps this is connected with the process of the plant’s protective mechanisms caused by air pollution in the city.