Phytochemical, antioxidant and antimicrobial profiles of extracts of Daphne alpina (Thymelaeaceae) L leaf and twig from mt kopaonik (Serbia)

Abstract

© Pharmacotherapy Group. Purpose: To investigate the phytochemical composition, as well as antioxidant and antimicrobial activities of the leaf and twig extracts of Daphne alpina L. (Thymelaeaceae). Methods: The dry chloroform and methanol extracts of the leaf and twigs of Daphne alpinа were used for analysis. Total phenolic and flavonoid contents were determined by established procedures. Antioxidant potential was investigated by several methods. The antimicrobial properties of the extracts were obtained by microdilution method. High performance liquid chromatography (HPLC) was employed for the identification of the most abundant metabolites, present in D. alpina extracts. Results: The total phenolics of the extracts ranged from 78.98 to 88.98 mg GA/g while total flavonoids were in the range 28.09 to 34.65 mg GA/g of fresh weight. HPLC analysis of the extracts showed the presence 4-hydroxybenzoic acid, 7,8-dihydroxycoumarine and 7-hydroxycoumarine. Total antioxidant capacity ranged from 69.71 μg AA/g for the methanol leaf extract to 73.55 μg AA/g for the chloroform twig extract. All the extracts showed DPPH radical scavenging activity (21.57 - 25.45 μg/mL), inhibitory activity against lipid peroxidation (26.79 - 35.24 μg/mL), ferrous ion chelating ability (21.57 - 45.45 μg/ml) and hydroxyl radical scavenging activity (87.98 - 98.86 μg/mL). Minimum inhibitory concentration (MIC) was in the range 15.62 - 125 μg/mL. Conclusion: The extracts possess moderate antioxidant and antimicrobial activities due probably to the phenolic compounds in the extracts.