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 alpina 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.
