Shaida Fariza SULAIMAN, Amir Modorresi CHAHARDEHI, Darah IBRAHIM

Antioxidant Activity and Total Phenolic Content of Some Medicinal Plants in Urticaceae Family

Fifteen different extracts from the leaves of Urtica d ioica, Pilea microphylla and Elatostema umbellatum were examined for phenolics content and free radical scavenging capacity, to determine their potential as a source of natural antioxidants. The highest DPPH radical scavenging percentages were showed by the butanol and ethyl acetate extracts Urtica dioica that are 62.537 ± 5.069% and 62.177 ± 2.987% at concentration 1000 µg/ml, respectively. Total phenolic content ranged from 0.24 ± 0.15 to 100.30 ± 0.01 mg gallic acid/g dry weight. The ethyl acetate extract of Urtica dioica exhibited the lowest EC50 value (100.10 µg/ml). The result indicated that the antioxidant activity was not correlated with the phenolics content suggested that non-phenolic compounds might play major free radicals scavenging activity in studied plant materials

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