Antioxidant activity, phenolic and flavonoid contents of some wild medicinal plants in southeastern Algeria

This study reported on five plants known for their use in traditional medicine in southeastern Algeria, namely: Artemisia campestris, Asteriscus pygmaeus, Pituranthos chlorantus, Pallenis spinosa and Aizoon hispanicum. The work aimed to determine the antioxidant activity, phenol and flavonoid contents of their aqueous and methanolic extracts. Flavonoids and phenol contents varied according to the nature of the extract and the nature of the plant. Total phenols varied from 30.33 ± 2.03 μg EAG/mg of plant in aqueous extract of Aizoon hispanicum to 280 ± 5.46 μg EAG/mg plant extract in methanolic extract of A. campestris. Flavonoid contents were between 0.071 ± 0.0008 μg QE/mg extract in A. hispanicum aqueous extract and 29.68 ± 0.32 μg QE/mg extract in A. campestris methanolic extract. The aqueous extracts showed the lowest values of flavonoid contents while the methanol extracts showed the highest ones. The antioxidant activities expressed as IC50 values varied from 8.66±1.52 μg/ml for Artemisia aqueous extract, the most active to 325.7±5.50 μg/mL of DPPH solution to the less active Aizoon aqueous extract. The radical scavenging activity decreased in the following order: A. campestris > P. spinosa> P. chlorantus > A. pygmaeus > A. hispanicum. Key words: Antioxidant, flavonoids, phenols, plants.