Phytochemical characterization and evaluation of antioxidant activity of Populus alba l. in Algeria

The objective of the present study is to evaluate the antioxidant activity in vitro and the phytochemical study of the aqueous extract of the leaves of Populus alba. The phytochemical screening and determination of total phenolic, flavonoid contents and tannins of the leaves extract were carried out. The antioxidant potential was also established by the free radical scavenging (DPPH)and the iron reducing power (FRAP) assays. The tested extract showed their richness in phenolic compounds, terpenoids, steroids and essential oils. Thetotal phenolic contents of plant estimated by Folin-Ciocalteu method were456.11±3.87 mg Equivalent of gallic acid per gof lyophilized extract. Behind, The amount of total flavonoids was 244.5±1.57 mg Equivalent of quercetinper g of lyophilized extract. The assay by the vanillin method revealed that the concentration of condensed tannins was 261.88±4.12 mg Equivalent of catechin per g of lyophilized extract. The in vitro study of the antioxidant activity of the aqueous extract by the free radical scavenging assay free DPPH and the reducing power of iron presented IC50s of the order of: 43.99±0.54 and 86.78±2.15 µg/mL, respectively with comparison with as standard reference (BHT, BHA, Trolox). These results showed that the aqueous extract of the leaves of Populus alba is rich in bioactive substances and characterized by antioxidant power with very promising therapeutic values for the treatment of diseases.