Comparative phytochemical screening and in-vitro antioxidant assay of aqueous and ethanolic extract of Phyllanthus amarus leaves

This study was carried out to evaluate the phytochemical constituents and antioxidant potentials of the aqueous and ethanolic leaf extracts of Phyllanthus amarus. Phytochemical constituents were determined using standard procedures. The antioxidant potentials of both extracts were evaluated using 2, 2-diphenyl-1-picrylhydrazyl (DPPH) Scavenging assay, reducing power activity by the method described by  Oyaizu (Fe3 - Fe2+ and measuring of Perl’s Prussian blue complex) and total antioxidant capacity by phosphomolybdenum method (Prieto). Total phenol, flavonoid, saponin and tannin were evaluated by Folin-Ciocalteu, Aluminum chloride (Olajire), Vanillin-Sulphuric acid and Broad Hurst method respectively. In the DPPH scavenging assay, the IC50 values of ethanolic and aqueous extract were 5.36, and 0.21 mg/ml and the standard reference IC50 value for Gallic acid was 5.26mg/ml. Total antioxidant capacity of the aqueous and ethanolic extracts was 0.71mg/ml equivalent of ascorbic acid and 0.8mg/ml equivalent of ascorbic acid at higher concentration (4mg/ml). The ethanolic and aqueous extract exhibited a similar pattern of reducing power activity, slightly different from that of Ascorbic acid. However, in all three cases, the reduction was linear. Total phenolic content of ethanolic and aqueous extract yielded 0.40±0.01mg GAE/g extract and 0.39±0.09mg GAE/g extract. Total flavonoids content of ethanolic and aqueous extract gave 2.6±0.15µg CEq/g extract and 1.53±0.03µg CEq/g extract. Total Saponins content of the ethanolic and aqueous extract was found to be 1.19±0.02mg and 0.92±0.03mg SEq/g extract. The total tannins content in ethanolic and aqueous extract was found to be 0.13±0.01 and 0.02±0.01mg CEq/g extract. The result obtained showed that aqueous and ethanolic extracts of Phyllanthus amarus leaves demonstrated a substantial amount of biochemically valuable phytochemicals and antioxidant potential.