PHYTOCHEMICAL SCREENING AND ANTI-OXIDANT POTENTIAL OF EXTRACTS OF SOLANUM NIGRUM

Abstract

Solanum nigrum also known as makoy plant or Black nightshade, is a commonly used herb with ethnomedicinal importance. It is a Eurasian species, widely distributed in Middle East, India, Africa. The plant is a constituent of several Indian medicines useful in relief of number of health conditions like fever, stomach issues, dysentery, ulcers, asthma, jaundice and whooping cough. It is said to have many therapeutic activities including antitumor, antioxidant, anti-inflammatory, hepatoprotective, diuretic, antipyretic activities. The present study includes evaluation of phytochemical constituents, and in vitro antioxidant activities of extracts of Solanum nigrum leaves with the aim to furnish more information on its therapeutic potential. Extraction of the

dried leaves of Solanum nigrum was carried in 70% ethanol followed by partitioning in, n- haxane, Dichloromethane (DCM), ethyl acetate and methanol. Preliminary phytochemical

screening of the extracts and all the fractions was carried out as per the standard methods. Antioxidant study of the fractions was carried out by DPPH scavenging assay, nitric oxide scavenging assay and by determination of reducing power. Phytochemical screening of all the extracts and fractions revealed that n-hexane and DCM fractions contained maximum secondary metabolites including alkaloids, glycosides, saponins, phenolic compounds and coumarin. The extract was found to possess potent antioxidant activity which was found to be comparable to standard antioxidant compounds. Reducing power of hexane and DCM fractions was found to increase with increase in concentration and was comparable to ascorbic acid. The fractions also scavenged the DPPH radical due to antioxidant potential. The IC50 value of quercetin, hexane and DCM fraction was found to be 0.477±0.002, 44.067±0.001 and 62.569±0.002 respectively. The two fractions also found to scavenge nitric oxide similar to ascorbic acid and the antioxidant capacity was observed to increase with increasing concentration. IC50 value of ascorbic acid, hexane and DCM fraction was found to be 116.127±0.003, 217.833±0.002 and 226.487±0.003 respectively. This study forms basis for future research activities on extracts and active compounds of Solanum nigrum.