Biological Investigations of Dried Fruit of Solanum nigrum Linn.

The ethanolic extract of the dried fruit of Solanum nigrum Linn. (Family: Solanaceae) was assessed for its possible analgesic, antidiarrhoeal, antimicrobial, antioxidant and cytotoxic activity. Phytochemical screening of the ethanolic extract revealed the presence of carbohydrate, alkaloids, tannins, saponins, steroids, glycosides, and gums. In acetic acid induced writhing in mice, the ethanolic extract (250 and 500mg/kg) exhibited significant (p<0.05 & p<0.01) inhibition of writhing reflex 51.39% and 66.67% respectively compared to standard diclofenac sodium. The fruit extract showed a significant (P<0.01 and P<0.001) antidiarrhoeal activity against castor oil induce diarrhoea in mice in which it decreased the frequency of defecation and increased the mean latent period at the dose of 250mg/kg and 500mg/kg body weight. The ethanolic extract showed moderate antibacterial activity against both gram-positive and gram-negative bacteria. In the qualitative antioxidant assay using DPPH (1, 1-diphenyl-2-picryl hydrazyl) the extract showed free radical scavenging properties. In the brine shrimp lethality test, the extract showed cytotoxicity significantly with LC 50 = 63.10μg/ml and LC 90 = 160μg/ml. All the results tend to justify the traditional uses of the plant and require further investigation to identify the chemicals responsible for these effects. Key words: Solanum nigrum Linn; analgesic activity; antidiarrheal activity; antimicrobial activity; antioxidant activity; cytotoxic activity. DOI: 10.3329/sjps.v3i1.6796 S. J. Pharm. Sci. 3(1): 38-45