In vitro Antioxidant and Antimicrobial Activity of Ethanolic Extract of Egg Plant (Solanum melongena Linn) Fruit

Abstract

Ethnomedicinal use of plant has been effective in the amelioration of oxidative stress and in the inhibition of pathogenic microorganism. The ethanolic extract of Solanum melongena Linn fruit as a potent in vitro antioxidant and antimicrobial agent was investigated using standard protocols. The results showed that the ethanolic extract of Solanum melongena Linn fruit scavenged 1, 1-diphenyl-2-picrylhydrazyl (DPPH) and nitric oxide (NO.), and inhibited lipid peroxidation (LPO) compared to standard (vitamin C). It also reduced ferric ion (as measured through ferric reducing antioxidant potential (FRAP)) compared to the standard, ethylenediaminetetraacetic acid (EDTA). The observed in vitro antioxidant activity of the sample was dose dependent. At a minimum inhibition concentration (MIC) of 50 µg/ml, the ethanolic extract of Solanum melongena Linn fruit showed the highest activity against the bacterium, Staphylococcus auerus (16.33 ± 2.69mm) and the fungi, Aspergillus flavus (3.33 ± 0.38mm at 70.00 µg/ml). The bacteria, Eschericha coli and Salmonella typhi and the fungus, Rhizopus stolonifer were not susceptible to the ethanolic extract at the tested concentrations. The ethanolic extract at 10.00 µg/ml and 30.00 µg/ml could not inhibit any of the studied pathogens. In conclusion, the ethanolic extract of Solanum melongena Linn fruit exhibited a varied degree of appreciable in vitro antioxidant activities compared with the tested methods and standard. Its activity against the tested bacterial and fungal strains underscores its apparent pharmacological potential, warranting further studies.