Antimicrobial activity of Averrhoa carambola L. leaf extract and its Phytochemical Analysis

Growing drug resistance of microorganisms and adverse result of antibiotic usage have led to the search for alternative medicines from nature. Many plants have been exploited to cure infectious diseases from time immemorial. The current investigation deals with the evaluation of the antimicrobial activity, preliminary phytochemical screening and Thin Layer Chromatography (TLC) analysis of Averrhoa carambola L. leaf extracts. The antimicrobial activity was done by agar well diffusion method. Preliminary phytochemical screening was done by standard method. Plant extracts were found active against all the bacteria. Aqueous extract of A. carambola leaves showed higher antibacterial activity as compared with methanol and petroleum ether extract at the concentration of 25 mg/ml. Highest antibacterial activity was exhibited by the aqueous extract against Salmonella typhi (29.23±0.02 mm). The highest antifungal potential was exhibited by the methanol extract against Candida krusei (21.09±0.08 mm). Plant extracts were observed to be active against all the fungal pathogens except Aspergillus niger. Minimum inhibitory concentration (MIC) was determined using serial dilution method. The preliminary phytochemical analysis revealed the presence of alkaloids, tannins and polyphenolic compounds, flavonoids, phytosterol, proteins and amino acids, carbohydrates, glycosides etc. while saponins was absent in both the extract. The petroleum ether and methanolic extracts were subjected to TLC study and the Rf value of different spots was observed in various solvent systems. The outcomes of the present study indicate that A. carambola leaf is endowed with potential antimicrobial activity and hold promise for development of pharmaceuticals and antimicrobial agents in future.