Antimicrobial activity and phytochemical screening of serial extracts from leaves of Aegle marmelos (Linn.)

Abstract

The in vitro antimicrobial activity of serial petroleum ether, chloroform and methanol extracts from leaves of Aegle marmelos were investigated against bacterial and fungal species. All the extracts exhibited broad spectrum antimicrobial activity with zones of inhibition ranging from 10 to 22 mm against bacteria: Staphylococcus aureus, β Streptococcus haemolyticus group A, Proteus mirabilis, Klebsiella pneumoniae, Pseudomonas aeruginosa, Escherichia coli, Salmonella typhi, fungi: Candida albicans, Candida tropicalis and Aspergillus flavus. The minimal inhibitory concentrations (MIC) and the minimal microbicidal concentrations (MMC) of the extracts ranged from 1.25 to 10 mg/mL and 2.5 to 20 mg/mL respectively. Assessment of antibacterial efficacy of different extract revealed that Staphylococcus aureus, β Streptococcus haemolyticus group A, Pseudomonas aeruginosa and Escherichia coli showed high susceptibility to petroleum ether extract. Proteus mirabilis, Klebsiella pneumoniae showed high susceptibility to chloroform extract and Salmonella typhi showed high susceptibility to methanol extract. Petroleum ether extract exhibited the highest antifungal efficacy against all tested fungal species. Phytochemical screening revealed the presence of phenols, sterols in petroleum ether and chloroform extracts, whereas tannins, flavonoids, coumarins, saponins and triterpenoids in methanol extract. The ability of the leaf extracts of Aegle marmelos to inhibit growth of bacteria and fungi is an indication of its broad spectrum antimicrobial activity which could be a potential source for development of novel bioactive antimicrobial agents.