The antimicrobial activities of methanolic extracts of Eucalyptus camalctulensis and Terminalia catappa against some pathogenic microorganisms.

Abstract

Methanolic extracts of leaves of Eucalyptus camaldulensis and Terminalia catappa were studied for in vitro microbial activities by agar dilution method. The phytochemical analysis of the crude extracts of the medicinal plants revealed the presence of saponin, saponin glycosides, steroid, cardiac glycoside, tannins, volatile oils, phenols and balsam (gum). The methanolic extracts of the two plants inhibited the growth of Bacillus subtilis and Staphylococcus aureus (ATCC 103207 and Clinical strain respectively) but had no inhibitory effects on Pseudomonas aeruginosa, Salmonella typhi and Escherichia coli. Candida albicans was inhibited by the crude extracts of E. camaldulensis only. Accelerated gradient chromatography (AGC) gave fractions of the extract of T. catappa that were more active on Candida albicans and Escherichia coli than the crude extract. The minimum inhibitory concentration (MIC) of the extracts ranged from 1.25 g/ml to 5 g/ml. The results obtained suggest that T. catappa and E. camaldulensis can be used in treating diseases caused by the test organisms.