Antibacterial activity of Anacardium occidentale Linn (Cashew) nut shell extract against some clinical bacterial isolates
Simeon Chukwuemeka Enemuor*, Paul Osinachi Amaje and Christian Kelechi Ezeh
Biocatalysis and Environmental Health Research Group
Department of Microbiology, Faculty of Biological Sciences, University of Nigeria, Nsukka, Enugu State, Nigeria.
| Key words:
Anacardium occidentale, Antibacterial activity, Cashew, extract.
*Corresponding author: simeon.enemuor@unn.edu.ng,
Page No: 38-44 |
AbstractCashew nut shell extracts were prepared using methanol and ethanol as the extracting solvents. The extracts were subject to phytochemical analysis. The antibacterial activity of the extracts on four human pathogens of clinical importance, Escherichia coli, Salmonella typhi, Staphylococcus aureus and Bacillus subtitlis were investigated using the agar well diffusion and tube dilution methods. The phytochemical analysis revealed the presence of terpenoids, tannins, flavonoids and phenolics. All test organisms were sensitive to the extracts, although there were differences in their zones of inhibition. In terms of sensitivity, Escherichia coli, Salmonella typhi and Staphylococcus aureus were sensitive to methanol extract at 5 mg/ml but Bacillus substilis was sensitive at 10 mg/ml. All test organisms were sensitive to ethanol extract at 5 mg/ml. Ethanolic extract was more potent compared to methanol extracts. Ethanol extract had the Minimum Inhibitory Concentration (MIC) of 25 mg/ml on Escherichia coli and Salmonella typhi. The results showed that ethanol extracted more antibacterial compounds than methanol from cashew nut shell. From the finding, extracts from cashew nut shell showed promising pharmaceutical values for fighting human pathogens. |