Phytochemical and antibacterial properties of Acalypha hispida leaves
The active ingredients in the leaves of Acalypha hispida plant were extracted with ethanol, methanol, chloroform and water to ascertain the extractive potentials of the solvents and the antibacterial properties of the extracts. The organisms used for the antibacterial properties assessment were E. coli, Staphylococcus aureus, Pseudomonas aeruginosa and Salmonella typhi. The susceptibilities of the test bacteria to the extracts were determined using the minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC) and zone of inhibition test (ZIT) methods. The test organisms were susceptible to the extracts, although this varied across different solvent extracts and the test bacteria. The Methanol extract exhibited more antibacterial activity against the test bacteria, followed by ethanol, chloroform and water in decreasing order. There was no significant difference between the antibacterial effect of methanol and ethanol extracts of A. hispida on P. aeruginosa and E. coli (p>0.05). There was however significant difference between the antibacterial effect of methanol and ethanol extracts of A. hispida on S. aureus and S. typhi (p<0.05). The extractive potentials of the solvents were in the order; methanol > ethanol > chloroform > water. Phytochemical screening of the leaf extracts revealed the presence of tannin, alkaloid, steroid, saponin and flavonoid, while hydrogen cyanide and carbohydrate were absent.
Key words: Acalypha hispida, bacteria, antibacterial activity and phytochemical properties