Evaluation of the Antibacterial Activity of Methanol and Chloroform Extracts of Alchornea cordifolia Leaves

Aims: To evaluate the antibacterial activity of the Methanol and Chloroform extracts of the leaves of Alchornea cordifolia and verify the claim that it is used to treat bacterial infections.
Study Design: This is an experimental study involving the extraction of the bioactive agents from Alchornea cordifolia leaf using methanol and chloroform, susceptibility tests (Zones of inhibition) and determination of the Minimum Inhibitory Concentration.
Place and Duration of Study: Study was carried out in Faculty of Pharmaceutical Sciences of Nnamdi Azikiwe University, Agulu Campus between March and June 2012.
Methodology: The leaves of the plant were harvested, dried at room temperature for two weeks and then pulverized. The leaves were divided into two parts of 200mg each. One part was soaked in 500 ml methanol and the other part in 500 ml chloroform (all for 72 hours) to extract the active principles. The extracts were exposed to air to allow the solvents to evaporate completely. The antibacterial activities of the residue against four pathogenic microorganisms (Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa, and Salmonella typhi) were evaluated using agar diffusion and broth dilution techniques in accordance with Clinical Laboratory Standards Institute.
Results: The result showed that the methanol extract has antibacterial activity against the pathogens tested at concentrations 50 mg/ml and above while the chloroform extracts had activity against the micro organisms tested at 200 mg/ml concentration only.
Conclusion: The methanol extract of Alchornea cordifolia leaves has a more potent antibacterial activity than the chloroform extract. The leaves of Alchornea cordifolia can actually be used in the treatment of infection caused by these organisms aforementioned.