In-vitro Antibacterial Activity of the Aqueous and Ethanolic Leaf Extracts of Alchornea cordifolia against Isolates from Throat Swabs, Ear Swabs and Sputum Samples

Many bacteria species have been reported to develop resistance to antibiotics commonly prescribed for respiratory tract infections. This study aims to search for natural products for remedy of this problem and also to validate the claim by locals in the use of Achornea cordifolia in the treatment of respiratory tract infections. Isolation and identification of bacteria isolates were carried out using standard microbiological methods and MicroGen identification kits. . Cold maceration extraction method was employed for the extraction of ethanol and aqueous extracts of Alchornea cordifolia leaves. Agar well diffusion and agar dilution methods were employed to determine the zone of inhibition, minimum inhibitory concentration and minimum bactericidal concentration of the extracts respectively. The result showed that out of 180 samples from throat (68), ear swabs (57) and sputum (55) collected from patients with respiratory tract infection in Ahmadu Bello University Teaching Hospital Zaria, Nigeria, 208 isolates were obtained. Seventeen (17) bacteria species were identified as; Staphylococcus aureus (7), Streptococcus spp. (5), Pseudomonas aeruginosa (2), Klebsiella pneumoniae (2), and Escherichia coli (1). The two extracts showed broad spectrum activity but the aqueous extract had larger zones of inhibition ranging from 11.5mm - 32. 5mm and lower M.I.C and M.B.C values ranging from 5 mg/ml – 20 mg/ml. The aqueous and ethanol leaf extracts of Alchornea cordifolia was found to possess antibacterial activity against isolates from patients with respiratory tract infection in Ahmadu Bello University Teaching Hospital Zaria, Nigeria.