In vitro Antimicrobial Activity of Clerodendron Polycephalum Against Clinical Bacterial Isolates

Abstract

Clerodendron polycephalum Baker (known as Ewe Agbosa in Yoruba land) is used by the traditional people in South West Nigeria for arresting bleeding from cuts and treating bacteria infections especially wound infection without scientific proof of its efficacy. This study aimed at investigating the antimicrobial activity of C. polycephalum and to analyse the phytochemical components present. The antimicrobial activity of aqueous and ethanol extracts of the plant were investigated against clinical bacterial isolates using agar diffusion method, the MIC and MBC was determined against S. aureus using two fold dilution of the plant extract and the phytochemical components were determined using standard methods. The plant extracts exhibited broad-spectrum antimicrobial activities, which was more in ethanol extract than aqueous extract. The plant extracts inhibited Staphylococcus aureus, Enterococcus faecalis, Pseudomonas aeruginosa, Proteus mirabilis, Klebsiella pneumoniae and some Escherichia coli that were resistant to more than four antibiotics including Pefloxacin. The best inhibition activity was against S. aureus (26mm) at a concentration of 50 mg/ml. The extract is bacteriostatic at 1.57mg/ml and bactericidal at 3.13mg/ml. The leaves extract of C. polycephalum reduced number of viable cells of S. aureus by 2log unit in 1 hour of incubation, and total killing in 4hours. The antimicrobial properties of the plant can be attributed to the presence of saponins, flavonoides, anthraquinones and tannins in the extracts. The antimicrobial activities exhibited by this medicinal plant justify its use in the treatment of infected wounds.