Susceptibility Patterns of Staphylococcus aureus Isolated from Wounds Swabs to Extracts of Vernonia amygdalina

Abstract

Aims: There is an ever growing interest in investigating different groups of plants to identify their potential therapeutic applications. This is due to a tremendous historical legacy in folk medicine use of plants as remedy for treating diseases. Vernonia amygdalina have been shown to exhibit profound ethnomedical and pharmacological properties. The present study investigated the susceptibility patterns of Staphylococcus aureus isolated from wound infections to extracts of Vernonia amygdalina. Study Design: This study was designed to investigate the susceptibility patterns of Staphylococcus aureus isolated from wound sites of patients attending four hospitals in Akure to extracts of Vernonia amygdalina. Place and Duration of Study: This research was carried out in the Department of Microbiology Federal University of Technology Akure, between November 2015 and April 2016. Methodology: Fresh leaves of Vernonia amygdalina were collected between November 2015 and January 2016 from a farm in Akure and identified at the Department of Crop, Soil and Pest Management, Federal University Technology, Akure (FUTA). The leaf extraction was carried out using four solvents (60% ethanol, cold water, hot water and chloroform). Agar well diffusion technique was used for susceptibility testing of isolates. Results: The phytochemical screening of the extracts revealed various constituents which includes: flavonoids, alkaloids, terpenoids, phenols, cardiac glycoside, saponins and tannins. The ethanol extract showed the lowest Minimum Inhibitory Concentration value (12.5 mg/ml), while the chloroform extract showed the lowest zone of inhibition (10.33 mm) against the S. aureus isolates at 100 mg/ml. The ethanol extract of the plant showed the highest potency against the tested isolates, while the chloroform extract showed the lowest efficacy. Conclusion: The results of this study suggests that Vernonia amygdalina leaf extracts can be used as potential herbs for drug development for the treatment of infections caused by Staphylococcus aureus. This may also help reduce the overdependence on commercial antibiotics and cases of antibiotics resistance.