Investigating the antimicrobial activity of Myrothamnus flabellifolius plant extract against Staphylococcus aureus · Electronic Theses and Dissertations

Author

Mugwenhi, Brian R.

Title

Investigating the antimicrobial activity of Myrothamnus flabellifolius plant extract against Staphylococcus aureus

Abstract

The rapid emerging of specific bacterial types that are resistant to standard antibiotics is causing a global challenge for the effective use of current antimicrobial therapies, enforcing the need for the exploration of alternative novel antimicrobial agents that include traditional plants. It serves as a medicinal herb that is native to Southern Africa, well known for its resilience to extreme weather desiccation and its traditional uses in treating infections and inflammatory conditions. This research study is based on analysis of antimicrobial potentials of M. flabellifolius leaf plant extracts against S. aureus. The main aims were to identify and characterize the phytochemicals found in the plant’s leaves, use of disk diffusion method to assess the antimicrobial effectiveness of the extracts, finding the minimum concentrations that inhibit or kill bacteria. Preliminary chemical-based screening of bioactive compounds showed the presents of phytochemicals which include flavonoids, tannins, phenolics as well as terpenoids. Solvent extraction techniques were done whereby methanol was the best extraction solvent with extraction mean yield percentages of 14.0, 13.4 and 11.8. Ethanol had mean extraction yield percentages of 8.5, 6.0 and 1.16 whilst aqueous obtained 5.0. Methanolic extract had the most antibacterial activity against S. aureus shown at all concentrations (12.5mg/ml, 25mg/ml, 50mg/ml, 100mg/ml). At 100mg/ml mean ZOI for methanol was 20.0mm, ethanol had 17.0mm and 13.0mm for aqueous. Methanol extract had MIC of 25mg/ml, ethanol extract had 50mg/ml and aqueous extract had 100mg/ml. Methanol extract had 50mg/ml MBC, ethanol extract had 100mg/ml and aqueous extract was not bactericidal. Alamycin and pure distilled water were involved as controls for positive and negative tests. Data analysis of the results has revealed the effectiveness of the extracts by showing p value(s) of 0.000 that is below the alpha significance level of 0.005. Hence these findings showed that M. flabellifolius has antimicrobial activity against S. aureus and holds a potential future as a natural novel agent of antibiotics, particularly against gram positive bacteria.

Date

June 2025

Publisher

BUSE

Keywords

antimicrobial therapies

traditional plants

bacterial types

Supervisor

Mr. P Munosiyei