Abstract:
Infection due to multidrug resistance pathogens is difficult to manage due to
bacterial virulence factors and because of a relatively limited choice of antimicrobial
agents. Thus, it is imperative to discover fresh antimicrobials or new practices that are
effective for the treatment of infectious diseases caused by drug-resistant microorganisms.
The objective of this experiment is to investigate for synergistic outcomes when crude
methanolic extract of the stem bark of Afzelia africana and antibiotics were combined
against a panel of antibiotic resistant bacterial strains that have been implicated in
infections. Standard microbiological protocols were used to determine the minimum
inhibitory concentrations (MICs) of the extract and antibiotics, as well as to investigate the
effect of combinations of the methanolic extract of A. africana stem bark and selected
antibiotics using the time-kill assay method. The extract of Afzelia africana exhibited
antibacterial activities against both Gram-negative and Gram-positive bacteria made up of environmental and standard strains at a screening concentration of 5 mg/mL. The MICs of
the crude extracts and the antibiotics varied between 1 μg/mL and 5.0 mg/mL. Overall,
synergistic response constituted about 63.79% of all manner of combinations of extract and
antibiotics against all test organisms; antagonism was not detected among the 176 tests
carried out. The extract from A. africana stem bark showed potentials of synergy in
combination with antibiotics against strains of pathogenic bacteria. The detection of
synergy between the extract and antibiotics demonstrates the potential of this plant as a
source of antibiotic resistance modulating compounds.
