Speaker
Description
Antimicrobial resistance (AMR) remains a major global health challenge, driven largely by multidrug-resistant ESKAPE pathogens (Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Enterobacter spp.). In Ghana, AMR-related infections were associated with an estimated 4.95 million deaths in 2019. With the declining efficacy of conventional antibiotics, antivirulence strategies including quorum sensing (QS) and efflux pump inhibition are gaining attention for their ability to reduce pathogenicity without imposing strong selective pressure for resistance. Salacia debilis, a medicinal shrub traditionally used for malaria treatment, has yielded bioactive compounds with moderate antimicrobial activity: SD-03 (Benzyl 2-methoxybenzoate) and SD-04 (1,10-dihydroxy-6H-benzo[c]chromen-6-one). However, their potential as QS and efflux pump inhibitors has not been explored. This study investigates the QS and efflux pump inhibitory activities of S. debilis extracts. Crude and ethyl acetate extracts inhibited S. aureus and P. aeruginosa growth, with minimum inhibitory concentrations (MICs) of 6.25–25.00 mg/ml. After isolation and characterization of the isolates, 100μg/ml concentration was prepared for each and their antimicrobial activity was tested using broth dilution assay. However, at MIC and sub-MIC doses, both isolates were not able to inhibit the growth of P. aeruginosa and S. aureus. The isolates were assessed for their antivirulence activity using the biofilm inhibitory assay. The isolates were able to eradicate preformed biofilm and inhibit the growth of biofilm formation.These findings suggest that S. debilis derived compounds have antivirulence potential by targeting bacterial communication and drug resistance mechanisms.
Keywords: Salacia debilis; antimicrobial resistance; ESKAPE pathogens; antivirulence; quorum sensing; efflux pump.