GC-MS profiling, Beta-lactamase Inhibition Assay, and Molecular Docking Studies on Selected Medicinal Plants

Bacterial infections are continually developing resistance to conventional antibiotic agents, thereby prompting the search for bioactive compounds from plant parts that would serve as lead molecules in the discovery and development of new drugs. There is a need to explore sustainable, innovative, and safe natural therapeutic methods in preventing and managing AMR infections. Beta-lactamase secretion by bacteria is one of the main resistant mechanisms bacterial enzymes use to resist antibiotics. Hence, this study investigated the beta-lactamase inhibition potential of Salacia nitida and Rauvolfia vomitoria root extracts. Gas chromatography-mass spectrometry (GC-MS) analysis was carried out on the root extracts of S. nitida and R. vomitoria. Molecular docking was performed to determine the binding affinity and energy between class A beta-lactamase and selected bioactive compounds. Results from the beta-lactamase inhibition assay showed that S. nitida and R. vomitoria root extracts had 65.87% and 69.89% inhibitory activity, respectively, against the beta-lactamase enzyme, suggesting that these plant extracts have the potential to be used as a beta-lactamase inhibitor in combination with beta-lactam antibiotics. The GC-MS results revealed 10 bioactive compounds in S. nitida and 28 compounds in R. vomitoria. Molecular docking results showed favourable hydrogen bonds and Van der waal interactions between beta-lactamase and selected bioactive compounds. The findings suggest that these plant extracts possess significant beta-lactamase inhibition activity and this can further lend pharmacological support to their folklore uses as antibiotic agents.