Abstract Description

Peltophorum africanum is widely used in indigenous medicine to treat infections, wounds, and inflammatory conditions. This study employs a bioassay-guided approach to isolate antibacterial compounds, evaluating their pharmacological mechanisms and supporting their potential as sources of anti-infective agents. The study aimed to investigate P. africanum stem as a potential source of novel compounds for drug discovery, emphasizing its antibacterial, antibiofilm, and antioxidant properties. Chromatographic techniques were used to fractionate and isolate antibacterial compounds. Structural elucidation was performed using NMR and LC-MS. Antioxidant activity was assessed using the DPPH radical scavenging assay. Antibacterial activity was determined using the microbroth dilution method against Pseudomonas aeruginosa and Staphylococcus aureus. Anti-biofilm activity was evaluated using the crystal violet staining method. The antibacterial mechanism of action of the most active fraction was examined by assessing changes in INT-dehydrogenase activity and monitoring the leakage of intracellular proteins and DNA. Betulinic acid-3-3,4-dihydroxybenzoate and 3-octadecanoyl stigmasterol were isolated from the hexane crude extract. LC-MS identified 13 compounds. The MIC of the compounds was varied against P. aeruginosa and S. aureus was 0.63 and 1.25 mg/mL respectively. Isolated compounds had noteworthy activity across all biofilm phases. The fraction exhibited the lowest number of viable cells when assessing INT-dehydrogenase activity. Additionally, it was more effective in causing the release of intracellular proteins and DNA, while also displaying superior antioxidant activity. The ability of antioxidant and antibacterial compounds of the P. africanum stem to inhibit biofilm formation and eradicate the mature biofilms holds promise for the treatment of biofilm-associated nosocomial infections.