Antimicrobial efficacy of chitosan-Tridax procumbens extract composite on selected wound surface microorganisms

Abstract Background Antimicrobial resistance is a serious health problem that can be associated with wound surface microorganisms and delayed healing in wounds exposed to such microbes. This has led to the exploration of natural compounds with antimicrobial properties to alleviate these difficult situations. This study evaluated the antimicrobial effects of ethanol extract of Tridax procumbens, chitosan, and their composite on some wound surface-associated microorganisms; E. coli, S. aureus, P. aeruginosa, K. pneumoniae, A. niger, M. canis, and C. acremonium. Methods The phytochemical and antioxidant screening were conducted using standard methods. The sensitivity and susceptibility tests were determined using the agar well diffusion and double serial dilution methods respectively. Result The quantitative phytochemical constituents of the extract include phenols, flavonoids, saponins, alkaloids, and tannins. However, the concentration of phenols was significantly (p < 0.05) higher than other phytoconstituents. The ethanol extract of Tridax procumbens-chitosan composite showed a significantly (p < 0.05) higher zone of inhibition against all the tested microorganisms (bacteria and fungi). The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of the composite that limited the growth and completely killed the selected bacteria were observed at 12.5 mg/ml and 25 mg/ml concentrations respectively. while the minimum inhibitory concentration (MIC) and the minimum fungicidal concentration (MFC) of the composite for M. canis and C. acremonium were 12.5 mg/ml and 50 mg/ml whereas, that of A. niger were 6.25 mg/ml and 12 mg/ml respectively. Conclusion The study suggests that ethanol extract of T. tridax procumbens-chitosan composite is more effective as an antimicrobial agent in combating wound surface-associated microbial organisms than the plant extract and chitosan being a single agent.