Antibacterial Investigation of Saharan Propolis Coating on Conventional Surgical Threads

Background: Conventional surgical threads (CST) are often colonized with drug-resistant polymicrobial biofilms.However, such bioactive agent-incorporated CST are needed to solve this problem.The aim of this study was to develop a coating for CST consisting of the antibacterial Etha-nolic Extract of Sahara Propolis (EESP) as a release topical delivery system for treating wounds, characterize the EESP and study the release profiles and antibacterial activity of EESP-CST against S. aureus and P. aeruginosa. Methods: The chemical profiles of the samples were assessed by X-ray powder diffraction (XRD), Fourier-transform infrared (FT-IR) and 1H and 13C nuclear magnetic resonance (NMR) spectroscopy. The release profiles were measured in Mueller-Hinton broth (MHB) with different time 0, 30, 45, 60, 90min and 24h. Antibacterial activity was carried out through the agar diffusion method in Mueller-Hinton Agar (MHA). Results: According to the FTIR, 1H and 13C NMR analysis, the EESP through its various peaks and the various functional groups were detected. Besides, the propolis powder showed a very low degree of crystalline material (amorphous structure) as observed by X-ray powder diffraction. Exposure to EESP-CST short-term resulted in a significant reduction in absorbance at 90 min of exposure for S. aureus in MHB. In addition, the EESP-CST has not shown any significant reduction in absorbance after on for P. aeruginosa in absorbance at 90 min. However, its antibacterial ability gradually de-creases after 90 min for the two bacteria tested. In MHA the zone of inhibition assay documented a efficacy of EESP-CST against S. aureus over 24 hours. But, adherence of the colony to the surface of EESP-CST was observed for P. aeruginosa. Conclusion: These results supported that the EESP-CST was successful in inhibiting the growth of S. aureus. on short-term in a liquid culture assay. Therefore, EESP-CST as a prevention of wound infections and can be an appropriate candidate for more clinical investigations.