Antimicrobial activity of Propol-5, an ethanolic extract of Cuban propolis

Abstract

Introduction: It is considered that the information on the antimicrobial properties of Propol-5, ethanolic extract of 5% propolis produced at the Center for Immunology and Biopreparates, Holguín, Cuba, is not yet sufficient.

Objective: Demonstrate in vitro the antimicrobial activity of Propol-5 (CIBHO®).

Methods: An experimental research was carried out that included four batches of Propol-5 to determine the minimum inhibitory concentration by the method of microdilution in broth against reference strains and multi-resistant clinical isolates. For the comparison of the results, the Kruskal-Wallis test was used.

Results: Antimicrobial activity was demonstrated against Staphylococcus aureus ATCC 29213 (CMI = 3.12-25 mg/mL); Enterococcus faecalis ATCC 29212 (CMI = 12.5 mg/mL); Escherichia coli ATCC 25922 and Pseudomonas aeruginosa ATCC 27853 (CMI = 6.25-12.5 mg/mL and CMI = 6.25-25 mg/mL, respectively); Candida albicans ATCC 90028 (CMI = 1.56-6.25 mg/mL) and Candida krusei ATCC 6258 (CMI = 3.12-12.5 mg/mL). CMI versus clinical isolates of S. aureus ranged from 3.12-12.5 mg/mL; for P. aeruginosa and Candida spp. was lower, 3.12-6.25 mg/mL and 1.56-6.25 mg/mL, respectively. No significant differences were found between these values (p > 0.05).

Conclusions: The demonstration of the effectiveness of Propol-5 (CIBHO®) to inhibit the growth of yeasts and gram-positive and gram-negative bacteria confirms the antimicrobial activity that was deduced for it from the characterization of other ethanolic extracts of propolis. The fact of having ratified its activity against multi-resistant clinical strains allows, in the face of infections produced by these strains, to propose it as a therapeutic alternative to consider.