Determination and Comparison of Phenolic Compound Content and Antimicrobial Activity of Some Propolis Samples in Turkey

Abstract

Objective: Ethanol extraction is the most popular technique for the production of propolis extracts. However, this method may not be suitable for various clinical conditions. Based on it, we composed a trial product with an olive-oil extraction as an alternative method. Furthermore, we crafted combinations to reinforce and synergize the antimicrobial activity of the trial propolis product. Finally, we compared our trial products with the existing marketing products in Turkey. The present study aimed to determine chemical compounds and the antimicrobial activity of some propolis samples selected from Turkey and compare the mentioned features with the olive-oil- trial products we composed for the study.
 Material-Methods: Four different samples, as trial and final products, were crafted for the study. Trail products conducted as sample 1 to 4 (S1, S2, S3 and S4). The trial products were compared with the four other propolis and propolis-containing combined products currently exciting on the market. Four different trademarks were used, and the Trademarks (TM) was called TM1, TM2 TM3, and TM4. Determination of Total Phenolic Compound (TPC) was analyzed according to the Folin-Ciocalteau method. The antimicrobial activity test was determined according to the Kirby-Bauer method.
 Results: The highest TPC ratio was detected in the trademark 2 (TM2), and the lowest TPC ratio was determined in the TM4 samples, 19553.12 GAE mg/L and 740.9 GAE mg/L, respectively. The TPC ratio of the final trial product sample 4 (S4) was defined as 6519.3 GAE mg/L. The highest inhibitation zone against E. coli, K. pneumoniae, S. aureus strains was observed in S1 (the oleuropein-containing trial product). The highest inhabitation zone against C. albicans and C. krusei yeasts was observed in TM1 and S4 (the oleuropein and boron-containing trial propolis product) samples. 
 Conclusion: The S4 product, containing boron, oleuropein, and propolis, had a higher inhibitation zone diameters compared to the commercial brands. Furthermore, all the propolis products analyzed in this study had rich phenolic components; the curative and beneficial impacts of phenolic components on health merit further investigations.