Anti-fungal and antioxidant properties of propolis (bee glue) extracts

Abstract

This study aimed to identify the phenolic compounds contained in propolis and to evaluate the effect of propolis and its extracts on the antifungal activity, pH, color, and sensory analysis of creamy cheese with thyme (thyme labneh). Ethanolic and water extracts of propolis were evaluated to determine its phenolic compound content and antioxidant activity. Phenolic compounds in propolis were identified and quantified using gas chromatography–mass spectrometry (GC–MS). Antifungal activities, color, pH, and sensory evaluation of propolis and its extracts (water and ethanolic) were investigated at concentrations of 0.5%, 1%, and 1.5%. The results showed 11 phenolic compounds in the propolis extract. Our findings revealed a significant difference in phenolic content and antioxidant activity in the ethanolic extract of propolis when compared with the water extract (P < 0.05). Microbial counts in thyme labneh treated with propolis powder and its extracts (ethanolic and water) showed significant differences compared with the control at all concentrations (0.5%, 1%, and 1.5%). Propolis powder and ethanolic extracts at concentrations of 1% and 1.5% were limited the rapid growth of mold and yeast, so the results showed no significant difference between 14 and 21 days for these samples. In addition, the 1.5% water extract did not show a significant difference (P > 0.05) between Days 14 and 21. The sensory panel did not detect a significant difference in any sensory attribute in the thyme labneh treated with propolis extracts. This study identified the significant antioxidant and antimicrobial effectiveness of using propolis in dairy products, suggesting its potential as a natural preservative.