Comparing Antimicrobial Effects of Heterotrigona itama Propolis from Two Regions of Malaysia Against Enterococcus faecalis

Abstract

Objective: This present study aimed to determine and compare the antimicrobial properties of Malaysian propolis (MP) produced by Heterotrigona Itama from different regions of Malaysia, against E. faecalis. Methods: The propolis were obtained in Lenggong MLP (North Peninsula Malaysia) and Raub MRP - (Central Peninsula Malaysia). The antibacterial activities of the ethanolic extracts of propolis were conducted using antimicrobial susceptibility test (AST), minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC). The effect of these extracts on the cell morphology were observed using scanning electron microscopy (SEM). Calcium hydroxide and 5% dimethyl sulfoxide (DMSO) were used as controls. Results: Statistical analysis was done using unpaired t-test to differentiate the difference of the two averages. The ethanol extracts of MLP showed higher activity compared to MRP at 50mg/ml on E. faecalis with zone of inhibition of 14.33mm and 10.00mm respectively. MIC test for MRP and MLP was 0.78125mg/ml and 3.125mg/ml respectively. Whereas the MBC value for both MRP and MLP was 12.50mg/ml and 50.00mg/ml respectively. SEM analysis showed that MP disrupted the size, cell morphology and the structure of the bacteria cell wall. Conclusion: Our study showed MRP outperformed MLP against E. faecalis via MIC, MBC and SEM. Dissimilarities of surrounding trees in Raub and Lenggong may provide the variable chemical source contributing to this contrast. Thus, these stingless bees have a very special relationship with plant resins, relying on them for the very survival of their nests.