Because of the tradition of using honey as an antimicrobial medicament, we investigated the effect of natural honey (NH) on Streptococcus mutans growth, viability and biofilm formation compared to an artificial honey (AH).

AH contained the sugars at the concentrations reported for NH. NH and AH concentrations were obtained by serial dilution with tryptic soy broth (TSB). Several concentrations of NH and AH were tested for inhibition of bacterial growth, viability and biofilm formation after inoculation with S. mutans UA159 in 96-well microtiter plates to obtain absorbance and CFU values.

Overall, NH supported significantly less bacterial growth compared to the AH at 25 and 12.5% concentrations. At 50 and 25% concentrations, both honey groups provided significantly less bacterial growth and biofilm formation compared to the TSB control.

For bacterial viability, all honey concentrations were not significantly different from the TSB control except for 50% NH. NH was able to decrease the maximum velocity of S. mutans growth compared to AH.

In summary, NH demonstrated more inhibition of bacterial growth, viability and biofilm compared to AH. This study highlights the potential antibacterial properties of NH, and could suggest that the antimicrobial mechanism of NH is not solely due to its high sugar content.

References

1. ^{^} Appl Environ Microbiol (aem.asm.org)