Synergistic action of starch and honey against Pseudomonas aeruginosa in correlation with diastase number

To evaluate the synergistic action of starch on the antibacterial activity of honey against Pseudomonas aeruginosa, a comparative method of adding honey with and without starch to culture media was used. P. aeruginosa (ATCC 27853) was used to determine the minimum inhibitory concentration (MIC) of five varieties of honey. In a second step, lower concentrations of honey than the MIC were incubated with a set of concentrations of starch and then added to media to determine the minimum synergistic inhibitory concentration. The MIC for the five varieties of honey without starch against P. aeruginosa ranged between 15% and 26% (vol/vol). When starch was incubated with honey and then added to media, a significant MIC drop has been noticed with each variety and it ranged between 30.7% and 46.6%. No significant correlation has been established between the MIC drop and the diastase number.