Antibacterial activity of various honey types of Algeria against Pathogenic Gram–Negative Bacilli: Escherichia coli and Pseudomonas aeruginosa

To assess the in vitro antibacterial activity of different honey types in Algeria on Gram negative organismes. Different concentrations (10, 30, 50, 70, 100 % v/v) of honey were studied in vitro using Escherichia coli (E. coli) and Pseudomonas aeruginosa (P. aeruginosa). Briefly, two-fold dilutions of honey solutions were tested to determine the minimum inhibitory concentration (MIC) against each type of microorganism, followed by more assays within a narrower dilution range to obtain more precise MIC values. MIC was determined by both visual inspection and spectrophotometric assay at 620 nm. The antibacterial activity of these honey samples was determined by the disc and well diffusion method. The zone diameter of inhibition of honey for P. aeruginosa and E. coli was 0–30 and 0–38 mm, respectively, while the MIC ranged 90–91% and 56–96%, respectively. The results show that Algerian honeys possess antibacterial activity against Gram negative bacilli, and it can be developed into antibacterial agents.