EFFECT OF TRIGONA HONEY ON Escherichia Coli CELL CULTURE GROWTH: IN VITRO STUDY

Honey is considered to be the emerging antibacterial agent that may take over the role of antibiotics in future. Effectiveness of Trigona honey was assessed against E. colicell culture growth using brain heart infusion medium. The antimicrobial activity was examined by agar well diffusion assays, minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC), time-kill curve and biofilm formation in 96-well plates. Planktonic cells were cultivated in microtiter plates with varying concentrations of honey (10%, 20%, 30%, 40% and 50% w/v) for specific incubation time (24, 48, and 72 hours) at 37oC. The extent of cell growth was estimated by staining with crystal violet dye and taking measurements at 570nm. Agar diffusion assay showed thatTrigona honey to possess highest total antibacterial activity against E.coli, 18.2±0.6 mm, 17.2±0.4 mm, 15.2±0.3 mm, 13.5±0.4 mm, 9.0±0.2 mm at concentration 50%, 40%, 30%, 20% and 10% of honeyrespectively. The MIC value against E.coliwas 10% (w/v) and MBC was 30% (w/v). In time-kill curve Trigona honey was inhibited E.coli in a 4 log10 at 18 hours, and total viable counts (TVCs) were killed after 24 hours. It was found that even ≥30% Trigona honey dilution interfered significantly with E. coli cell culture growth. Moreover it was found that a difference of more than 10% honey concentration between the treatments was considered significant to produce inhibitory effects. This study has shown that Trigona honey has significant inhibitory effects on E. coli growth in vitro. Trigona honey may be used as an alternative to antibiotics in controlling infections caused by E. coli. However further investigation is required to strengthen this argument. Keywords: Trigona honey, Escherichia coli,Inhibitory effects,Minimum Inhibitory Concentration (MIC), Minimum Bactericidal Concentration, Time Kill Curve