Background: The study investigated activity of honey towards pathogens when grown in media contained honey, or when honey was added to cultures after inoculation.
Material/methods: 1--Staphylococcus aureus (S. aureus), Streptococcus pyogenes (S. pyogenes), E.coli and Candida albicans (C. albicans) were cultured into broth containing 10-100% (wt/v) honey concentrations. 2--Honey was added to broth inoculated with isolates after inoculation. 3--Optimum growth of isolates, therapeutic period of honey, and time after addition of honey that showed optimum effect was measured.
Results: The optimum growth of E. Coli and C. Albicans was 10 hrs and S. aureus was 12 hrs. Honey (30-70%) prevents growth of all isolates. Honey (80%) inhibited growth of small (1 microl) and large size of inoculum (10 microl) of E. Coli and S. Aureus when added to their cultures during 24 hrs after inoculation. Honey inhibited growth of C. Albicans when added during 2 to 6 hrs after inoculation. Honey delayed the appearance of microbial growth on the plates. Reculturing of specimens collected from media that showed no growth after addition of honey yielded recovery growth for E.coli and C. Albicans, and therapeutic period of honey for E.coli and S. Aureus was 2-24 hrs and for C. Albicans was 2-6 hrs.
Conclusions: Honey prevents growth of the isolates and inhibits their growth when honey was added to growing culture. The therapeutic period of honey and recovery growth of inhibited isolates necessitates adjustment of honey doses according to type of isolate and grade of growth.