The inhibitory effect of Ukrainian honey on probiotic bacteria

Honey is used in the food industry as a natural sweetener and has therapeutic effects on the human body. Obtaining quality honey involves using organic preventive and treatment agents in beekeeping. The most common of these agents are probiotic supplements. This research aimed to study honey’s interaction with an inhibitory effect on the growth of microorganisms from the probiotic supplement Immunobacterin-D under laboratory and experimental field conditions. At the first stage of the research, we assessed the effects of ten honey varieties (buckwheat, sunflower, meadow and forest plants, linden) on B. subtilis and B. licheniformis from the dry probiotic supplement. The honey-containing nutrient media had an inhibitory effect on the growth of B. subtilis colonies. After 24 hours of cultivation under aerobic conditions, the concentration of B. subtilis decreased, on average, from 5×1012 colony-forming units in 1 g to 3.2×104 and 2.1×105 CFU/g in samples with monofloral and polyfloral honey, respectively. These results emphasize the need for further research on the symbiotic role of microflora in the stability of the microbiota of the hive and bee colony ecosystem. The next stage of the study investigated the probiotic effect on bee colonies in the field. Observations were made on the sanitary conditions of the hives and the behaviour of bees at the Petrodolyna demo apiary. No differences were found at the macro hive-bee colony ecosystem level between control bee colonies (n = 5) and the experimental ones (n = 5) that had received carbohydrate feeding with added probiotics. This confirms the inhibitory effect of honey on the development of bacteria, which eliminates the risk of uncontrolled growth of B. subtilis and B. licheniformis strain colonies inside the hive and the bacteria getting into bee products. The probiotic had positive effects, increasing the live weight of worker bees by 9.15% by the end of the apiary season compared to the control. This can improve the viability of the bees during wintering. At the last stage of the research, the honey obtained from the experimental colonies was checked for the spores of B. subtilis and B. licheniformis using melissopalynology.