Evaluation of the Potential Effect of Postbiotics Obtained from Honey Bees against and Their Combination with Other Organic Products.

The mite infests colonies and causes significant harm. Traditional treatments have become less effective because of mite resistance development and can also generate residues inside beehives. This study aimed to gauge the efficacy of a beehive-derived postbiotic in reducing viability and to explore its synergies with organic compounds. Four lactic acid bacteria (LAB) species, , , , and , were isolated and tested in a postbiotic form (preparations of inanimate microorganisms and/or their components) via bioassays. , , and notably reduced the mite viability compared to the control, and they were further tested together as a single postbiotic product (POS). Further bioassays were performed to assess the impact of the POS and its combinations with oxalic acid and oregano essential oil. The simple products and combinations (POS/Oregano, POS/Oxalic, Oregano/Oxalic, and POS/Oregano/Oxalic) decreased the mite viability. The most effective were the oxalic acid combinations (POS/Oregano/Oxalic, Oxalic/Oregano, POS/Oxalic), showing significant improvements compared to the individual products. These findings highlight the potential of combining organic products as a vital strategy for controlling infection. This study suggests that these combinations could serve as essential tools for combating the impact of mites on bee colonies.