Qualitative phytochemical analysis and in vitro investigation of the immunomodulatory properties of honeys produced in Kazakhstan

Honey is known to have antimicrobial, immunomodulatory and wound healing properties. The biological properties of honey have been attributed to phytochemicals derived from their source plants and research has focused on identifying the bioactive phytochemicals with therapeutic potential. In this study, we determined the ability of 5 honeys from Kazakhstan and manuka honey to stimulate TNF-α and TGF-β production by human keratinocytes. TNF-α and TGF-β levels increased over time in honey treated and untreated keratinocytes, whereas cells treated with sugar solutions that matched those of the honeys had reduced levels of both cytokines. This suggests that the non-sugar phytochemical components of the honeys may have prevented this decrease. Analysis by LC-MS confirmed that the honeys contained a diverse range of phytochemicals. Some phytochemicals e.g. pinobanksin and vanillin were present at different levels across the honey types, whereas other components, e.g. dicarboxylic acids and their glycosides, were abundant in all honeys.