Characterizing antioxidant and chemopreventive properties of Polish varietal honeys after applying gastrointestinal digestion and using absorption models

• Applicant: Professor Dr. Sascha Rohn
• Subject Area: Food Chemistry
• Term: since 2022
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 504853652

Honey is a natural food product having significant nutritional as well as preventive and curative value. Numerous scientific publications point out that regular consumption of honey is one of the best forms of providing the organism with biologically-active and bacteriostatic substances, organic acids, selected indispensable amino acids as well as macro- and micronutrients. Its biological action is hypothesized to be related to significant amounts of antioxidant phenolic compounds. These are very effective antioxidants for preventing those lifestyle diseases that are based on the so called ‘oxidative stress’. As honey originates from various plants and geographical regions, the content of bioactive components including polyphenols can vary. Moreover, due to processing by the bees and the beekeeper, its compounds are transformed. Further changes take place in human gastrointestinal tract influencing composition and thus, bioavailability and bioactivity. As bioavailability of phenolic compounds is highly depending on their chemical structure, it is crucial to elucidate those. Many studies have been conducted on the exact mechanism of antioxidant capacity of honey and component’s structures responsible for this feature, but it has not been comprehensively clarified yet. Moreover, although there were some in vivo and in vitro studies that confirmed the therapeutic and/or preventive potential of selected varieties of honey of various origin, there is a scarce research considering structural changes during processing and after digestion and the following trans-epithelial transport. Consequently, bioactivity is not yet explained comprehensively. Polish dark varietal honeys provide the highest total phenolic contents worldwide and therefore, they can serve as models for the bioactivity. The main objective of this research is to characterize honey’s biological activity, including antioxidant responsibility and chemopreventive properties of selected Polish honey varieties with consideration of postharvest influence on structural changes of the polyphenols (degradation and follow-up products) and their behavior during digestion and absorption. This research will cover the whole value-added chain, including verification of the botanical origin using pollen analysis and physicochemical methods, simulation of the digestion and trans-epithelial transport, determination of the total phenolic content and composition, and characterization of the contribution of single compounds to the overall antioxidant activity by quantification of antioxidant compounds (polyphenols and their degradation and reaction products). Chemopreventive properties of honey and its fractions will be correlated with antioxidant compounds structure changes. Cell cultures experiments will provide information on the impact of the tested honeys on the viability, proliferation and metabolic activity of various tumor cells.

• DFG Programme: Research Grants
• International Connection: Poland
• Cooperation Partners: Dr.-Ing. Michal Halagarda; Professorin Dr.-Ing. Zofia Niziol-Lukaszewska