Bioavailability of biomimetic zeaxanthin aggregates in humans

• Applicant: Professor Dr. Ralf Schweiggert
• Subject Area: Food Chemistry ; Nutritional Sciences
• Term: from 2015 to 2017
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 282633789

Frequent carotenoid intake from fruits and vegetables has been associated with a lower incidence of numerous chronic diseases, such as age-related macular degeneration (AMD), cataract, cardiovascular disease, and cancer. Several carotenoids are precursors of vitamin A, for which deficiencies are being reported in 122 countries. However, carotenoid bioavailability from their natural matrix (fruits and vegetables) remains to be fully understood. Our group and, meanwhile, others have hypothesized that the natural aggregation form of carotenoids may represent a most important influence factor explaining the still poorly understood and highly variable bioavailability from foods. While carotenoids are highly bioavailable when fully dissolved in lipids, aggregated forms are commonly less bioavailable. However, most foods do not contain truly lipid-dissolved carotenoids, but most frequently different aggregate forms. The co-consumption of dietary lipids enhances the bioavailability from foods containing aggregated carotenoids, fostering their dissolution in lipids during digestion. The dissolution rate may strongly depend on the respective aggregate form. The latter may, thus, exert a substantial effect on their bioavailability. For instance, an effect of particle size has been shown previously. The bioavailability of biomimetically aggregated carotenoids has not yet been investigated in a controlled human study as proposed here. Since we will include the two most common aggregate forms found in nature (e.g., in pepper, squash, mango, papaya, carrot, tomato, and others), the presented proposal would contribute to a better understanding of carotenoid bioavailability from complex foods in general. The carotenoid zeaxanthin was selected for this study, because it is highly concentrated in human neural tissues being associated with several health benefits. Furthermore, it naturally occurs in different aggregate forms, thus being a very suitable model compound for bioavailability studies.

• DFG Programme: Research Grants
• Co-Investigator: Professor Dr. Reinhold Carle