Combination of resveratrol, lecithin and vegetable oil for complete replacement of fish oil in fish feeds

• Applicant: Professor Dr. Gerald Rimbach
• Subject Area: Animal Breeding, Animal Nutrition, Animal Husbandry
• Term: since 2023
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 519135288

Fish is considered an important and healthy food primarily due to its fatty acid composition. Particular attention is paid to the long-chain highly unsaturated omega-3 (n-3) fatty acids (HUFA) such as eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). As yields from fisheries have stagnated since several decades, the growing global demand of fish for human nutrition has been increasingly met by the aquaculture sector. To meet the demand for EPA- and DHA-rich fish due to aquaculture, lipid sources in fish feed are critical. However, one of the most important lipid sources in fish feed - fish oil - has been increasingly replaced by vegetable fat sources over the past years. This means that the fatty acid composition in aquaculture derived fish no longer meets the recommendations for increased intake of long-chain omega-3 fatty acids in humans. Therefore, an important goal of aquaculture is currently to substantially increase the content of n-3 HUFA in fish products without increasing the portion of fish oil in fish feed per se. In our previous project, controlled feeding studies demonstrated that the stilbene resveratrol in the diet of rainbow trout (Oncorhynchus mykiss, W., 1792) led to a significant increase in EPA and DHA in the fish body. However, the use of resveratrol in the feed resulted in reduced energy digestibility of the feed, as well as decreased feed intake of the fish. In the present project, these negative outcomes are aimed to be compensated using lecithin produced by the application partner. Thus, the purpose of the project is to use a mixture of resveratrol, lecithin and vegetable oil to achieve a complete replacement of fish oil in fish feed without compromising growth performance. Complementary to the in vivo feeding experiments, mechanistic in vitro cell culture studies, will be applied to unravel the combined effect of resveratrol and lecithin at the molecular level. Due to the complementary project team conducting the corresponding in vivo and in vitro experiments, a new research area for investigating combined compounds will be established at the TRL7. Overall, our project has the potential to address numerous research questions, and it will lead to additional commercial collaborations between Fraunhofer, industrial partners and the university. Furthermore, it will advance the commercial exploitability of the results of the predecessor project.

• DFG Programme: Research Grants (Transfer Project)
• Application Partner: Marvesa Oils & Fats B.V
• Cooperation Partner: Professor Dr. Carsten Schulz