Production of value-added carotenoids utilizing geometric isomerization technology

Carotenoids are a group of fat-soluble natural pigments that are distributed in many plants and microorganisms. They have a large number of geometric isomers owing to the E/Z-isomerization at arbitrary positions of the multiple conjugated double bonds. Dietary carotenoids offer multiple health benefits by reducing the risk of disease, particularly certain cancers and eye diseases, and their oral intake and application also have skin-improving effects. Thus, demand for carotenoid-containing supplements and cosmetics has grown rapidly in recent years. However, the low bioavailability of carotenoids in the human body poses a significant challenge for their industrial application. Recent studies have demonstrated the superior bioavailability and biological activity of carotenoid Z-isomers compared to naturally predominant (all-E)-carotenoids, and their application is highly anticipated. This commentary focuses on the latest research of bioavailability and biological activity as well as isomerization technology of carotenoid isomers. Furthermore, the potential applications and issues in the practical use of carotenoid Z-isomers are also elaborated upon.