Rhodoxanthin: The new hit of the natural carotenoids market?

Background: The scientific evidence linking several diseases to human diet has highlighted the beneficial impacts of various natural food components, including carotenoids. The xanthophyll rhodoxanthin is a type of retrocarotenoid that might exert positive health-promoting actions. Scope and approach: There is increasing evidence that rhodoxanthin exerts potential health-promoting biological activity in both in vitro and in vivo models, and some patents are available for food applications. However, as a food additive, rhodoxanthin is currently approved for use only in Australia and New Zealand. Considering the importance of carotenoids and their relevance to the market, this review provides a comprehensive description of natural rhodoxanthin, covering its distinctive properties and potential health-promoting actions. Moreover, the most promising advancements in the production, recovery, application and regulatory framework of this pigment from both plant and microbial sources are also considered. Lastly, we offer our expert perspective to the readers on the potential of rhodoxanthin as a prominent natural carotenoid in the food market. Key findings and conclusions: It can be concluded that rhodoxanthin is a scarcely studied carotenoid with an unusual and interesting chemical structure that endows it with properties (such as color or antioxidant capacity) that are amenable for industrial applications in different sectors. The scarcity of studies about this carotenoid as well as its absence in common dietary sources offer both challenges and innovation opportunities. More research is needed to determine whether rhodoxanthin can 'compete with' or even 'surpass' carotenoids with a wellestablished market, such as canthaxanthin, lycopene or astaxanthin. Overall, we identify main knowledge gaps and research opportunities for application of rhodoxanthin in several industries.