Canthaxanthin: From molecule to function.

The aim of this review is to summarize the relevant literature about the use of canthaxanthin in food science and nutrition research. Canthaxanthin is a red-orange carotenoid that belongs to the xanthophyll group. This naturally occurring pigment is present in bacteria, algae and some fungi. Canthaxanthin is also responsible for the color of flamingo feathers, koi carp skin and crustacean shells. Canthaxanthin is widely used in poultry (broiler, laying hens) as a feed additive. Canthaxanthin can be obtained by total synthesis. The canthaxanthin-mediated color of foods is an important quality criterion for consumers. Recently, the potential health-promoting effects of canthaxanthin have been discussed. Canthaxanthin enrichment of LDL has the potential to protect cholesterol from oxidation. In addition to its free radical scavenging and antioxidant properties (e.g., the induction of catalase and superoxide dismutase), canthaxanthin's immunomodulatory activity (e.g., enhancing the proliferation and function of immune competent cells) and its important role in gap junction communication (e.g., induction of the transmembrane protein connexin 43) have been reported. Many studies regarding the potential health benefits of canthaxanthin have been conducted in vitro and should be validated in appropriate in vivo models.