The carotenoid fucoxanthin from brown seaweed affects obesity

The unique and phenomenal biodiversity of the marine environment provides a large pool of novel and bioactive molecules. Fucoxanthin, a characteristic carotenoid found in brown seaweeds, shows anti‐obesity effect on the basis of specific molecular mechanism. Nutrigenomic study reveals that fucoxanthin induces uncoupling protein 1 expression in white adipose tissue (WAT) mitochondria leading to oxidation of fatty acids and heat production in WAT. Fucoxanthin improves insulin resistance and decreases blood glucose level, at least in part, through the down‐regulation of TNFα in WAT of animals. Furthermore, the anti‐obesity effect of fucoxanthin is likely linked to its structural characteristic – an allene bond and an additional hydroxyl substituent on the side group of the fucoxanthin metabolites, fucoxanthinol and amarouciaxanthin A. Thus, there is growing interest in fucoxanthin as a major molecule for the increasing biological significance of seaweed lipids. Our recent study showed that total lipids belonging to Sargassaceae species are rich in fucoxanthin as well as other bioactive compounds such as omega‐3 (20:5n‐3 and 18:4n‐3) and omega‐6 (20:4n‐6) highly unsaturated fatty acids (HUFA), fucosterols, and polyphenols. The importance of these omega‐3 and omega‐6 HUFA on human health has been proven beyond any doubt. Fucosterols and polyphenols are also known to show beneficial health effects. Furthermore, we found a synergistic effect of omega‐3 HUFA on the anti‐obesity effect of fucoxanthin. Therefore, brown seaweed lipids are expected to be a good source for functional food ingredients.