fucoxanthine

Fucoxanthin is a natural xanthophyll carotenoid found primarily in brown algae (Phaeophyceae) and in certain diatoms and haptophytes. It is the pigment that gives many brown seaweeds their characteristic color and contributes to photosynthetic light harvesting by absorbing blue-green light.

Chemically, fucoxanthin features a conjugated polyene chain with unique structural motifs, including an allenic bond and an epoxide. It is highly lipophilic and relatively stable to heat compared with some other carotenoids.

Occurrence and sources: It is a major pigment in many edible brown seaweeds, such as Undaria pinnatifida (wakame) and Laminaria spp., and can also be found in microalgae. It is extracted for research, nutraceuticals, and as a natural colorant in some products.

Biological activity: In preclinical studies, fucoxanthin has shown antioxidant, anti-inflammatory, anti-obesity, and anti-cancer–related effects, often via modulation of adipose tissue metabolism, oxidative stress, and signaling pathways. Clinical evidence in humans remains limited and inconclusive.

Metabolism and bioavailability: In mammals, fucoxanthin is rapidly hydrolyzed to fucoxanthinol in the intestine and further metabolized to amarouciaxanthin A in the liver; these metabolites are thought to contribute to observed biological effects. Bioavailability depends on formulation and dietary fat.

Safety and regulation: Dietary intake from seaweeds is common in East Asia; supplement use is marketed but lacks robust long-term safety data. Product quality and standardization vary.