A 20-carbon dicarboxylic acid which is a diterpenoid and natural carotenoid. Found in the crocus flower, it has been administered as an anti-fatigue dietary supplement. ChEBI: Crocetin is a 20-carbon dicarboxylic acid which is a diterpenoid and natural carotenoid. Found in the crocus flower, it has been administered as an anti-fatigue dietary supplement. It has a role as a nutraceutical, a metabolite and an antioxidant. It is a carotenoic acid, a diterpenoid and a polyunsaturated dicarboxylic acid. It is a conjugate acid of a crocetin(2-).