all-trans-Retinol

Occurs preformed only in animals; metabolized from carotenoids, such b-carotene, in the intestinal mucosa. Dietary sources include liver, milk, butter, cheese, eggs and fish liver oils or as carotenois from fruits and vegetables. Stored primarily in the liver in esterified form; transported in the blood by retinol binding protein (RBP). Nutritional factor.

References: Davis, M., et al.: J. Biol. Chem., 15, 167 (1913), Crouch, R.K., et al.: Photochem. Photobiol., 64, 613 (1996),