Retinol is one of the animal forms of which vitamin?
Vitamin A retinol), which is an important hormone-like growth factor for epithelial and other cells. In foods of animal origin, the major form of vitamin A is an ester, primarily retinyl palmitate, which is converted to retinol (chemically an alcohol) in the small intestine. The retinol form functions as a storage form of the vitamin, and can be converted to and from its visually active aldehyde form, retinal. All forms of vitamin A have a beta-ionone ring to which an isoprenoid chain is attached, called a "retinyl group". Both structural features are essential for vitamin activity. The orange pigment of carrots (beta-carotene)
Retinol dehydrogenase specifically those acting on the CH-OH group of donor with NAD or NADP as acceptor. The systematic name of this enzyme class is retinol:NAD oxidoreductase. Other names in common use include retinol (vitamin A1) dehydrogenase, MDR, microsomal retinol dehydrogenase, all-trans retinol dehydrogenase, retinal reductase, and retinene reductase. This enzyme participates in retinol metabolism. Occasionally, the literature refers to retinol dehydrogenase as an enzyme that oxidizes retinol in general, such as class IV alcohol dehydrogenase (ADH4), which reportedly is the most efficient retinol oxidation in the human alcohol dehydrogenase (ADH) family. As one of the most important RDH, 11-"cis"-retinol dehydrogenase catalyzes