chapter  10
24 Pages

- Biotin

Although a growth requirement for the “bios” fraction had been demonstrated in yeast, Boas was the rst to demonstrate the requirement for biotin in a mammal. In rats fed protein derived from egg white, Boas observed a syndrome of severe dermatitis, hair loss, and neuromuscular dysfunction known as “egg-white injury.” A factor present in liver cured the egg-white injury and was named

10.1 History of Discovery............................................................................................................. 397 10.2 Chemistry of Biotin .............................................................................................................. 398

10.2.1 Structure ................................................................................................................... 398 10.2.2 Chemical Synthesis of Biotin ................................................................................... 399

10.3 Physiology of Biotin ............................................................................................................. 399 10.3.1 Digestion of Protein-Bound Biotin ........................................................................... 399 10.3.2 Intestinal Absorption of Biotin ................................................................................. 399 10.3.3 Transport of Biotin from the Intestine to Peripheral Tissues ...................................400 10.3.4 Transport of Biotin into the Liver .............................................................................400 10.3.5 Transport of Biotin into the Central Nervous System .............................................. 401 10.3.6 Renal Handling of Biotin ..........................................................................................402 10.3.7 Placental Transport of Biotin ....................................................................................402 10.3.8 Transport of Biotin into Human Milk ......................................................................402