Human Nutrition 3(3+0)

Lesson 24 : Thiamine (Vitamin B1)

Physiological and biochemical functions

• Thiamine is required for normal growth.
• It is essential for maintaining the nerves in normal condition. Degeneration of the myelin sheaths of the peripheral nerves and also of the ganglion cells of the brain and spinal cord takes place in thiamine deficiency.
• Thiamine participates in several enzymic reactions as a co-enzyme (co-carboxylase) such as decarboxylation of pyruvic acid and other ketoacids.
• As thiamine pyrophosphate (TPP), thiamine is required in oxidative decarboxylation of ?-ketoglutarate to succinate and the oxidation of pyruvate to the active acetyl group
• Thiamine pyrophosphate is utilized as coenzyme for the transketolase activity in R.B.C. for the transfer of a 2-carbon unit from a 2-keto sugar to C-1 of various aldoses.