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Related to thiamin: riboflavin, folate


see coenzymecoenzyme
, any one of a group of relatively small organic molecules required for the catalytic function of certain enzymes. A coenzyme may either be attached by covalent bonds to a particular enzyme or exist freely in solution, but in either case it participates intimately in
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; vitaminvitamin,
group of organic substances that are required in the diet of humans and animals for normal growth, maintenance of life, and normal reproduction. Vitamins act as catalysts; very often either the vitamins themselves are coenzymes, or they form integral parts of coenzymes.
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A water-soluble vitamin found in many foods; pork, liver, and whole grains are particularly rich sources. It is also known as vitamin B1 or aneurin. The structural formula of thiamine is shown below.

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Thiamine deficiency is known as beriberi in humans and polyneuritis in birds. Muscle and nerve tissues are affected by the deficiency, and poor growth is observed. People with beriberi are irritable, depressed, and weak. They often die of cardiac failure. Wernicke's disease observed in alcoholics is associated with a thiamine deficiency. This disease is characterized by brain lesions, liver disease, and partial paralysis, particularly of the motor nerves of the eye. As is the case in all B vitamin diseases, thiamine deficiency is usually accompanied by deficiencies of other vitamins.



(vitamin B1; aneurine), a heterocyclic compound that is one of the water-soluble vitamins. It consists of colorless crystals with a characteristic odor.

Thiamine was first isolated from rice hulls by the Polish scientist K. Funk in 1912 and later was obtained synthetically. In nature, thiamine is synthesized by plants and certain microorganisms; it is found in the greatest quantities in brewers’ yeast, cereal grains, and potatoes. Animals and humans obtain thiamine from food. A shortage of thiamine in the diet results in the appearance of a serious disease, polyneuritis (in beriberi).

The physiological significance of thiamine results from the coenzyme functions of its pyrophosphoric ester, thiamine pyrophosphate (cocarboxylase). The daily requirement of thiamine for humans is 1.5–2 mg. Thiamine and its phosphoric esters and disulfide derivatives are used to treat peripheral neuritis, diabetes mellitus, disorders of the cardiovascular system, and other diseases associated with disruption of carbohydrate metabolism.


Ostrovskii, Iu. M. Tiamin. Minsk, 1971.


C12H17ClN4OS A member of the vitamin B complex that occurs in many natural sources, frequently in the form of cocarboxylase. Also known as aneurine; vitamin B1.


, thiamin
Biochem a soluble white crystalline vitamin that occurs in the outer coat of rice and other grains. It forms part of the vitamin B complex and is essential for carbohydrate metabolism: deficiency leads to nervous disorders and to the disease beriberi. Formula: C12H17ON4SCl.H2O
References in periodicals archive ?
Low in sodium, it is also a good source of thiamin, and manganese.
Maximum inhibition was reflected by I2 with G1, G2 concentration of glucose, while I3 concentration of thiamin was overall efficient towards inhibition with G3 and G4 (Figure-3).
INGREDIENTS: Enriched Wheat Flour (Wheat Flour, Niacin, Reduced Iron, Thiamin Mononitrate, Riboflavin, Folic Acid), Sunflower Oil (Rosemary Extract, Ascorbic Acid) and/or Canola Oil (Rosemary Extract, Ascorbic Acid), Sea Salt, Whole Wheat Flour, and Less than 2% of the Following: Organic Cane Sugar, Oat Fiber, Active Yeast, Compressed Yeast, Inactive Yeast, and Malted Barley Flour.
Table 10-9 gives thiamin requirements for selected livestock.
On the other hand, in addition to getting enough protein and carbohydrates, Americans also take in sufficient amounts of such key nutrients as niacin, selenium, riboflavin, thiamin, folate and iron.
First I could not see thiamin (as coenzyme) in four of its six metabolic roles (easily corrected in the next edition).
Not only is British pork lean, but it is also nutritious, containing protein, iron, zinc, thiamin and vitamins B12 and D ( which are all essential for healthy growth and maintained health.
Vitamins such as potassium, vitamin C, vitamin A, folate, thiamin, iron, zinc, niacin, malic acid and other important necessary elements such as fiber and sugars are all present in fruits and fruit juices.
To state that we should discard all of them because one does not behave as expected would be similar to stating that vitamin B has no role in cardiovascular risk management because thiamin might prove statistically doubtful.
While canned carrots did not contain as much beta-carotene, thiamin and folate as the fresh variety, they did provide a similar amount of other vitamins and minerals.
12], thiamin, riboflavin, folate, calcium, magnesium, iron, zinc, niacin, phosphorus) by replacing the more healthful alternatives that typically contain these nutrients.