Thiamine Vitamin BJ

Water-Soluble Thiamine (vitamin Bj) Thiamine pyrophosphate... 

Important organic applications are to the determination of quinine and the vitamins riboflavin (vitamin B2) and thiamine (vitamin Bj). Riboflavin fluoresces in aqueous solution thiamine must first be oxidised with alkaline hexacyanoferrate(III) solution to thiochrome, which gives a blue fluorescence in butanol solution. Under standard conditions, the net fluorescence of the thiochrome produced by oxidation of the vitamin Bj is directly proportional to its concentration over a given range. The fluorescence can be measured either by reference to a standard quinine solution in a null-point instrument or directly in a spectrofluorimeter.27... 

True. Excessive alcohol use can lead to serious damage to mental health. Depression, anxiety, delusions and negative changes in personality can occur. Korsakoff s psychosis occurs in some excessive users of alcohol. This form of dementia results in disorientation, loss of memory and lowered intellectual abilities. It is reversible in some sufferers through the administration of thiamine (vitamin Bj. 

The SP procedure of water-soluble vitamins from multivitamin tablets is particularly challenging due to the diverse analytes of varied hydrophobicities and pfC. Water-soluble vitamins (WSVs) include ascorbic acid (vitamin C), niacin, niacinamide, pyridoxine (vitamin B ), thiamine (vitamin Bj), folic acid, riboflavin (vitamin B2) and others. While most WSVs are highly water soluble, riboflavin is quite hydrophobic and insoluble in water. Folic acid is acidic while pyridoxine and thiamine are basic. In addition, ascorbic acid is light sensitive and easily oxidized. The extraction strategy employed was a two-step approach using mixed solvents of different polarity and acidity as follows ... 

K-Lor, Slow-K, Micro-K, Klorvess, others) (Table VI-5) Pyridoxine [Vitamin B ] Thiamine [Vitamin BJ... 

Lipid soluble analogs of thiamine (vitamin Bj) 1126 have a number of therapeutic uses, and examples are acetiamine 1127 (R = Me), bentiamine 1127 (R = Ph), fursultiamine 1128, and octotiamine 1129 which has antiinflammatory activity. 

The stability of some vitamins is influenced by aw. In general, the stability of retinol (vitamin A), thiamin (vitamin Bj) and riboflavin (vitamin B2) decreases with increasing aw. At low av (below 0.40), metal ions do not have a catalytic effect on the destruction of ascorbic acid. The rate of loss of ascorbic acid increases exponentially as aw increases. The photodegradation of riboflavin (Chapter 6) is also accelerated by increasing aw. 

Many types of aliphatic, heterocyclic, and aromatic derived quaternary ammonium compounds are produced both in plants and invertebrates. Examples include thiamine (vitamin Bj) (4). See also Vitamin choline... 

The major vitamins are described in separate alphabetical entries in tins book. Titles used for these entries have been selected on tlie basis of the most frequently used designations as of tlie early 1980s. In alphabetical order, the vitamins described in this book are Ascorbic Acid (Vitamin C) Biotin Choline and Cholinesterase Folic Acid Inositol Niacin Pantothenic Acid Vitamin Bj (Riboflavin) Thiamine (Vitamin Bj) Vitamin A Vitamin B (Pyridoxine) Vitamin B12 (Cobalamin) Vitamin D Vitamin E and Vitamin K. 

An enzyme cofactor can be either an inorganic ion (usually a metal cation) or a small organic molecule called a coenzyme. In fact, the requirement of many enzymes for metal-ion cofactors is the main reason behind our dietary need for trace minerals. Iron, zinc, copper, manganese, molybdenum, cobalt, nickel, and selenium are all essential trace elements that function as enzyme cofactors. A large number of different organic molecules also serve as coenzymes. Often, although not always, the coenzyme is a vitamin. Thiamine (vitamin Bj), for example, is a coenzyme required in the metabolism of carbohydrates. 

The fat-soluble vitamins are A, D, E, and K. The water-soluble vitamins are thiamine (vitamin Bj), riboflavin, nicotinic acid (niacin) and nicotinamide, pyridoxine (vitamin B6), pantothenic acid, biotin, para-aminobenzoic acid, choline, inositol, and other lipotropic agents, ascorbic acid (vitamin C), the riboflavonoids, folate, and vitamin B12 (see Figure 66.1 and Figure 66.2, and Table 66.1). 

The thiazole ring can be found in numerous molecules that possess biological activity the thiamine (vitamin Bj), penicillins, antiinflamatory and bactericidals compounds, and so forth. 

Thiazole gives a transient radical in aqueous solution upon pulse radiolysis. The radical formed under neutral conditions is the 3-hydrothiazolyl radical (201) for which electronic absorption spectra, acid-base characteristics, and second-order decay kinetics were measured. A derivative of this, the radical from thiamine (vitamin Bj) (202) was also characterized. A role is implied for related radicals (e.g., 203) during the electrochemical dimerization reported for benzothiazolium salts. ... 

Synonyms Vitamin Bj Aneurine hydrochloride Thiamine hydrochloride Thiadoxine Thiamin Vitamin Bj hydrochloride... 

Arnold, R.G., Libbey, L.B., Lindsay, R.C. Volatile flavor compounds produced by heat degradation of thiamine (vitamin Bj). J. Agric. Food Chem. 1969, XL, 390-392. 

Thiamine (vitamin Bj) is an important water-soluble vitamin that, in its active form of thiamine pyrophosphate, is used as a cofactor in enzymatic reactions that involve the transfer of an aldehyde group. Thiamine can be synthesized by plants and some microorganisms, but not usually by animals. Hence, humans must obtain thiamine from the diet, though small amounts may be obtained from synthesis by intestinal bacteria. Because of its importance in metabolic reactions, it is present in large amounts in skeletal muscle, heart, liver, kidney, and brain. Thus, it has a widespread distribution in foods, but there can be a substantial loss of thiamine during cooking above 100°C (212°F). 

Figure 15-1. Activation of thiamine (vitamin Bj) to the active cofactor, thiamine pyrophosphate (TPP) by the enzyme TPP synthetase.

A deficiency in thiamine (vitamin Bj) would most likely lead to which of the following clinical manifestations ... 

Thiamine (vitamin Bj) is an important water-soluble vitamin that, in its active form of thiamine pyrophosphate, is used as a cofactor in enzymatic reactions that involve the transfer of an aldehyde group. 

Several highly significant vitamins are water-soluble and heterocychc in nature and further, their utility in the co-enzymes into which they are incorporated, can only be understood on the basis of their intrinsic heterocychc reactivity. We consider in detail firstly the two important pyridine-containing vitamins -vitamin B3 (niacin or nicotinamide) and vitamin Bg (pyridoxine) and then the thiazole-containing thiamin (vitamin Bj). 

Vitamin C and thiamine (vitamin Bj) have been studied extensively since they are water soluble, highly susceptible to chemical degradation, and present in many foods they are also required in the diet and are sometimes deficient in the diet (Fennema,... 

---