Thiamine with vitamin

Thiazolium salts with alkyl (103, 722), arylalkyl (116), aryl (305), or heteroaryl (96) substituents on the nitrogen have been also prepared by this procedure. As in the thiazole series, N-substituted thioamides can be formed directly in the reaction mixture from phosphorus pentasulfide and N-substituted amides (127). These methods are important in the synthesis of thiamine 102 (vitamin Bj) (Scheme 45). 

Water-soluble vitamins removed by hemodialysis (HD) contribute to malnutrition and vitamin deficiency syndromes. Patients receiving HD often require replacement of water-soluble vitamins to prevent adverse effects. The vitamins that may require replacement are ascorbic acid, thiamine, biotin, folic acid, riboflavin, and pyridoxine. Patients receiving HD should receive a multivitamin B complex with vitamin C supplement, but should not take supplements that include fat-soluble vitamins, such as vitamins A, E, or K, which can accumulate in patients with renal failure. 

The interaction of metal ions with vitamin Bi (thiamine hydrochloride, 135) continues to be of interest, and a combination of IR, XH and 13C NMR techniques have been applied to the... 

An especially interesting coenzyme is thiamine pyrophosphate (vitamin Bx) which, in conjunction with the appropriate enzyme, decarboxylates 2,-oxopropanoic acid (pyruvic acid Section 20-1 OB). We can write the overall reaction as follows ... 

Individuals on long-term diuretic therapy may also experience elevated levels of homocysteine, an amino acid regulated by folate. High homocysteine levels increase the risk of heart disease. Thiamin, or vitamin Bj, depletion is another possible side effect of loop diuretics. Individuals with thiamin deficiencies are at risk for fatigue, heart enlargement, muscle cramps, heart rate irregularities, and impaired mental function. 

Both drugs and compounds naturally present in foods may compete with vitamins for absorption. Chlorpromazine, tricyclic antidepressants, and some antimalarial dmgs inhibit the intestinal transport and metabolism of riboflavin (Section 7.4.4) carotenoids lacking vitamin A activity compete with /S-carotene for intestinal absorption and metabolism (Section 2.2.2.2) and alcohol inhibits the active transport of thiamin across the intestinal mucosa (Section 6.2). 

Inadequate saturation of enzymes with (vitamin-derived) coenzymes. This can be tested for three vitamins, using red blood cell enzymes thiamin (Section 6.5.3), riboflavin (Section 7.5.2), and vitamin Be (Section 9.5.3). 

Vision loss may occur in deficiency states (thiamine or vitamin B12) or as a toxic response to certain drugs or substances (Box 22-5). In most cases one can establish that the patient has been exposed to toxins or has had some dietary deficiency. The precise pathogenesis of the atrophic process is somewhat obscure, although adenosine triphosphate formation appears to undergo a change. This change leads to a stasis of axoplasmic flow with subsequent optic disc edema, eventually resulting in axonal death. 

These various reports stress the need to supplement parenteral nutrition with thiamine-containing vitamins unless there is adequate dietary intake, and to monitor serum thiamine and erythrocyte transketolase activity so that supplementary thiamine can be given in good time, if necessary intravenously (45). Giving thiamine will not rectify the various disorders if hepatic function is severely disturbed, because then thiamine is not phosphorylated and hence remains physiologically inactive. 

The quantitative analysis of thiamine hydrochloride (vitamin Bj), using HPTLC on silica gel plates with two different mobile phases, was elaborated.After TLC separation, vitamin Bj was derivatized by the use of ferf-butyl hypochlorite or potassium hexocyanoferrate (Ill)-sodium hydroxide as reagents. The ferf-butyl... 

Thiamine hydrochloride (vitamin Bi hydrochloride, HC12-H17ON4SCI2) is a weak acid with = 3.4 X 10. Suppose 3.0 X 10 g of thiamine hydrochloride is dissolved in 1.00 L of water. Calculate the pH of the resulting solution. [Hint This is a sufficiently dilute solution that the autoionization of water cannot be neglected.)... 

Figure 2 Anaerobic acidogenic fermentation of sediment mud suspension without vitamin addition (a) and with vitamin addition (b). The vitamin concentration added to the suspension was 1 mg/L of thiamine, I mg/L of nicotinic acid and 10 gg/L-of biotin. . 200 g sediment mud/L artificial sea water , 400 g sediment mud/L artificial sea water.

Typically, soymilk contains 8-12% total solids, depending on the water bean ratio used during processing. Protein content is about 3.6% fat, 2.0—3.2% carbohydrates, 2.9—3.9% and ash, -0.5%. The composition of soymilk compares favorably with those of cow s milk and human milk (Chen, 1989). In addition, soymilk is lactose-free and contains higher levels of protein, iron, unsaturated fatty acids, and niacin however, it contains lower amounts of fat, carbohydrates, calcium, riboflavin, thiamine, methionine, and lysine (Kosikowski, 1971). Therefore, many commercial soymilks are fortified with vitamins, minerals, and in some cases, amino acids. The most widely used nutrients for fortifying soymilk are vitamin calcium, and methionine. 

Several reagents and reaction conditions such as TMSI (generated in situ from TMSCl and Nal), magnesium nitride (Mg3N2), triphenylphosphine (PPhs), thiamine hydrochloride (vitamin mnding under solvent-free conditions, PTSA with ultrasonic irradiation were recently reported to mediate efficiently the Hantzsch dihydropyridine synthesis. For instance, 1,4-dihydropyridines 143 were obtained in good yields using thiamine hydrochloride (vitamin B ) as the catalyst under solvent-free conditions at room temperature. ... 

A Tolerable Upper Intake Level (UL) is the highest level of daily nutrient intake that is likely to pose no risk of adverse health effects to almost all individutils in the general population. Unless otherwise specified, the UL represents total intake from food, water, and supplements. Due to alack of suitable data, ULs could not be established for vitamin K, thiamin, riboflavin, vitamin B, pantothenic acid, biotin, and carotenoids. In the absence of a UL, extra caution may be warranted in consuming levels above recommended intakes. Members of the general population should be advised not to routinely exceed the UL. The UL is not meant to apply to individuals who are treated with the nutrient under medical supervision or to individuals with predisposing conditions that modify their sensitivity to the nutrient As preformed vitamin A only... 

A number of amines are vitamins. These include nicotinic acid and nicotinamide, pyridoxine (vitamin Be, see The Chemistry of... Pyridoxal Phosphate in WileyPLUS for Chapter 16), and thiamine chloride (vitamin B-, see The Chemistry of... Thiamine," in WileyPLUS for Chapter 17). Nicotine is a toxic alkaloid found in tobacco that makes smoking habit forming. Histamine, another toxic amine, is found bound to proteins in nearly all tissues of the body. Release of free histamine causes the symptoms associated with allergic reactions and the common cold. Chlorpheniramine, an antihistamine, is an ingredient of many over-the-counter cold remedies. 

Vitamin B, is thiamine (ll.lOSd), which is often encountered in coenzyme form as thiamine pyrophosphate. It can be made by phosphorylation of thiamine with ATP (11.105). This anti-beri-beri vitamin was first isolated and synthesised in 1936. Thiamine is found as free B, mostly in plants. It usually occurs in pyrophosphate form in yeast and in tissue. 

NB When the bases occur in nucleic acids, adenine, guanine and cytosine are present in both RNA and DNA uracil is found only in RNA and thymine is found only in DNA. Attention do not confuse thymine with vitamin Bj which is thiamin... 

Most media contain water-soluble B vitamins. Common to many formulations are vitamins Bi (thiamine), B2 (riboflavin), B3 (niacinamide), Bj (pantothenic acid). Be (pyridoxine), and Bg (folic acid). Biotin (vitamin H), cyanocobalamin (vitamin B]2 ), and ascorbic acid (vitamin C) are also common vitamin components. Although choline and inositol are classically grouped with vitamin components, in cell culture they function as metabolic substrates rather than as catalysts. 

Thyroxine affects vitamin metabolism by interfering with the requirement of a vitamin and interfering with vitamin biosynthesis. The requirements for thiamine and riboflavin, two vitamins involved in the cell s... 

The pure crystalline vitamin was obtained in Java in 1927 by Barend Jansen and William Donath, who were both students of Eijkman (Jansen and Donath 1927). Robert Williams developed an effective method to isolate vitamin B from rice bran, proposed its structure, and confirmed it by synthesizing the compound (Williams and Cline 1936). The compound, then already given the name vitamin Bi, had a thiazole ring and therefore was named thiamine (Figure 1.1). (As with vitamin , thiamine later lost its e to thiamin , although the spelling thiamine is still frequently used.)... 

Based on the oxidation of thiamin by kohlrabi extract, Amjadi et al. (2007) presented a sensitive and effective fluorimetric method for determining vitamin Bi (thiamin) in vitamin B complex tablets and syrup with good accuracy. Based on the catalytic activity of horseradish peroxidase (HRP), Khan et al. (2009) developed a new spectrofluorimetric method for the determination of vitamin Bi. HRP can oxidize the non-flu orescent compormd to a fluorescent compound in the presence of H2O2 ... 

A derivatization procedure of thiamin with orrAo-phthalaldehyde (OPA) in the presence of 2-mercaptoethanol was applied to determine vitamin Bi by FI-spectrofluorimetry (Vinas et al. 2000). The obtained LOD was at nanogram... 

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