Water-soluble vitamins applications

Ascorbic acid commonly known as vitamin C, is one of the most important water soluble vitamins. Ascorbic acid is involved in many biological processes and it is an essential compound in the human diet [1]. The determination of ascorbic acid has gained increase significance in pharmaceutic, clinical, and food applications. So far, different methods have been developed for determination of ascorbic acid [2, 3]. 

At low and medium doses, it is well established that the nutritional value of proteins, carbohydrates, and fats as macronutrients are not significantly impaired by irradiation, and neither the mineral bioavailability is impacted. Like all other energy depositing process, the application of ionizing radiation treatment can reduce the levels of certain sensitive vitamins. Nutrient loss can be minimized by irradiating food in a cold or frozen state and under reduced levels of oxygen. Thiamin and ascorbic acid are the most radiation sensitive, water-soluble vitamins, whereas the most sensitive, fat-soluble vitamin is vitamin E. In chilled pork cuts at the 3 kGy maximum at 0-10°C, one may expect about 35 0% loss of thiamin in frozen, uncooked pork meat irradiated at a 7 kGy maximum at —20°C approx., 35 % loss of it can be expected [122]. 

Most studies have investigated resorption of allergens from the small intestine, whereas little is known about resorption of allergens or other proteins from the large intestine. The large intestine is mainly recognized as the site of resorption of free water, electrolytes, and water-soluble vitamins. However, resorption of streptokinase after rectal application as well as resorption of human albumin from the large intestine have been described [1, 17, 25],... 

Among more complex macrocycles, Li et al. [47-52] reported the preparation and characterization of stationary phases incorporating calixarenes or calix-crowns bonded to silica. With individual columns, high selectivity was observed in the separation of alkylated aromatics, aromatic carboxylic acids, sulfonamides, nucleosides, and water-soluble vitamins. In other work, Sokoliess et al. [53] have characterized calixarene- and resorcinarene-bonded stationary phases similar to those described in the previous section of this chapter. And Huai et al. [54] used an end-capped p-tert-butyl-calix[4]arene-bonded silica phase for HPLC separation of a number of organic compounds. Resorcinarenes have also found application in GC. [55-57] Recently, exotic macrocycles have been used in capillary electrochromatography, as reported by Gong et al. [58]... 

Application of pyrolysis-gas chromatography for the determination of pyridoxone, HC1 and other water-soluble vitamins, has been reported (103). 

M. C. Gennaro, Separation of water-soluble vitamins by reversed-phase ion-interaction-reagent high-performance liquid chromatography Application to multivitamin pharmaceuticals, J. Chromatogr. Sci., 29 410(1991). 

Biotin (60), a water-soluble vitamin with widespread application in the growing market for health and nutrition, acts as a co-factor for carboxylase enzymes and its essential fatty acid synthesis. The key step in the chemical synthesis of biotin is the asymmetric reduction of the tetrasubstituted olefins 61 by in situ Rh(I)-4i catalyst (Scheme 12.1 S).79-83-85-86 Substrate-to-catalyst ratios of 2000 with diastereoselectivities of 99% de were achieved with Rh-4i at the multi-ton scale before production was terminated.87... 

The application of SCF to the extraction of vitamins has been widely reported. Thus, retinyl palmitate and tocopherol acetate have been extracted from a hydrophobic ointment with supercritical CO2 at 40°C and 196 bar for 4 min, the extract analysis being performed by SFC (137). The calibration graphs were linear from 0.5 to 2.5 pg and the recoveries were quantitative. On the other hand, water-soluble vitamins can be extracted mixing them with low substituted hydroxypropil cellulose. Portions were placed in a column to which a reversed micellar extractant was delivered (138). Extraction of vitamins A and E and their esters from tablet preparations prior to FIPLC was performed in the dynamic mode with CO2 at 40°C and 253 bar for 15 min (139). Calibration graphs were linear from 0.02 to 0.8 and from 0.005 to 0.2 mg/mL of vitamins E and A, respectively. The corresponding RSDs (six... 

The method of choice for the determination of most vitamins is HPLC due to its high separation capability, its mild analytical conditions, and the possibility to use various specifically adapted detection methods, e.g., LTV, fluorescence, or MS detection. All fat-soluble vitamins and most water-soluble vitamins have chromophores suitable for UV detection. Separation of vitamers and stereoisomers can be achieved. If a higher sensitivity is required HPLC with fluorescence detection can be used, either directly (e.g., vitamins A and E) or after derivatization (e.g., thiamine). A further improvement in sensitivity and specificity has been achieved by introducing HPLC with mass spectrometric detection in vitamin analysis. Due to the structural information retrievable, e.g., molecular mass, fragmentation pattern, this is the method of choice for analysis of samples with complex mixtures or low vitamin concentrations. Examples for the use of HPLC-MS in vitamin analysis include the determination of 25-hydroxy-D3 and pantothenic acid. However, one drawback of mass spectrometry is the need for an isotopically labeled reference compound for reliable quantification. Due to the structural complexity of many vitamins, these reference compounds are often expensive and difficult to synthesize. An interesting unique application is the determination of vitamin B12 by HPLC-IPC-MS, which is possible due to its cobalt content. 

Three methods of detection (UV absorbance, fluorescence, and electrochemical activity) are applicable for the analysis of water-soluble vitamins. Currently, UV absorption detection is used in many LC applications for water-soluble vitamins. A simultaneous assay of several vitamins with several wavelengths along with information of peak purity can be accomplished with a diode array absorbance detector. The detection limit of a UV detector is in the order of 1-10 ng (10-100 pmol), which is poorer than that of fluorescence and electrochemical detectors but often sufficient for analysis for many vitamins in foods and physiological samples (Table 4). The lack of selectivity of UV detection may cause problems with interfering and co-eluting contaminants especially in biological samples, thus necessitating sample purification prior to LC. 

Electrochemical detection in LC provides a sensitive assay method for certain vitamins, such as AA, folates, and flavins. AA may be easily detected with femtomolar sensitivity. Sample preparation and matrix interference problems limit the routine applicability of electrochemistry in the analysis of water-soluble vitamins currently to AA. 

Leporati, A., CateUani, D., Suman, M., Andreoli, R., Manini, R, and Niessen, W. M. A. 2005. Application of a liquid chromatography tandem mass spectrometry method to the analysis of water-soluble vitamins in Italian pasta. Anal. Chim. Acta 531 87-95. 

Thiamin plays an essential role in different foods as a water soluble vitamin. Additionally, its function as a flavor precursor in heated foods, e.g. meat, should not be neglected. But certainly, this aspect depends very much on its amoimt and the specific conditions in the food system. Another important field in which thiamin plays a remarkable role is the application of flavorings. Along with carbohydrates, amino acids, ribonucleotides, and other constituents, thiamin is widely used as a flavor precursor. This fact is clearly demonstrated by many patented reaction or processed flavors. 

Vitamin B5 or pantothenic acid is a water soluble vitamin, which is mainly produced by chemical routes. Pantothenic acid is required for normal skin function as it leads to formation of coenzyme Q and is involved in carbohydrate, protein, and lipid metabolism. Dex-panthenol, an alcoholic analog of pantothenic acid is more stable and has good skin penetration than pantothenic acid. Dexpanthenol is mainly used for topical application on skin and serves as good moisturizer and thus improves the cosmetic appearance of skin. It has mild skin inflammatory activity, but is well tolerated by skin. Pantothenic acid improves wound healing, epidermal regeneration, and reduces scarring also. So, pantothenic acid itself can be used in various skin care formulations. Pantothenic acid is used in hair care formulation as it hydrates the hair and protects the hair fiom chemicals and UV rays. ... 

The application to honey of methods developed to measure water-soluble vitamins in different matrices is a questionable analytical approach. 

Heudi, O., Kilinc, T., and Fontannaz, P., 2005. Separation of water-soluble vitamins by reversed-phase high performance Kquid chromatography with ultra-violet detection Application to polivitamined premixes. Journal of Chromatography A. 1070 49 55. 

The key step of a multivitamin method is the development of a simultaneous and quantitative extraction procedure. The intra- and intergroup heterogeneity of water-soluble vitamins makes it difficult to realize this goal. The application of an acid treatment, to hydrolyze the bound forms, can be used for simultaneous extraction of Bi, B2, B3, Bg, Bs,... 

Another application is the esterification of menahydroquinone-4, a water-insoluble vitamin K, with V,A-dimethylglycine [144], The 1-mono, 4-mono, and 1,4-bis esters were found to be water-soluble and rapidly hydrolyzable by liver and plasma esterases. A rapid pharmacodynamic response was seen after intravenous administration of the prodrugs. 

Excipients offer several possibilities and mechanisms. For microemulsions, Cremophor RH 40, Cremophor EL, and Solutol HS 15 act as surface active solubilizers in water and form the structures of micelles. The micelle that envelops the active substance is so small that it is invisible, or perhaps visible in the form of opalescence. Typical fields of application are oil-soluble vitamins, antimycotics of the miconazole type, mouth disinfectants (e.g., hexiditin), and etherian oils or fragrances. Solutol HS 15 is recommended for parenteral use of this solubilizing system and has been specially developed for this purpose. 

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