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Vitamin application effects

Vitamin is one of the most extraordinary and effective catalysts working in biological systems The application of natural as well as its cyanocobalamine... [Pg.69]

It was observed leldivdy early that chonically labile compounds - such as vitamins, carotenes - decomixise, either on application to the TLC layer or during the TLC separation that follows. Ibis phenomenon was primarily ascribed to the presence of oxygen (oxidation) and exposure to light (photochemical reaction) in the presence of the active sorbents, which were assumed to exert a catalytic effect (photocatalytic reaction). [Pg.14]

One of the few phytochemicals that has been subjected to the rigorous testing procedures required by food safety authorities is P-carotene, a naturally-occurring carotenoid that is also a pre-cursor of vitamin A in humans. It is increasingly used as a food colour since the food product can be claimed to contain all natural ingredients. For this reason, detailed toxicological studies were undertaken that enabled the Joint FAO/WHO Expert Committee for Food Additives (JECFA) to set an ADI of 0-5 mg/kg/bw/day based on a NOAEL of 50 mg/day and the application of an uncertainty factor of 10 (JECFA, 1974). This low factor was used because it was argued that the compound occurred naturally in food, that its use as a food additive would not lead to a substantial increase in the total amount normally consumed, and that there had been no reports of adverse effects in humans. The ADI would correspond to an acceptable intake in humans of up to 350 mg/day. [Pg.229]

Squalene is an isoprenoid compound that is found in large quantities in shark liver and in smaller quantities in olives, rice bran and wheat germ. It is a bactericidal compound and an antioxidant and it aids in skin nutrition. Several cosmetic applications of rice bran and rice bran oil arise from the biological effects of their squalene, vitamin E and y-oryzanol content. Since these compounds are fat-soluble, rice bran oil is used for all these preparations. [Pg.362]

The literature on basic- and acid-catalyzed alkylation of phenol and of its derivatives is wide [1,2], since this class of reactions finds industrial application for the synthesis of several intermediates 2-methylphenol as a monomer for the synthesis of epoxy cresol novolac resin 2,5-dimethylphenol as an intermediate for the synthesis of antiseptics, dyes and antioxidants 2,6-dimethylphenol used for the manufacture of polyphenylenoxide resins, and 2,3,6-trimethylphenol as a starting material for the synthesis of vitamin E. The nature of the products obtained in phenol methylation is affected by the surface characteristics of the catalyst, since catalysts having acid features address the electrophilic substitution in the ortho and para positions with respect to the hydroxy group (steric effects in confined environments may however affect the ortho/para-C-alkylation ratio), while with basic catalysts the ortho positions become the... [Pg.347]

Other mediators which have been used in combination with diaphorase for the regeneration of NAD+ are riboflavin and Vitamin K3, which is 2,3-dimethyl-1,4-naphthoquinone. However, especially riboflavin is not stable enough for synthetic applications [40]. Better stability is exhibited by phenanthrolindiones as mediators. In combination with diaphorase, Ohshiro [41] showed the indirect electrochemical oxidation of cyclohexanol to cyclohexanone using the NAD+ dependent HLADH with a turnover frequency of two per hour. For an effective enzymatic synthesis, this turnover frequency, however, would be too small. In our own studies, we were able to accelerate the NAD(P)+ regeneration considerably by lowering the electron density within the... [Pg.99]

Cholin chloride, shown in Scheme 1, was recently shown to be a versatile cationic precursor for the preparation of a wide variety of ionic liquids (48). This precursor is particularly interesting, as cholin is a vitamin B4 additive to animal food. Therefore, it is not expected to be restricted in applications by health-related concerns, whereas a number of other ionic liquids remain to be fully evaluated for their environmental and health effects, including the ones based on imidazolium ions. [Pg.163]

The therapy of atrophic rhinitis by means of vitamin A-containing nose drops showed that high-dose topical application of the vitamin leads to the restitution of mefaplastically modified nasal mucosa, side effects, especially differentiation impairments, were not reported (Breuninger and Kahn, 1960 Duncan and Briggs, 1962). [Pg.188]

The obtained results confirm earlier findings where vitamin A-deficient rats were used to prove the uptake of retinyl esters into lung, liver, kidney, and plasma after inhalation thereof (Biesalski, 1996). However, long-term topical administration of high vitamin A concentrations is a well-established therapy in atrophic rhinitis, rhinitis sicca, and metaplastic changes in the nasal or ocular epithelium (Deshpande et ah, 1997 Simm, 1980). The application leads to the normalization of mucous membranes and reappearance of a normal function with no side effects. [Pg.200]

Biesalski, FI. K. (1996). Effects of intratracheal application of vitamin A on concentrations of retinol derivates in plasma, lungs and selected tissue of rats. Int. ]. Vitam. Nutr. Res. 66, 106-112. [Pg.211]


See other pages where Vitamin application effects is mentioned: [Pg.226]    [Pg.167]    [Pg.309]    [Pg.164]    [Pg.167]    [Pg.320]    [Pg.125]    [Pg.9]    [Pg.32]    [Pg.758]    [Pg.942]    [Pg.40]    [Pg.89]    [Pg.208]    [Pg.164]    [Pg.83]    [Pg.434]    [Pg.202]    [Pg.213]    [Pg.183]    [Pg.184]    [Pg.194]    [Pg.194]    [Pg.197]    [Pg.197]    [Pg.198]    [Pg.199]    [Pg.200]    [Pg.257]    [Pg.759]    [Pg.943]    [Pg.226]    [Pg.770]    [Pg.1704]    [Pg.302]    [Pg.476]    [Pg.202]    [Pg.347]    [Pg.268]    [Pg.802]   
See also in sourсe #XX -- [ Pg.194 , Pg.197 , Pg.198 , Pg.199 , Pg.200 , Pg.201 ]




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