Material 9 Vitamins Folate

Folic Acid (folate). Chemically, folic acid is a pteryl-glutamic acid. The several forms that occur in nature depend on the numbers of glutamic acid units and methyl groups in the molecules. Because of its usual low concentration, folic acid is generally determined in food materials by the microbiological assay with lactobacillus casei and measured turbidimetrically or titrimetrically. Deficiency of this vitamin could result in... 

Elucidation of the structure of the B vitamins resxilted in the development of analytical chemical methods. Such methods are useful in industries manufacturing vitamins in which measurements of microgram to milligram quantities are routine, but these same methods are often not applicable to biological fiuids that contain as little as picogram quantities. Colorimetric and fluorometric techniques have been developed for niacin and folate, but these techniques require complicated extraction procedures and blank determinations. They also suflFer from lack of specificity, and the results are often altered by interference from biologically inactive materials that occur naturally or are produced during extraction (16,20). 

The RMA have been shown to be simple, sensitive, and specific for the measurement of vitamin B12, folate, and niacin in the blood and for the measurement of vitamin B12 and folate in food. Further work will be carried out for the measurement of niacin in food. For the determination of the biologically active forms of niacin, the RMA is more specific than the TMA. The RMA is also more specific than the CPBA for the measurement of vitamin B12. The advantages of the RMA over the TMA are (i) it is sensitive and simple (ii) the colored or turbid materials do not interfere with the assay (iii) only small amounts of material are required and most important, (iv) RMA combines the biological specificity of the microorganisms with the precision of measuring radioactive decay as the endpoint. 

The curative material, which is abundant in green leafy vegetables, was named folic acid. However, this name is usually reserved for the synthetic compound used in dietary supplementation. The natural forms are largely the coenzymes (Fig. 6), which are collectively called folates. The last of the accepted human vitamins to be discovered was vitamin Bn. A cobalt-containing organic compound needed in very small amounts, it cures and prevents pernicious anemia, which was often a fatal disease of people over 60 years of age. Its complex structure (Fig. 7) was determined by X-ray diffraction after numerous efforts at chemicai characterization had failed. However, cy anocobalamin, the compound isolated and the form used in nutritional supplementation, is an artifact of the isolation and synthesis. The natural vitamin may have OH in place of CN but consists largely of the coenzyme forms. 

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