Vitamin microbiological assay

As with many of the vitamins, biological assays have an important historical role and are widely used. For example, microbiological assays use l ctobacillusplantarum ATCC No. 8014 (57,59) or l ctobacillus arabinosus (60). These methods are appropriate for both nicotinamide and nicotinic acid. Selective detection of nictonic acid is possible if l euconostoc mesenteroides ATCC No. 9135 is used as the test organism (61). The use of microbiological assays have been reviewed (62). 

The Editors have striven, as in previous years, to include in the present volume reviews on greatly diversified subjects, all of timely importance. The article on mellituria in Volume 4 has been supplemented by a survey of galactosemia, and we expect to follow in future volumes with reviews of other inborn errors of metabolism or, in modern parlance, of molecular diseases. Likewise, the article on peptiduria supplements that on aminoaciduria in Volume 2 and that on microbiological assay of vitamins extends previous summaries on the nucleogenic vitamins. The haptoglobins lie on the borderline of hematology. 

Microbiological assay should stress accuracy over precision. Standardization of an assay method should include comparisons with at least one other organism having a different nutritional pattern and specificity toward the compound being assayed. Such a comparison was made for cyanocobalamin (vitamin Bi2 ) content of human blood and serum, using four microorganisms differing in their cobamide requirements and metabolism (B9). 

Microbiological assays for vitamin Bi2 are diverse most are simple, but require some experience and confidence. In our hands they have proved uniformity reliable for evaluating the vitamin Bi2 status of patients and are extremely useful research tools. Perhaps too much emphasis has been placed upon space, good and meticulously cleaned equipment, and trained personnel (G18). The Bi2 assays to be discussed here have been developed as practical methods. Four organisms have... 

The establishment of quantitative methods for the determination of vitamins in body fluids and tissues by microbiological assay techniques should stimulate the search for the significance of vitamins in disease, not only in nutritional deficiency, but in the much wider field of all metabolic disturbances. Functional vitamin deficiencies are produced by malabsorption, by inhibitors of the vitamin function through products of the body, and particularly through drugs and other toxic substances. Vitamin deficiencies may be relative deficiencies whenever an individual s metabolism is deranged so as to require enhanced quantities of a given vitamin to cure or to counteract certain symptoms as, e.g., in Darier s disease (keratosis follicularis) (P2a). 

B26. Barton-Wright, E. C., Microbiological Assay of the Vitamin B-Complex and Amino Acids. Pitman, London, 1952. 

F2. Ford, J. E., Microbiological assay of vitamin B12. The specificity of the requirement of Ochromonas malhamensis for cyanocobalamin. Brit. J. Nutrition 7, 299-306 (1953). 

Sobotka, H., Microbiological assays of vitamins in clinical chemistry, Clin. Chem. 4, 93-106 (1958). 

Malabsorption Syndrome, with Special Reference to the Effects of Wheat Gluten (Frazer), 5, 69 Mellituria, Nonglucose (Sidbury), 4, 29 Microbiological Assay Methods for Vitamins (Baker and Sobotka), 5, 173 Organic Acids in Blood and Urine (Nordmann and Nordmann), 4, 53 Paper Electrophoresis Principles and Techniques (Peeters), 2, 1 Paper Electrophoresis of Proteins and Protein-Bound Substances in Clinical Investigations (Owen), I, 238 Parathyroid Function and Hyperparathyroidism, Biochemical Aspects of (Nordin), 4, 275... 

Vitamin Br, Absorption, Distribution, and Excretion, Physiology and Pathology of (Grasbeck), 3, 299 Vitamins, Microbiological Assay Methods for (Baker and Sobotka), 5, 173... 

Microbiological Assay Methods for Vitamins Herman Baker and Harry Sobotka... 

Several different techniques have been proposed for vitamin B12 determination, such as microbiological assay, spectrophotometry, chemiluminescence, atomic absorption spectrometry, capillary electrophoresis, and HPLC. 

Deficiencies of folic acid and vitamin B1 are relatively common. Whenever macrocytic anemia is present, evaluation of these two vitamins is necessary 10 determine the cause of the condition, The standard method of measuring folic acid has been the microbiological assay (Bailey et al.. 19821. which can be used to measure folic acid in serum, blood, tissues, and foods. Improved high performance liquid chromatography (HPLC) methods have... 

Kawasaki (68) briefly reviewed HPLC methods for determining total thiamine alone and in combination with riboflavin. Russell (44) provided a more detailed summary of HPLC methods, published between 1990 and 1994, for thiamine alone and in conjunction with other vitamins. Ball (45) reviewed selected HPLC analyses for thiamine in various foods, as well as other chemical and microbiological assays. 

Common HPLC detectors lack the sensitivity and selectivity to determine the low concentrations of the endogenous B,2 vitamers in foods. As a result, vitamin Bl2 method development for food samples has concentrated on ligand binding and microbiological assays no reviews of HPLC methods have been published. 

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... 

In certain health food literature, Spirulina, a blue-green algae, has been claimed to be a source of vitamin B12. It appears that this was based on the results obtained from the United States Pharmacopeia microbiological assay for vitamin B12. This assay uses Lactobacillus leichmannii as the test organism and it is known that this organism responds to some vitamin B12 analogs. Herbert and Drivas (H7) found that analogs of the vitamin accounted for more than 80% of what appeared to be vitamin B12. ... 

G3. Green, R., Newmark, P. A., Musso, A. M., and Mollin, D, L., The use of chicken serum for measurement of serum vitamin B12 concentration by radioisotope dilution Description of method and comparison with microbiological assay results. Br. J. Haematol. 27, 507-527 (1974). 

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