DIFFERENTIAL ASSAYS OF FOLIC ACID IN ANIMAL TISSUES
1972; Elsevier BV; Linguagem: Inglês
10.1016/b978-0-12-403502-7.50043-0
AutoresO. D. Bird, Virginia Mims McGlohon,
Tópico(s)Folate and B Vitamins Research
ResumoThis chapter explains the evolution of folate assay procedures and use of combined criteria for differential assays of folates. The conjugase concept arose from ensuing experimentation in which various animal tissues were incubated with yeast extracts containing polyglutamate conjugates of folic acid but no endogenous enzyme to split them. In a study described in the chapter, a small amount of homogenized animal tissue incubated with a large amount of yeast extract led to a great increase in activity toward the folate assay organisms. A small sample of an extract of the tissue under study was adsorbed on the column from a buffer solution containing ascorbate. A standard amount of this same buffer was placed above the adsorbent and to this was added dropwise a phosphate–ascorbate buffer, pH 7.0, so as to gradually build up the phosphate content of the effluent as it ran through.
Referência(s)