Abstract

A simplified HPLC method for rapid determination of folates in yeast with ultraviolet and fluorescence detection without sample purification has been developed. By use of the column Aquasil C-18, specially designed for polar analytes, and gradient elution, it was possible to separate and determine five folate derivatives: tetrahydrofolate, 5-methyltetrahydrofolate, and 5-formyltetrahydrofolate with fluorescence detection, and 10-formylfolic acid and folic acid with ultraviolet detection. The sample preparation required only a small amount of dry yeast (25-50 mg) and included an extraction of folates by heat treatment and deconjugation of folate polyglutamates to monoglutamates with the use of rat serum conjugase. Validation involved investigation of matrix effects, determination of recovery by standard addition method, repeatability, and stability tests. The dominating folate forms in commercial dry baker's yeast were found to be tetrahydrafolate and 5-methyltetrahydrofolate with a total folate content of 2890 mu g/100 g (63.4 nmol/g). The simplicity of the method makes it suitable for folate screening studies of different yeast strains

Keywords

Folates; analysis; monoglutamates; yeast; food; deconjugation; HPLC; chromatography; validatopn

Published in

Journal of Agricultural and Food Chemistry
2005, Volume: 53, number: 7, pages: 2406-2411
Publisher: AMER CHEMICAL SOC

SLU Authors

• Patring, Johan

  • Department of Molecular Sciences, Swedish University of Agricultural Sciences
    

• Jastrebova, Jelena

  • Department of Molecular Sciences, Swedish University of Agricultural Sciences
    

• Jägerstad, Margaretha

  • Department of Molecular Sciences, Swedish University of Agricultural Sciences
    

UKÄ Subject classification

Food Science


Publication identifier

DOI: https://doi.org/10.1021/jf048083g

Permanent link to this page (URI)

https://res.slu.se/id/publ/7554