Determination of five folate monoglutamates in rodent diets.
A method for the quantitative determination of folates in rodent diets is very important for correct interpretation of folate intake during feeding trials, given the possible discrepancy between the actual folate concentration in the diet and that mentioned on the product sheet. Liquid chromatography tandem-mass spectrometry is the method of choice to differentiate and quantify the individual folate species present. This discrepancy may be accounted for by, e.g., inaccurate folic acid supplementation and/or the presence of endogenous reduced and substituted folates. We developed a method, validated based on FDA guidelines, that allows the measurement of added and endogenous folates by quantitative determination of 5 folate monoglutamates with linear ranges from 8 μg to 2 mg/kg feed. This information, combined with feed intake data, allows insight into the actual folate intake in animal feeding studies. The relevance of this method was illustrated by the analysis of several feed samples of varying composition, by the investigation of the effect of casein incorporation, and by evaluating the variability of the folate content between pellets and production batches.
Laboratory of Toxicology, Ghent University , Ottergemsesteenweg 460, B-9000 Gent, Belgium.
Filip
F
Kiekens
Laboratory of Toxicology, Ghent University , Ottergemsesteenweg 460, B-9000 Gent, Belgium.
Jeroen Van
JV
Daele
Laboratory of Functional Plant Biology, Department of Physiology, Ghent University , K.L. Ledeganckstraat 35, B-9000 Gent, Belgium.
Dieter
D
Blancquaert
Laboratory of Functional Plant Biology, Department of Physiology, Ghent University , K.L. Ledeganckstraat 35, B-9000 Gent, Belgium.
Dominique
D
Van Der Straeten
Laboratory of Toxicology, Ghent University , Ottergemsesteenweg 460, B-9000 Gent, Belgium.
Willy E
WE
Lambert
Laboratory of Toxicology, Ghent University , Ottergemsesteenweg 460, B-9000 Gent, Belgium.
Christophe P
CP
Stove
D000821:Animal Feed / Q000032:analysis*; D000818:Animals; D002623:Chemistry Techniques, Analytical / Q000379:methods*; D005492:Folic Acid / Q000031:analogs & derivatives* / Q000032:analysis; D005971:Glutamates / Q000032:analysis*; D012377:Rodentia
D005971:Glutamates; C083563:folate monoglutamate; D005492:Folic Acid
folate; liquid chromatography; mass spectrometry; rodent diet