Relative bioavailability of deuterium-labeled monoglutamyl and hexaglutamyl folates in human subjects

Journal Article · Fri Mar 01 00:00:00 EST 1991 · American Journal of Clinical Nutrition; (USA)

OSTI ID:5945422

Gregory, III, J F; Bhandari, S D; Bailey, L B; Toth, J P; Baumgartner, T G; Cerda, J J ^[1]

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1. Univ. of Florida, Gainesville (USA)

The bioavailability of orally administered mono- and polyglutamyl folates was examined in humans by using stable-isotope methods. (3',5'-2H2)Folic acid (d2-FA) and (3',5'-2H2)pteroylhexaglutamate (d2-PteGlu6) were prepared for oral administration and (glu-2H4)folic acid (d4-FA) was prepared for intravenous (iv) injection. In two trials, adult males (n = 7) on a folate saturation regimen (2 mg/d) were given a single 677-nmol oral dose of either d2-FA or d2-PteGlu6 in apple juice along with an iv injection of 502 nmol d4-FA as a control. Urine was collected for 48 h and the isotope labeling of urinary folates determined by mass spectrometry. The excretion ratio of urinary folates (% of d2-folate dose/% of d4-folate dose) resulting from oral d2-FA and iv d4-FA was 1.45 +/- 0.10 (mean +/- SEM) whereas the ratio for oral d2-PteGlu6 and iv d4-FA was 0.67 +/- 0.04. These results indicate that the d2-PteGlu6 is available to humans as a source of folate although its bioavailability is substantially less than that of d2-FA under these conditions.

• OSTI ID: 5945422
• Journal Information: American Journal of Clinical Nutrition; (USA), Vol. 53:3; ISSN 0002-9165
• Country of Publication: United States
• Language: English

Related Subjects

59 BASIC BIOLOGICAL SCIENCES
FOLIC ACID
BIOLOGICAL AVAILABILITY
DEUTERIUM
MAN
MASS SPECTROSCOPY
METABOLISM
ORAL ADMINISTRATION
REGRESSION ANALYSIS
TRACER TECHNIQUES
URINE
AMINO ACIDS
ANIMALS
AROMATICS
AZAARENES
BIOLOGICAL MATERIALS
BIOLOGICAL WASTES
BODY FLUIDS
CARBOXYLIC ACIDS
DRUGS
HEMATINICS
HEMATOLOGIC AGENTS
HETEROCYCLIC COMPOUNDS
HYDROGEN ISOTOPES
HYDROXY COMPOUNDS
ISOTOPE APPLICATIONS
ISOTOPES
LIGHT NUCLEI
MAMMALS
MATERIALS
MATHEMATICS
NUCLEI
ODD-ODD NUCLEI
ORGANIC ACIDS
ORGANIC COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
PRIMATES
PTERIDINES
SPECTROSCOPY
STABLE ISOTOPES
STATISTICS
VERTEBRATES
VITAMIN B GROUP
VITAMINS
WASTES
550501* - Metabolism- Tracer Techniques