title: Relative bioavailability of 13C5-folic acid in pectin-coated folate fortified rice in humans using stable isotope techniques.
abstract: The aim of the study was to measure the relative bioavailability of labeled pteroylglutamic acid (13C5-PteGlu) from a pectin-coated fortified rice in vivo to measure any effect of the edible coating on folic acid bioavailability.
  
  
  
  Healthy volunteers (N=26) aged 18-39 years received three test meals in three randomized short-term cross-over trials: Trial 1: aqueous 400 μg 13C5-PteGlu, Trial 2: 200 g cooked white rice+400 μg 13C5-PteGlu,Trial 3: 200 g fortified cooked white rice with pectin-coated premix containing 400 μg 13C5-PteGlu. Blood samples were drawn at 0,1,2,5 and 8 h postprandial. The concentration of 13C5-5 methyl-tetrahydrofolate appearing in plasma was quantified using high performance liquid chromatography-mass spectrometry (MS)/MS. For 24 h before baseline estimation and during the area under the curve (AUC) study, the subjects were placed on a low folate diet (∼100 μg/day). The relative bioavailability of the folic acid following Trial 3 was measured by comparing the 13C5-5 methyl-tetrahydrofuran (THF) AUC with Trials 1 and 2.
  
  
  
  The bioavailability of folic acid in a pectin-coated rice premix was 68.7% (range 47-105) and 86.5% (range 65-115) in uncoated fortified rice relative to aqueous folic acid.
  
  
  
  This study is the first demonstration of the bioavailability of folate in pectin-coated fortified rice in humans.
authors.affiliation: Food Science and Technology, School of Chemical Engineering, UNSW Australia, Sydney, New South Wales, Australia.
authors.forename: A
authors.initials: A
authors.lastname: de Ambrosis
authors.affiliation: Food Science and Technology, School of Chemical Engineering, UNSW Australia, Sydney, New South Wales, Australia.
authors.forename: S
authors.initials: S
authors.lastname: Vishnumohan
authors.affiliation: Food Science and Technology, School of Chemical Engineering, UNSW Australia, Sydney, New South Wales, Australia.
authors.forename: J
authors.initials: J
authors.lastname: Paterson
authors.affiliation: Drug Health Services, Sydney South West Area Health Service, Discipline of Addiction Medicine, Faculty of Medicine, Royal Prince Alfred Hospital, Sydney, New South Wales, Australia.
authors.forename: P
authors.initials: P
authors.lastname: Haber
authors.affiliation: Food Science and Technology, School of Chemical Engineering, UNSW Australia, Sydney, New South Wales, Australia.
authors.forename: J
authors.initials: J
authors.lastname: Arcot
mesh_terms: D000293:Adolescent; D000328:Adult; D019540:Area Under Curve; D001682:Biological Availability; D018592:Cross-Over Studies; D005260:Female; D005492:Folic Acid / Q000031:analogs & derivatives / Q000493:pharmacokinetics*; D005527:Food, Fortified; D064368:Healthy Volunteers; D006801:Humans; D007553:Isotope Labeling / Q000379:methods; D008297:Male; D012275:Oryza; D010368:Pectins; D013057:Spectrum Analysis / Q000379:methods; D013763:Tetrahydrofolates / Q000097:blood*; D014803:Vitamin B Complex / Q000493:pharmacokinetics*; D055815:Young Adult
chemical_list: D013763:Tetrahydrofolates; D014803:Vitamin B Complex; D010368:Pectins; D005492:Folic Acid; C005984:5-methyltetrahydrofolate