Interaction of beta-cyclodextrin with bile acids and their competition with vitamins A and D3 as determined by 1H-NMR spectrometry.
The interaction of beta-cyclodextrin (beta-CD) with four bile acids, cholic, taurocholic, chenodeoxycholic and lithocholic, was demonstrated by proton-NMR spectroscopy. Lithocholic and chenodeoxycholic acids exhibit a stronger affinity for beta-CD than cholic and taurocholic acids. The affinity of bile acids for beta-CD increases in relation to their hydrophobicity. The competition between these bile acids and the lipophilic vitamins A and D3 in the formation of beta-CD inclusion complexes was studied. These vitamins compete with cholic and taurocholic acids whereas they do not with lithocholic and chenodeoxycholic acids. In the latter case all of the beta-CD present was consumed by the bile acids with the vitamins remaining free in the medium. The affinity of vitamins A and D3 for beta-CD is lower than that of the bile acids. Therefore, when lithocholic or chenodeoxycholic acids are present, the formation of beta-CD inclusion complexes with the vitamins does not occur. The results of this study suggest that depletion of lipophilic vitamins will not occur upon ingestion of beta-CD, thus providing further support for the safety and suitability of beta-CD as an ingredient in foods and orally administered drugs.
Comini
S
S
Laboratoire de Physiologie de la Nutrition, Université Paris Sud, Orsay, France.
Olivier
P
P
Riottot
M
M
Duhamel
D
D
D001647:Bile Acids and Salts / Q000378:metabolism*; D001667:Binding, Competitive; D002635:Chenodeoxycholic Acid / Q000378:metabolism; D002762:Cholecalciferol / Q000378:metabolism*; D019826:Cholic Acid; D002793:Cholic Acids / Q000378:metabolism; D003505:Cyclodextrins / Q000378:metabolism*; D006801:Humans; D008095:Lithocholic Acid / Q000378:metabolism; D009682:Magnetic Resonance Spectroscopy; D013656:Taurocholic Acid / Q000378:metabolism; D014801:Vitamin A / Q000378:metabolism*; D047392:beta-Cyclodextrins
D001647:Bile Acids and Salts; D002793:Cholic Acids; D003505:Cyclodextrins; D047392:beta-Cyclodextrins; D002635:Chenodeoxycholic Acid; D014801:Vitamin A; D002762:Cholecalciferol; D013656:Taurocholic Acid; D008095:Lithocholic Acid; D019826:Cholic Acid; C031215:betadex