Absorption 3-carotene

Mantini A R, Marzocchi M P and Smulevich G 1989 Raman excitation profiles and second-derivative absorption spectra of beta-carotene J. Chem. Phys. 91 85-91... 

WANG X D (1994) Review absorption and metabolism of beta-carotene , JAm Coll Nutr, 13, 314-25. 

VAN VLIET T, SCHREURS w H and VAN DEN BERG H (1995) Intestinal beta-carotene absorption and cleavage in men response to beta-carotene and retinyl esters in the triglyceride-rich lipoprotein fi action after a single oral dose of beta-carotene. Am J Clin Nutr 62(1) 110-16. 

In colorants, the spectral absorption pattern and the extinction coefficient are determined by the chromophore and rarely by side groups of the molecule, p-carotene and zeaxanthin contain the same chromophore but their molecular masses... 

The maximum spectrometric absorption of lutein (C40H56O2, mol wt 568.9, xanthophyll, (3R,3.S,6.R)-p,8-carotene-3,3.-diol) is found between 453 and 481 nm. Its solubihty in ethanol is greater than that of the carotenoids. It is somewhat less sensitive to oxidation and heat degradation than P-carotene. It contributes yellow color." ... 

In contrast with the hydrocarbon carotenes primarily located in the cores of the CM particles, xanthophylls are present at the surfaces of the CM particles, making their exchanges with other plasma lipoproteins easier." Therefore, if some exchanges occur between lipoproteins, AUC (or absorption) values of the newly absorbed compound in the TRL fraction will be underestimated. Based on all these considerations, the present approach is more appropriate to determine the relative bioavailability of a compound derived from various treatments within one snbject and/or within one study. 

Using high performance liquid chromatography plus GC-MS and a compart-mental model, the absorption of p-carotene was estimated as 22% (17.8% as intact P Carotene and 4.2% as retinoids) after ingestion of a single high dose of p-carotene-d8 (40 mg) in oil by one adult subject. This value was close to the 9 to 17% values obtained in earlier human lymph cannulation studies using radioisotopes. ... 

In contrast to previous in vivo models, this in vitro model provides the possibility of dissociating experimentally two important processes of intestinal absorption cellular uptake and secretion. Under conditions mimicking the postprandial state (taurocholate/oleic acid supplementation), differentiated Caco-2 cells were able to (1) take up carotenoids at the apical sides and incorporate them into CMs and (2) secrete them at the basolateral sides associated with CM fractions. Using this approach, the extent of absorption of P-carotene through Caco-2 cell monolayers after 16 hr of incubation was 11.2%, a value falling within the in vivo range (9 to 22%). ° - Of the total amount of P-carotene secreted, 78% was associated with the two CM fractions and 10% with the VLDL fraction. ... 

Caco-2 cells and ezetimibe, a potent inhibitor of chloresterol absorption in humans, it was reported that (1) carotenoid transport was inhibited by ezetimibe up to 50% and the extent of that inhibition diminished with increasing polarity of the carotenoid molecule, (2) the inhibitory effects of ezetimibe and the antibody against SR-BI on P-carotene transport were additive, and (3) ezetimibe may interact physically with cholesterol transporters as previously suggested - and also down-regulate the gene expression of three surface receptors, SR-BI, NPCILI, and ABCAl. 

Kostic, D., White, W.S., and Olson, J.A., Intestinal absorption, serum clearance, and interactions between lutein and 3-carotene when administered to human adults in separate or combined oral doses. Am. J. Clin. Nutr, 62, 604, 1995. 

Gaziano, J.M. et al.. Discrimination in absorption or transport of (3-carotene isomers after oral supplementation with either all-trans or 9-cis (3-carotene, Am. J. Clin. Nutr., 61, 1248, 1995. 

Jayaranjan, P., Reddy, J.P. and Mohanram, M., Effect of dietary fat on absorption of (3-carotene from green leafy vegetables in children, Indian J. Med. Res., 70, 53, 1980. 

Hollander, D. and Ruble, P.E., P-Carotene intestinal absorption bile, fatty acid, pH, and flow rate effects on transport, Am. J. Physiol, 235, E686, 1978. 

Van Bennekum, A. et al.. Class B scavenger receptor-mediated intestinal absorption of dietary P-carotene and cholesterol, Biochem., 44, 4517, 2005. 

The food matrix including its fiber and lipid content and concentrations of other carotenoids in the diet may influence the extent of absorption of carotenoid compounds. The relative absorption of lutein from a mixed vegetable diet was lower than from a diet containing pure lutein. A mixed preparation of lutein and zeaxanthin did not influence the absorption of P-carotene. 

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