Carotenoid lutein

Dwyer, J.H. et al., Oxygenated carotenoid lutein and progression of early atherosclerosis the Los Angeles atherosclerosis study, Circulation, 103, 292, 2001. 

Castelli, F., S. Caruso, and N. Giuffrida. 1999. Different effects of two structurally similar carotenoids, lutein and beta-carotene, on the thermotropic behaviour of phosphatidylcholine liposomes. Calorimetric evidence of their hindered transport through biomembranes. Thermochim. Acta 327 125-131. 

Carotenoids are also present in animals, including humans, where they are selectively absorbed from diet (Furr and Clark 1997). Because of their hydrophobic nature, carotenoids are located either in the lipid bilayer portion of membranes or form complexes with specific proteins, usually associated with membranes. In animals and humans, dietary carotenoids are transported in blood plasma as complexes with lipoproteins (Krinsky et al. 1958, Tso 1981) and accumulate in various organs and tissues (Parker 1989, Kaplan et al. 1990, Tanumihardjo et al. 1990, Schmitz et al. 1991, Khachik et al. 1998, Hata et al. 2000). The highest concentration of carotenoids can be found in the eye retina of primates. In the retina of the human eye, where two dipolar carotenoids, lutein and zeaxan-thin, selectively accumulate from blood plasma, this concentration can reach as high as 0.1-1.0mM (Snodderly et al. 1984, Landrum et al. 1999). It has been shown that in the retina, carotenoids are associated with lipid bilayer membranes (Sommerburg et al. 1999, Rapp et al. 2000) although, some macular carotenoids may be connected to specific membrane-bound proteins (Bernstein et al. 1997, Bhosale et al. 2004). 

Afzal, A. and M. Afzal (2008). Photoprotective carotenoids lutein and zeaxanthin Their role in AMD. Curr. Nutr. Food Sci. 4(2) 127-134. 

Kvansakul, J., M. Rodriguez-Carmona et al. (2006). Supplementation with the carotenoids lutein and zeaxanthin improves human visual performance. Ophthal. Physiol. Opt. 26(4) 362-371. 

Shao, A. and J. N. Hathcock (2006). Risk assessment for the carotenoids lutein and lycopene. Regul. Toxicol. Pharmacol. 45(3) 289-298. 

The most photosensitive part of the coleoptile with respect to phototropism is the apical 50 qm-zone. The first millimeter of the tip is 160 times more sensitive than the second, and the second millimeter 1,800 times more sensitive than the third 108h In 1937, Bunning29 showed by microchemical method that there is a high concentration of carotenoid (lutein) below the tip of the avena coleoptile, from 250 jum to 2 mm below this point and just in the extreme tip no carotenoid is found. This calls in question whether the enormous local differences in sensitivity can solely be caused by corresponding different absorption gradients. This doubt is further substantiated by the fact, that carotenoid deficient mutants (containing 5 to 10% of the normal siblings) show normal phototropic sensitivity. 

Kim JH, Na HJ, Kim CK, Kim JY, Ha KS, Lee H, Chung HT, Kwon HJ, Kwon YG and Kim YM. 2008. The non-provitamin A carotenoid, lutein, inhibits NF-KB-dependent gene expression through redox-based regulation of the phosphatidylinositol 3-kinase/PTEN/Akt and NF-KB-inducing kinase pathways role of H2O2 in NF-kB activation. Free Radic Biol Med 45(6) 885-896. 

Legally, carotenoids are divided between two E numbers. El60 covers the carotenoid hydrocarbons P-carotene, lycopene and paprika as well as the apo-carotenoids, e.g. bixin. E161 covers the xanthophylls and the carotenoids lutein, astaxanthin and canthaxanthin. 

Reversed-phase liquid chromatography shape-recognition processes are distinctly limited to describe the enhanced separation of geometric isomers or structurally related compounds that result primarily from the differences between molecular shapes rather than from additional interactions within the stationary-phase and/or silica support. For example, residual silanol activity of the base silica on nonend-capped polymeric Cis phases was found to enhance the separation of the polar carotenoids lutein and zeaxanthin [29]. In contrast, the separations of both the nonpolar carotenoid probes (a- and P-carotene and lycopene) and the SRM 869 column test mixture on endcapped and nonendcapped polymeric Cig phases exhibited no appreciable difference in retention. The nonpolar probes are subject to shape-selective interactions with the alkyl component of the stationary-phase (irrespective of endcapping), whereas the polar carotenoids containing hydroxyl moieties are subject to an additional level of retentive interactions via H-bonding with the surface silanols. Therefore, a direct comparison between the retention behavior of nonpolar and polar carotenoid solutes of similar shape and size that vary by the addition of polar substituents (e.g., dl-trans P-carotene vs. dll-trans P-cryptoxanthin) may not always be appropriate in the context of shape selectivity. 

Mein, J.R. Dolnikowski, G.G. Ernst, H. Russell, R.M. Wang, X.D. 2011. Enzymatic formation of apo-carotenoids from the xanthophyll carotenoids lutein, zeaxanthin and P-cyryptoxanthin by ferret carotene-9, lO -monooxygenase. Arch. Biochem. Biophys. 506 109-121. 

A concern has been raised that phytosterol doses that are effective for cholesterol reduction may impair the absorption and lower blood concentrations of fat-soluble vitamins and antioxidants. A number of studies showed that phytosterols had no effect on plasma concentrations of vitamin D, retinol, or plasma-lipid-standardized alpha-tocopherol. Moreover, the reports of the effect of phytosterols on concentrations of blood carotenoids (lutein, lycopene, and alpha-carotene) are controversial. There seems to be general agreement that phytosterol doses >1 g/d significantly decrease LDL-C standardized beta-carotene concentrations however, it remains to be determined whether a reported 15-20% reduction in beta-carotene due to phytosterol supplementation is associated with adverse health effects. Noakes et al. found that consumption of one or more carotenoid-rich vegetable or fruit servings a day was sufficient to prevent lowering of plasma carotenoid concentrations in 46 subjects with hypercholesterolemia treated with 2.3 g of either sterol or stanol esters. 

No carotenoids were detected in tissues of animals sacrificed after 6 weeks. However, as shown in Table 10.4, after 24 weeks, nearly all carotenoids (lutein, zeaxanthin, lycopene, y-carotene, -carotene, a-carotene, P-carotene, phytofluene, phytoene) were bioavailable in colon and liver of the animals that received MCM. A typical HPLC profile of carotenoids in a pooled extract from mouse liver is shown in Figure 10.2. The major carotenoids in brain were lycopene, lutein, and P-carotene. Carotene predominated in the breast tissues, while lutein, lycopene, y-carotene, and a-carotene were detected in low concentrations. Carotenoids were not detected in tissues of the mice on WD without MCM. 

Chapter 12 Photosystem-ll Light-Harvesting Complexes II. C. The Carotenoid Lutein... 

Bishop NI (1996) The beta, epsilon-carotenoid, lutein, is specifically required for the formation of the ohgomeric forms of the light harvesting complex in the green alga, Scenedesmus obliquus. J Photochem and Photobiol 36 279-283... 

The role of the macular carotenoids lutein (25) and zeaxanthin (15) in age-related macular degeneration has also been given much attention [63,64],... 

Chlamydomonas reinhardtii double mutant npq2/lorl lacks the P,e-carotenoids lutein and loroxanthin as well as all P,P-epoxycarotenoids derived from zeaxanthin (e g. violaxanthin and neoxanthin). Thus, the only carotenoids present in the thylakoid membranes of the npq2/lorl cells are P-carotene and zeaxanthin. The effect of these mutations and the lack of specific xanthophylls on the Chi antenna size of the photosystems was investigated [16]. In cells of the mutant strain, the Chi antenna size of PSII was substantially smaller than that of the wild type (Table 1). In contrast, the Chi antenna size of PSI was not truncated in the mutant. This analysis showed that absence of lutein, violaxanthin and neoxanthin specifically caused a smaller functional Chi antenna size for PSII but not for that of PSI. Thus, xanthophyll-bios5mthesis genes, such as lycopene e-cyclase and zeaxanthin epoxidase may be targets for a truncated Chi antenna size in PSII. 

Two essential carotenoids, lutein and zeaxanthin, play an important role in the visual process. For the treatment of age-related macular degeneration (AMD), knowledge of the isomeric composition within the macula is of particular interest [7], Full assignment of isomeric configuration is possible by the registration of two-dimensional proton-proton correlated NMR spectra. Figure 7-7 shows, as an example, the COSY stopped-flow NMR spectrum of all-trans zeaxanthin isolated from ox retina. 

Shanmugam, S., Baskaran, R., Balakrishnan, P., Thapa, P., Yong, C.S., Yoo, B.K., 2011. Solid self-nanoemulsifying drug delivery system (S-SNEDDS) containing phosphatidylcholine for enhanced bioavailability of highly lipophilic bioactive carotenoid lutein. Eur. J. Pharm. Biopharm. 79, 250—257. 

A diverse array of sources and preparative procedures are available to obtain organic carotenoids. - Lutein may be extracted from the petals of the Mexican marigold (Tagetes erecta) (Fig. 7.32). [69] Since xanthophyils occur in Nature mostly as esters, and while the free alcohol form is advantageous for many applications, the extraction process with a hydrocarbon is often followed by a hydrolytic step. [63]... 

Fig. 3 shows the effect of increasing concentrations of SAN 6706 on the relative proportions of the different carotenoids. Lutein + zeaxanthin remained fairly constant at about half the total carotenoid, whilst neoxanthin and violaxanthin decreased and 6-carotene increased. It is noteworthy that neoxanthin (an allenic trihydroxy carotenoid) and violaxanthin (a dihydroxy, diepoxy carotenoid) are the most highly derivatised of the compounds considered. Thus it appears that the effects of the herbicide on the inhibition of desaturation has the most pronounced effects on those compounds which involve the largest number of biosynthetic reactions. 

Palombo R, Fabrizi G., Ruocco V., Fliihr J., Roberts R., and Moiganti R. 2007. Beneficial long-term effects of combined oral/topical antioxidant treatment with carotenoids lutein and zeaxanthin on human skin A donble-bhnded, placebo-controUed study in humans. Skin Pharmacology and Physiology 20 199-210. 

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