Xanthophyll pigments

The most common of the xanthophyll pigments, it is present in all green leaves, in blossoms and in various animal sources. It crystallizes in violet prisms with one molecule of methanol m.p. I93 C, soluble in organic solvents giving yellow solutions, li is related to a-carolene in the same way as zeaxanlhin is to /1-carolene. 

One of the xanthophyll pigments present in various leaves, seeds and fruits, and in yolk of egg. It is often present in company with lutein, of which it is an isomer. It bears the same relation to -carotene as lutein does to a-caro tene. 

Milanowska, J., A. Polit, Z. Wasylewski, and W.I. Gruszecki. 2003. Interaction of isomeric forms of xanthophyll pigment zeaxanthin with dipalmitoylphosphatidylcholine studied in monomolecular layers. J. Photochem. Photobiol. B Biol. 72 1-9. 

Sujak, A., W. Okulski, and W.I. Gruszecki. 2000. Organisation of xanthophyll pigments lutein and zeaxanthin in lipid membranes formed with dipalmitoylphosphatidylcholine. Biochim. Biophys. Acta 1509 255-263. 

Sujak, A., P. Mazurek, and W. I. Gruszecki. 2002. Xanthophyll pigments lutein and zeaxanthin in lipid multibilayers formed with dimyristoylphosphatidylcholine. J. Photochem. Photobiol. B 68 39 44. 

DIFFERENCE IN XANTHOPHYLL PIGMENT CONCENTRATIONS ALONG A SERIES OF NUMBER 2 LEAF BLADES (MEAN S.E.M n = 5). 

Maize gluten meal is not a very suitable feed for poultry since it is of relatively low palatability and being very deficient in lysine has an imbalanced AA profile. However, it can be incorporated in broiler and layer diets as a source of natural yellow pigment since it is rich in xanthophyll pigments (up to 300mg/kg). Maize gluten meal may no longer be available or economic for feed use as it is used extensively as a natural weed-killer in horticulture. 

The main pigments of Phaeocystis antarctica were chlorophyll a, chlorophyll c + 2, fucoxanthins, diadinoxanthin and diatoxanthin. The ratio of the photoprotective xanthophyll pigments diadi-no- and diatoxanthin to chlorophyll a was 0.229 in... 

Xanthophyll pigments in the light harvesting complex (LHCII) are primarily bound in the -trans form (Kiihlbrandt et al, 1994). This does not mean that these xanthophyll pigments do not undergo triplet reactions. Triplets have been found in all major xanthophylls in plants, including lutein, neoxanthin and violaxanthin and xanthophyll triplets have been observed in isolated LHC (Peterman et al, 1995). 

Polar carotenoids rigidify the lipidmembrane in its fluid state by restrictions to different kind of molecular motions oflipid. This type ofinteraction influences mechanical properties of the membrane (reinforcement) and is consistent with the idea of a xanthophyll pigment as a molecular rivet to the membrane. 

Sielewiesiuk J, Matula M and Gruszecki WI (1997) Photooxidation of chlorophyll a in digalactosyldiacylglycerol liposomes containing xanthophyll pigments Indication of a special photoprotective ability of zeaxanthin. Cell Mol Biol Lett 2 59-68... 

Tswett discovered that leaves contained two distinct green chlorophyll pigments and three or four yellow (xanthophylls) pigments. The accompanying figure depicts the separation of pigments achieved hy Tswett using carhon disulfide as solvent. Once the experiment was completed, these layers were removed individually from the column with a spatula and washed with solvent or eluted selectively with solvents. 

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