Leaf pigment

Chromatography is based upon the selective adsorption from solution on the active surface of certain finely divided solids. Closely related substances exhibit different powers of adsorption, so that separations, which are extremely difficult by ordinary chemical methods, may be effected by this means. When, for example, a solution of leaf pigments... 

WETZEL c M and RODERMEL s R (1998) Regulation of phytoene desaturase expression is independent of leaf pigment content in Arabidopsis thaliana , Plant Mol Biol, 37, 1045-53. 

Predict what will happen when a mixture of leaf pigments is placed on a piece of paper and a solvent is allowed to move through the paper, moving the pigment with it. 

Gamon, J.A. and Surfus, J.S., Assessing leaf pigment content and activity with a reflectometer. New Phytol, 143, 105, 1999. 

Oren-Shamir, M. and Levi-Nissim, A., Temperature effects on the leaf pigmentation of Cotinus coggygria Royal Purple , J. Hortic. ScL, 72, 425, 1997. 

Leafing and Nonleafing. Leafing pigments float on the surface of paint or printing ink films as a result of high interfacial tension. They form a coherent surface film whose reflective properties depend on the particle fineness. Stearic acid is the lubricant usually used in the manufacture of these products. 

A similar result is accomplished by using as one phase a solid powder or fine "beads" packed in a vertical column or spread in a thin layer on a plate of glass. The methods are usually referred to as chromatography, a term proposed by Tswett to describe separation of materials by color. In 1903 Tswett passed solutions of plant leaf pigments (chlorophylls and carotenes) in nonpolar solvents such as hexane through columns of alumina and of various other adsorbents and observed separation of colored bands which moved down the column as more solvent was passed through. Individual... 

Leafing pigments float on the surface of the wet film, orienting themselves parallel to the surface and thereby forming a dense metallic layer on top of the coating. This layer has a high reflectivity and provides excellent barrier protection of the film (resin). 

Non-leafing pigments on the other hand are perfectly wetted in the binder and therefore oriented more or less parallel to the substrate on the bottom of the wet film. The cured films are rub-resistant with an excellent adhesion to following clear coats. The pigmented film can easily be tinted with transparent color pigments or dyestuffs, thereby creating the typical polychromatic metallic effect . 

Chlorophyll a Is one of several leaf pigments. It absorbs red and blue wavelengths strongly. Thus, leaves containing large amounts of chlorophyll a appear green. We can use the strong absorption at 663 nm... 

Schlotzhauer, W.S. and I. Schmeltz Non-aUcaloidal bases from pyrolysis of tobacco leaf pigment at the approximate burn temperature of a cigarette Tob. Sci. 

Arsenyan, E. and K. Paskaleva-Tomov Composition of leaf pigments in Virginia bright tobacco and relation with... 

Phaeophorbide has been converted into aetioporphyrin 28, which confirmed the structural relationship between blood and leaf pigments (H. Fischer 1929-40). 

The leaf pigments of Coleus (Labiatae) species continue to be the source of highly oxidized diterpenoids. A group of eleven coleons and royleanones including carnosolone (36) were obtained " from C carnosus and coleon X (37) and the unusual cw-butadiene coleon Z (38) were obtained from Solenostemon... 

Cold acclimation caused significant changes in the leaf pigment composition, as seen from the carotenoid/chlorophyll ratios given in Fig. 

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