Chlorophyll adsorption

However, as shown by the curves in Figure 17, bleaching efficiency for Clay C does not attain maximum activity levels untU well after the surface area curve has peaked and started to decline. Note also that both clays achieve practically identical maxima in chlorophyll bleaching efficiencies (albeit requiring different acid dosages), but Clay C only achieves a maximum surface area of about 300 m /g, whereas Clay A achieves a maximum surface area of nearly 500 m /g. Clearly, surface area, per se, is not correlated with chlorophyll adsorption capacity. Similar curves (not shown) were obtained for carotene adsorption (12). 

Todd.J. F. J. (1991). Pure and Applied Chemistry (Vol. 63). 1541—1566. Tswett, M. (1906). Physical Chemical Studies on Chlorophyll Adsorptions. Berichte der Deutschen botanischen Gesellschaft, 24, 316-323. 

Tswett, M.S. (1906) Physical chemical studies on chlorophyll adsorption. Berichte der Deutschen botanischen Gesdlschafi, 24, 316-323 (as translated and excerpted in H.M. Leicester, Source Book in Chemistry 1900-1950, Cambridge, MA Harvard, 1968). 

Tswett, M. 1906. Physikalisch-Chemische Studien liber das Chlorophyll. Die Adsorption. (Physical-chemical studies of chlorophyll. Adsorption.) Berichte der Deutschen botanischen Gesellschaft, 24 316-326. 

During chlorophyll adsorption at the octane/water interface, the interfacial tension changes markedly. This fact was utilized in determining the surface excess of chlorophyll by the Gibbs equation. From the slope of the initial section of the isotherm,... 

Woodward s synthesis, 4, 416-419 Chlorophyll b, 4, 382 Chlorophyll c, 4, 382 Chlorophyll d, 4, 382 Chlorophylls, 4, 378 biosynthesis reviews, 1, 99 structure, 4, 370 substituents reactions, 4, 402 Chloroporphyrin e, 4, 404 Chloroprothixene pharmacology, 3, 942 Chloropyramine as antihistamine, 1, 177 Chloropyrifos synthesis, 2, 201 Chloropyrifos-ethyl as insecticide, 2, 516 Chloropyrifos-methyl as insecticide, 2, 516 Chloroquine, 1, 145 adsorption on nucleic acids, 1, 179 as antimalarial, 1, 173, 2, 517 Chloroquine, hydroxy-as antimalarial, 2, 517 Chlorosulfonyl isocyanate cycloaddition reactions... 

Eor the majority of foods, especially those containing high levels of chlorophyll, carotenoids, waxes or fats, a cleanup technique is usually used to minimize contamination of the analytical instruments, especially for GC. There are a number of cleanup techniques that can be employed based on partition, adsorption, ion exchange and size exclusion. 

M. Tswett. Adsorption Analyse und Chromatographische Methode Anwendung auf die Chemie des Chlorophylls. Ber. Deutschen Botan. Ges., 24(1906) 386. 

It is important to purify proanthocyanidins, particularly for determining their conversion yield. It is also advantageous to do so to eliminate extraneous material that might otherwise react with the proanthocyanidins. A combination of liquid-liquid extraction and adsorption chromatography is effective in removing impurities. The use of chloroform in liquid-liquid extraction is very effective in removing fat-soluble compounds such as carotenoids, chlorophyll, oils, and waxes. These compounds would be expected in leafy plant tissues (carotenoids and chlorophyll) as well as seeds and fruits (oils and waxes). Ethyl acetate is effective in the selective removal of flavan-3-ol monomers, which are also typically present with proanthocyanidins. 

Official quality parameters comprise acidity, peroxide value, halogenated solvents, ultraviolet adsorption and sensory assessment. In addition to these official parameters important roles and high values are attributed to the content of the chlorophyll and carotene pigments and phenol antioxidants, as well as to the correlated induction time value. The significance of olive oil quality parameters is explained in Table 2.1. The phenol content and the related induction period, defined as the delay in the commencement of oxidation in an oil , merits particular comment the longer the induction period, the better the oil. Resistance... 

Multilayers of sterols,3 chlorophyll,4 and proteins5 have also been built. Those of sterols show specific adsorptive powers for digitonin, according to the stereochemical configuration of the hydroxyl group those of chlorophyll showed no fluorescence, although the quantity deposited was sufficient to give marked fluorescence in solution. 

B.2.3.4. Other Methods to Remove Chlorophyll Derivatives Other approaches to the removal of chlorophyll derivatives compounds from canola oil than adsorption are known and are being practiced. Bergman (86) and Szemraj (87) described the use of concentrated phosphoric acid and vacuum drying of the oil to precipitate... 

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