Fucoxanthins

Most of this amount is in the form of fucoxanthin in various algae and in the three main carotenoids of green leaves lutein, violaxanthin, and neoxanthin. Others produced in much smaller amounts but found widely are p-carotene and zeaxanthin. The other pigments found in certain plants are lycopene and capsanthin (Figure 2.2.1). Colorant preparations have been made from all of these compounds and obviously the composition of a colorant extract reflects the profile of the starting material. Carotenoids are probably the best known of the food colorants derived from natural sources. ... 

Fucoxanthin, lutein, neoxanthin, violaxanthin, and zeaxanthin are the most common xanthophylls on our planet. They are found in the photosynthetic machinery of algae (fucoxanthin) and higher plants (Figure 7.1). Interestingly, lutein and zeaxanthin have also been found in the retina of humans and some primates (Khachik et al., 1997 Landrum and Bone, 2001). It is likely that these carotenoids possess some universal photophysical properties essential for both photosynthesis and vision (Britton, 1995). 

Polivka, T., M. Pellnor, E. Melo, T. Pascher, V. Sundstrom, A. Osuka, and K. R. Naqvi. 2007. Polarity-tuned energy transfer efficiency in artificial light-harvesting antennae containing carbonyl carotenoids peridi-nin and fucoxanthin. J. Phys. Chem. C 110 467 -76. 

Recently, fucoxanthin has been shown to inhibit the proliferation of human colon cancer cells by a mechanism involving an up-regulation of p21WAFl/Cipl (Das et al., 2005). 

Das, S.K., Hashimoto, T., Shimizu, K., and Kanazawa, K. 2005. Fucoxanthin induces cell cycle arrest at GO/ Gl phase in human colon carcinoma cells through up-regulation of p21WAFl/Cipl. Biochim Biophys Acta 30 328-335. 

Hosokawa, M., Kudo, M., Maeda, H., Kohno, H., Tanaka, T., and Miyashita, K. 2004. Fucoxanthin induces apoptosis and enhances the antiproliferative effect of the PPARgamma ligand, troglitazone, on colon cancer cells. Biochim Biophys Acta 1675 113-119. 

Scheme 4 Structures of apo-fucoxanthinoids isolated from the diatom Phaeodactylum tricornutum. 11 apo-lO -fucoxanthinal, 12 apo-12 -fucoxanthinal, 13 apo-12-fucoxanthinal, 14 apo-13 -fucoxanthinone...

Maeda H, Hosokawa M, Sashima T, Funayama K and Miyashita K. 2005. Fucoxanthin from edible seaweed, Undariapinnatifida, shows antiobesity effect through UCP1 expression in white adipose tissues. Biochem Biophys Res Commun 332(2) 392-397. 

Carotenoids are probably the best known of the colorants and certainly the largest group of pigments produced in nature with an annual production estimated at 100,000,000 tons. Most of this is fucoxanthin produced by algae in the ocean and the three main pigments, lutein, violaxanthin and neoxanthin in green leaves.10 Over 600 carotenoid compounds have been reported. 

Scheme 18.2 Structure of the allenic carotinoids fucoxanthin (5) and peridinin (6).

Chlorophyll-a Pheophytin-a Pyropheophitin- a Pheophorbide-a Pyropheophorobide-a Isofucoxanthin-dehydrate Fucoxanthin dehydrate Fucoxanthin-hemiketal Isofucoxanthin dehydrate pheophorbide a ester Isofucoxanthin dehydrate pheophorbide a ester Isofucoxanthin dehydrate pyropheophorbide a ester 23.5 26.4 28.1 5.0 6.9 10.7 12.0 6.4 24.4 22.9 25.4... 

Fig. 2.124. HPLC absorbance chromatograms of phytoplankton samples collected from the study site on 24 November 2000 (a), 25 November 2000 (b) and 1 December 2000 (c). Peak identification 1 = chlorophyll-a 2 = chlorophyll-b 3 = chlorophyll-c2 4 = peridin 5 = fucoxanthin 6 = neoxanthin 7 = 19 -hexanoylfucoxanthin 8 = diadinoxanthin 9 = alloxanthin 10 = lutein 11 = zeaxanthin 12 = /1-carotene. Reprinted with permission from C. K. Wong et al. [282],...

Per = peridinin But-fuco = 19 -butanoyloxyfucoxanthin fuco = fucoxanthin Hex-fuco = 19 -hexanoyloxyfucoxanthin Neo = neoxanthin Viol = violaxanthin Alio = alloxanthin Zea = zeaxanthin Chi b = chlorophyll-b DV chi a = divinyl chlorophyll-a. 

Fig. 2.125. HPLC chromatograms generated at 440 nm. Pure cultures (a) Synechococcus elongatus, (b) 2 micron picosphere , (c) Cyclotella choctawatcheena. Phytoplankton field communities (d) Twin Key Basin, (e) Rabbit Key Basin, (f) Sandy Key Basin, ft = /1-carotene, Z = zeaxanthin, a = chlorophyll-a, N = myxoxanthophyll, E = echinenone, c,/c2 = chlorophylls-Cj/c2, F = fucoxanthin, Col = unknown carotenol, Cone = unknown carotenone, D = diadinoxan-thin, P = peridin. Reprinted with permission from J. W. Louda et al. [283].

Carotenoids Peridinin Fucoxanthin 19 -butanoyloxyfucoxanthin 19 -hexanoyloxyfucoxanthin Alloxan thin Prasinoxanthin Lutein Zeaxanthin Dinoflagellates Diatoms Pelagophytes Haptophytes Cryptophytes Prasinophytes Chlorophytes Cyanobacteria, chlorophytes... 

Diatoms Fucoxanthin containing phytoplankton characterized by the presence of a silica-impregnated cell wall. 

Structure of various terpenoid piant pigments (a) fucoxanthin, (b) (i-carotene, and (c) xanthophyll. OAc = acetate. 

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