Violaxanthine orange

Fig. 2.17. Saponified carotenoids in orange juice. Chromatographic conditions are given in text. Chromatograms from absorbance monitoring at 430, 486 and 350 nm, respectively, are shown, all at identical attenuation. Peak identification 1, 3, 5, 8, 26 and 29 = unidentified peaks 4 = valen-ciaxanthin 6 = neochrome 7 = trollichrome 9 = antherxanthin 11 = c/s-anthexanthin 12 = neoxanthin 19 = auoxanthin B 20 = c/s-violaxanthin 22 = leutoxanthin 23 = mutatoxan-thin A 24 = mutatoxanthin B 25 = lutein 27 = zeaxanthin 28 = isolutein 31 = a-cryptoxanthin 33 = /J-cryptoxanthin 34 = phytofluene 35 = a-carotene 36 = ae-carotene 37 = / -carotene. Reprinted with permission from R. Rouseff et al. [41].

During fruit ripening, the pepper carotenoid biosynthetic pathway is able to make a variety of carotenoids including [ -carotene, violaxanthin, capsombin, and capsanthin (Fig. 8.2) [18]. The latter two are ketoxanthophylls specific to peppers and are not found in other plants. Capsanthin and capsombin accumulate in red-colored peppers, while P-carotene is responsible for orange-colored fruit (Fig. 8.1). 

Fig. 3 Normal-phase HPLC separation of Valencia orange peel carotenoids. Peaks 2 — a-cryptoxanthin esters 5 = lutein diesters 6 and 7 = violaxanthin diesters 8 = luteoxanthin diesters 15 and 16 = violaxanthin monoesters 17 = luteoxanthin monoesters. The other peaks are not identified. (From Ref. 46.)...

The bright orange and yellow colors of citrus peel are due to the lipid soluble carotenoids. The more common ones in peel and juice are shown in Figure 1. Some of the first studies on citrus carotenoids were by the European workers, Zechmeister and Tuzson, in 1931 (26, 2 7, 28). They isolated p-carotene, cryptoxanthin, lutein, zeaxanthin, p-citraurin, and probably violaxanthin. In 1952, Natarajan and MacKinney (29) found phytofluene and a, p, and zeta carotenes. These studies were followed by those of Curl, who between 1953 and 1967 reported the presence of some 74 carotenoids in several citrus cultivars. 

Studies using HPLC (37 40, 41) would suggest there are fewer carotenoids in citrus than have been reported- The single most important one in the peel of oranges and tangerines is (3-citraurin, a reddish-orange carotenoid. Others include (3-cryptoxanthin, zeaxanthin, lutein, antheraxanthin, violaxanthin and to a lesser extent (3- carotene and -apo-8 -carotenal. The carotenes do not contribute very much to the color of the peel per se. 

High Phytochemical Content carotenoids (alpha- and beta-carotene, beta-cryptoxanthin, lutein, violaxanthin) polyphenols (hesperidin, anthocyanins—cyanidin and xanthone glycosides, quercetin, gallic acid, gallotannins, rhamnetin, proanthocyanidins, resveratrol) Color Code orange-yellow, purple, red-tan, green... 

Lee and Coates (2003) studied changes in carotenoid pigments as a result of thermal pasteurization of Valencia orange juices. Total carotenoid pigment content loss was signiflcant after thermal pasteurization at 90 °C for 30 s. Thermal effects on carotenoid pigment contents, especially violaxanthin (—46.4%) and antheraxanthin (—24.8%), were clearly observed. With the loss of violaxanthin and antheraxanthin, lutein became the major carotenoid, followed by zeaxanthin, in pasteurized Valencia orange juice. 

The natural occurrence of the 15-cw-isomer of violaxanthin [5,6,5, 6 -diepoxy-5,6,5, 6 -tetrahydro-/3,j8-carotene-3,3 -diol (13)] as a minor (0.6% of total carotenoid) constituent of Viola tricolor has been reported. Isomerization to fra 5-violaxanthin and c.d. correlation established the (35,5i ,6S,3 5,5 / ,6 S)-chirality. Reinvestigation of the carotenoids of Elodea canadensis failed to reveal any eloxanthin . It is proposed that the name be abandoned. A minor carotenoid from Valencia orange peel has been identified as jS-citraurin epoxide [3-hydroxy-5,6-epoxy-5,6-dihydro-8 -apo-j8-caroten-8 -al (14)]. 

Melendez-Martmez, A.J., Vicario, I.M., and Heredia, F.J. 2007. Geometrical isomers of violaxanthin in orange juice. Food Chem., 104 169-175. 

Second, their hypophasic fraction carotenoids from orange extract (PM3) and apple extract (PM4) contained mainly violaxanthin (8), zeaxanthin (9) and lutein (6). 

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