Cis-violaxanthin

Snyder, A.M., Clark, B.M., Robert, B., Ruban, A.V., and Bungard, R.A. 2004. Carotenoid specificity of light-harvesting complex II binding sites Occurrence of 9-cis violaxanthin in the neoxanthin-binding site in the parasitic angiosperm cuscuta reflexa. J. Biol. Chem. 279 5162-5168. 

An enzyme system from the yeast Saccharomyces cerevisiae is able to incorporate isoprenoid precursors into the C30 phytoene analogue (200) only in the presence of Mn and absence of NADPH. If NAD PH is present and Mn is replaced by Mg, the sterol precursor squalene (201) is produced.The substrate specificity of the chloroplast enzyme violaxanthin deepoxidase has been examined.In addition to the normal substrate violaxanthin [(35,5/ ,65,3 5,5 i ,6 5)- 5,6,5, 6 -diepoxy-5,6,5, 6 -tetrahydro-/3,j8-carotene-3,3-diol, (196)] several all-trans-monoepoxy-carotenoids, such as anthera-xanthin [5,6-epoxy-5,6-dihydro-/3,/3-carotene-3,3 -diol (197)], diadinoxanthin [5,6-epoxy-7, 8 -didehydro-5,6-dihydro-j8, 8-carotene-3,3 -diol (198)], and /3-cryptoxanthin epoxide [5,6-epoxy-5,6-dihydro-/3,/3-caroten-3-ol (199)], all with the 38,5R,6S) configuration, were utilized. Violeoxanthin (9-cis-violaxanthin) and other 9-cis-isomers were not affected. A carrot Daucus carota) tissue culture has been shown to incorporate [ C]acetate into carotenoids. ... 

First, among these results, the content of lutein (all trans-lutein, 6)in total xanthophylls was most abundant, followed by violaxanthin (8), 9"-cis-violaxanthin (64) and 9 -c/s-neoxanthin (67, lutein-5,6-epoxide (lutein epoxide, 61), and others. Interestingly, on their percentage on the enzymatic conversion of lutein (all trans-lutein, 6)to lutein-5,6-epoxide (lutein epoxide, 61), Abbot 9.3% was more efficient, followed by Monty, Heyward and Bruno, respectively. 

P-cryptoxanthin, -carotene, 5,6-epoxylutein, transviolaxanthin, cis-violaxanthin, and neoxanthin (Lashbrooke etal. 2010). 

There are basically two types of carotenoids those that contain one or more oxygen atoms are known as xanthophylls those that contain hydrocarbons are known as carotenes. Common oxygen substituents are the hydroxy (as in p-cryptoxanthin), keto (as in canthaxanthin), epoxy (as in violaxanthin), and aldehyde (as in p-citraurin) groups. Both types of carotenoids may be acyclic (no ring, e.g., lycopene), monocyclic (one ring, e.g., y-carotene), or dicyclic (two rings, e.g., a- and p-carotene). In nature, carotenoids exist primarily in the more stable all-trans (or all-E) forms, but small amounts of cis (or Z) isomers do occur. - ... 

Carotene (all-trans), (3-cryptoxanthin (all-trans and -cis), zeaxanthin (all-trans), luteoxanthin isomers, violaxanthin (all-trans and -cis), and neoxanthin (all-trans and -cis) were identified in several mango cultivars (Mercadante and others 1997 Ornelas-Paz and others 2007, 2008). Mango retinol was found to be highly bioavail-able by estimating vitamin A and carotene reserves in the liver and plasma of rats. Information on the tocopherol content in mango is very scarce, but it seems to be low (Burns and others 2003 Ornelas-Paz and others 2007). 

Fig. 2.26. Reversed-phase HPLC separation of (a) Sobrasada sausage extract and (b) saponified Sobrasade sausage extact in an ODS column at maximum absorbances at each point in time. Peak identification 1 - 2, 4 - 6, 8, 12, 14-17 = unidentified free 3 = capsorubin 7 = violaxanthin 9 = capsanthin 10 = anteraxanthin 11 = cw-capsanthin 13 = lutein and zeaxanthin 18 = cantaxanthin, internal standard 19 = cryptoxanthin 20, 24, 25, 28 = unidentified monoester 21 = /J-cryptoxanthin 22 = capsorubin monoester 23, 26, 27, 29 = capsanthin monoester 30, 31 = lutein-zeaxanthin monoester 32 = /1-carotene 33 = cis-f)-carotene 34, 37, 39, 41, 43 = capsanthin diester 35 = capsorubin diester 36, 38, 40, 42, 44 = unidentified diester. Reprinted with permission from J. Oliver et al. [56],...

The complete separation from I-carotene to violaxanthin requires 35 min. Figure F2.3.4 illustrates the separation of carotenoids in a mixed food extract using this LC system. The hydrocarbon carotenes ( -carotene, a-carotene, lycopene) elute together at the solvent front. The elution order is fi-cryptoxanthin, u-cryptoxanthin, lutein, cis-lutein, zeaxanthin, cis-zeaxanthin, neoxanthin, and violaxanthin. 

Some common carotenoids found in nature are all-frans-P-carotene, lycopene, a-car-otene, P-cryptoxanthin, canthaxanthin, zeaxanthin, antheraxanthin, violaxanthin, lutein, 9-cis-P-carotene, and 15,15- s-phytoene. 

Gruszecki WI, Matula M, Ko-chi N, Koyama Y and Krupa Z (1997) Cis-trans isomerization of violaxanthin in LHCII violaxanthin isomerization within the violaxanthin cycle. Biochim Biophys Acta 1319 267-274 Hashimoto H and Koyama Y (1988) Time-resolved Raman spectroscopy of triplet y3-carotene produced from all-trans, 7-is, 13-cis and 15-cis isomers and high-pressure liquid chromatography analyses ofphotoisomerisation via the triplet state. J Phys Chem 92 2101-2108 Hashimoto H and Koyama Y (1989a) Raman spectra of all-trans /3-carotene in the SI and T1 states produced by direct photoexcitation. Chem Phys Lett 163 251-256 Hashimoto H and Koyama Y (1989b) The C=C stretching Raman lines of/3-carotene isomers in the S state as detected by pump-probe resonance Raman spectroscopy. Chem Phys Lett 154 321-325... 

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