Phytoene phytofluene

Powls, R. and Britton, G., The roles of isomers of phytoene, phytofluene and zeta-carotene in carotenoid biosynthesis by a mutant strain of Scenedesmus obliquus. Arch. Microbiol. 115, 175, 1977. 

Lutein, zeinoxanthin, P-cryptoxanthin, cis-P-cryptoxanthin, a-carotene, P-carotene, phytoene + phytofluene, 9-cis P-carotene, 13-cw P-carotene... 

Tomato skin SC-CO2 0.5 0.05-0.25 n.i. phytoene, phytofluene, -carotene, (3-carotene, lycopene... 

Sample Lutein Lycopene Neuro Phytoene Phytofluene Lycopene-... 

N.A. Crocine glycosides, beta-carotene, phytoene, phytofluene, pinene, safranal, cineole.100-107 Saffron stomachic, antispasmodic, emmenagogue properties. 

Lycopene is the major carotenoid pigment found in tomatoes, along with lesser amounts of a-, P-, y-, and -carotene, phytoene, phytofluene, neurosporene, and lutein (Trombly and Porter, 1953 Kargl et al., 1960). The basic physicochemical information on lycopene is fairly well established and is outlined in Table 4.1. Lycopene is dispersible in edible oils and soluble in apolar organic solvents. In aqueous systems, lycopene tends to aggregate and to precipitate as crystals this behavior is suspected to inhibit the bioavailability of lycopene in humans (Zumbrunn et al., 1985). In fresh tomatoes, the crystalline form of lycopene is responsible for the typical bright red of the ripe fruits. 

The degree of unsaturation in the molecule, i.e. the length of the conjugated polyene chromophore, has a substantial effect on retention times. Thus the acyclic hydrocarbons of the biosynthetic desaturation series, namely phytoene, phytofluene, tetrahydrolycopene, neurosporene and lycopene are well resolved, as are compounds having the same substituent group but different levels of desaturation, e.g. the 1-hydroxy-derivatives of these hydrocarbons. The 1,2-dihydrocarotenes, found in Rps. viridis are eluted later than their parent hydrocarbons e.g. 1,2-dihydroneurosporene after neurosporene. 

Phytofluene. Porter and Lincoln s work with various tomato selections indicated the presence of phytofluene, along with other precursors (7). In an enzyme system obtained by ammonium sulfate precipitation of proteins from spinach (Spinacia oleracea) leaves, phytoene, phytofluene, and lycopene were produced from labeled isopentenyl pyrophosphate (11). Curiously, no f-carotene or neurosporene was reported. 

Fruits with relatively high contents of lycopene, phytoene, phytofluene, -carotene and neurosporene, e. g., peaches. 

The desaturation of l5-cis phytoene into lycopene occurs in four stepwise dehydrogenations, yielding phytofluene, ( -carotene, neurosporene and lycopene... 

P = phytoene PF = phytofluene -C = -carotene L = lycopene y-C = y-carotene p-C = p-carotene Lut = lutein Viola = violaxanthin Neo = neoxanthin d.p.b. days post breaker. 

Fig. 2.16. HPLC profile of carotenoids in an extract of vegetable soup. An expansion of the profile from 30 to 39 is shown in the inset (A). Monitored wavelengths were 436, 440, 464, and 409 nm for peaks 9,10,11,12, and 14, respectively, in the inset (A). Peak identification 1 + 1" = all-trans-lutein and cw-lutein 2 = 5,6-dihydroxy-5,6-dihydrolycopene (lycopene-5,6-diol) 3 = j3-apo-8 -carotenal (internal standard) 4 = lycopene 1,2-epoxide 5 = lycopene 5,6-epoxide 6 = 1,2-dimethoxyproly-copene (tentative identification) 7 = 5,6-dimethoxy-5,6-dihydrolycopene 8 = lycopene 9 = pheo-phytin b 10 = neurosporene 11 = (-carotene 12 = pheophytin a 13 = (-carotene 14 = pheophytin a isomer and (-carotene 15 = a-carotene 16 and 16" = all-trans-/fcarotene, cis-/J-carotene 17 and 17" = all-trans- or cA-phytofluene 18 and 18" = all-trans- or cw-phytoene. Reprinted with permisson from L. H. Tonucci et al. [40].

Kinetic studies of the incorporation of the " C-labelled precursors mevalonic acid, isopentenyl pyrophosphate, and phytoene into C40 carotenes by Halobac-terium cutirubrum cell-free preparations" produced results consistent with the pathways outlined in Schemes 2 and 3. Only the trans-isomers seemed to be involved. A mutant strain, " PGl, of the green alga Scenedesmus obliquus accumulates phytoene (135), phytofluene (136), and -carotene (137) in place of the... 

Scheme 7.5 Formation of some aroma compounds after oxidative cleavage of a acyclic carotenoids (e.g., lycopene, phytofluene and phytoene) and b cyclic carotenoids (e.g. a-carotene and / -caro-tene)...

In the APPI method of ionization, the solvent is vaporized in a heated nebulizer and the gaseous analytes are then ionized with photons from a lamp (Rivera et ah, 2011). It has been observed that certain solvents, called dopants, enhance the ionization of analytes via this technique. To date only one study has been published with carotenoids and APPI (Rivera et ah, 2011). APPI was compared to ESI and APCI as ionization techniques, and the authors observed that APPI positive produced approximately a 2- to 4-fold greater total ion signal for lycopene and (3-carotene as compared to APCI positive and ESI positive. In contrast, APCI positive outperformed APPI positive for a number of xantho-phylls and phytoene and phytofluene. 

No carotenoids were detected in tissues of animals sacrificed after 6 weeks. However, as shown in Table 10.4, after 24 weeks, nearly all carotenoids (lutein, zeaxanthin, lycopene, y-carotene, -carotene, a-carotene, P-carotene, phytofluene, phytoene) were bioavailable in colon and liver of the animals that received MCM. A typical HPLC profile of carotenoids in a pooled extract from mouse liver is shown in Figure 10.2. The major carotenoids in brain were lycopene, lutein, and P-carotene. Carotene predominated in the breast tissues, while lutein, lycopene, y-carotene, and a-carotene were detected in low concentrations. Carotenoids were not detected in tissues of the mice on WD without MCM. 

Even people who have been taking blood pressure-lowering drugs will benefit from this natural choice. And individuals who are determined to get their blood pressure down without drugs will benefit enormously. Tomato extract, which is rich in the antioxidant polyphenols lycopene, phytoene, and phytofluene, has been shown to reduce blood pressure for treated but not completely controlled hypertensive individuals, as well as for never-treated men and women in the category of prehypertension. Two studies have been done at the University of the Negev in Beer Sheva, Israel, by Dr. Esther Paran and her colleagues. 

The metabolism and pharmacokinetics of the carotenoids are not well understood, and their bioavailabUity is associated with much interindividual and intraindividual variation (281). p-Carotene, a-carotene, cryptoxanthin, lycopene, and lutein are the major carotenoids in human serum, and lycopene and p-carotene are the major carotenoids in other human tissues (282). Small amounts of zeax-anthin, phytofluene, and phytoene are also found in various organs. Various carotenoids tend to be present in similar ratios in human plasma and tissues (282, 283). The carotenoids are safe and even long-term intake of 180 mg of p-carotene per day did not lead to hypervitaminosis. When large amounts of carotenoids are stored in the adipose and other lipid-rich tissues, they may cause reversible yellowing of the... 

Interest in the action of various chemicals on carotenoid biosynthesis has been maintained in Phycomyces blakesleeanus and its mutants, diphenylamine caused increased levels of phytoene and phytofluene and reduced levels of coloured carotenes, whereas dimethyl sulphoxide reduced both types.The drug AMO 1618 increased the levels of all types of carotenoids in all strains, probably by preventing cyclization of GGPP and so increasing the amount of this precursor available for dimerization. The Et2NCH2 group in the amines (106)—(108) was... 

In the photosynthetic bacteria Rhodomicrobium vannielii, which normally contains acyclic carotenoids with tertiary hydroxy- and methoxy-groups at C-1 and C-T, phytoene only accumulated when diphenylamine was present, but the occurrence of hydroxy-derivatives of phytofluene, 7,8,11,12-tetrahydrolycopene, neurosporene, and lycopene in the presence of the inhibitor indicated that hydroxylation could take place at any level of desaturation although only the more desaturated half of the molecule was so substituted. 

Sandman et. l. (8) have found the N-phenyl-2-phenoxynicotin-amides to be powerful inhibitors of phytoene desaturase. Several bleaching herbicides that inhibit the phytoene to phytofluene transformation have the same 3-trifluoromethylphenyl group (8, 9). This group includes norflurazon, metflurazon, fluridone, 7luometuron and fluorochloridone. In the nicotinamide series the same 3-trifluoromethylphenyl group gives optimum herbicide activity. 

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