- Preparation of 9 Z-β-Carotene and 9 Z-β-Carotene High-Loaded Nanostructured Lipid Carriers: Characterization and Storage Stability
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Cis (Z)-β-carotenes with 25.3% 9Z-β-carotene were prepared for nanostructured lipid carriers (NLCs). The optimal conditions for NLC preparation using an orthogonal experimental method were as follows: the total lipid concentration was 9% (w/v), the surfac
- Yang, Cheng,Yan, Hongxiao,Jiang, Xin,Xu, Huaneng,Tsao, Rong,Zhang, Lianfu
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- Insight into β-carotene thermal degradation in oils with multiresponse modeling
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The aim of this study was to gain further insight into β-carotene thermal degradation in oils. Multiresponse modeling was applied to experimental highperformance liquid chromatography-diode array detection (HPLC-DAD) data (trans-, 13-cis-, and 9-cis-β-car
- Achir, Nawel,Penicaud, Caroline,Avallone, Sylvie,Bohuon, Philippe
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- A synthesis method of 9-cis Beta-carotene
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The present invention relates to a method for synthesizing 9 - cis Beta-carotene (9 - cis beta-carotene) compounds having high purity and easy mass production through a chemical reaction, and a reaction for substituting 9 - cis Retinol groups of Alcohol with 9 - cis Phosphonium salt. The reaction of β - (3 - Methyl-2-butenal to Knoevenagel condensation) to synthesize All-trans Aldehyde. In step 9 - cis Retinoic Phosphonium salt) and in step), the completed All-trans Aldehyde is subjected to Wittig Olefination reaction with carbon double bonds, and 9. cis Beta-carotene obtained by the reaction of carbon double bonds.
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- Bidirectional Hiyama–Denmark Cross-Coupling Reactions of Bissilyldeca-1,3,5,7,9-pentaenes for the Synthesis of Symmetrical and Non-Symmetrical Carotenoids
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The construction of the carotenoid skeleton by Pd-catalyzed Csp2?Csp2 cross-coupling reactions of symmetrical and non-symmetrical 1,10-bissilyldeca-1,3,5,7,9-pentaenes and the corresponding complementary alkenyl iodides has been developed. Reaction conditions for these bidirectional and orthogonal Hiyama–Denmark cross-coupling reactions of bisfunctionalized pentaenes are mild and the carotenoid products preserve the stereochemical information of the corresponding oligoene partners. The carotenoids synthesized in this manner include β,β-carotene and (3R,3′R)-zeaxanthin (symmetrical) as well as 9-cis-β,β-carotene, 7,8-dihydro-β,β-carotene and β-cryptoxanthin (non-symmetrical).
- Rivas, Aurea,Pérez-Revenga, Víctor,Alvarez, Rosana,de Lera, Angel R.
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p. 14399 - 14407
(2019/11/03)
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- METHOD FOR SYNTHESIS OF 9-CIS-BETA-CAROTENE AND FORMULATIONS THEREOF
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The present invention relates to a method for total chemical synthesis of 9-cis-β-carotene (9CBC), and further provides stable formulations thereof.
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- Biochemical characterization and selective inhibition of β-carotene cis-trans isomerase D27 and carotenoid cleavage dioxygenase CCD8 on the strigolactone biosynthetic pathway
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The first three enzymatic steps of the strigolactone biosynthetic pathway catalysed by β-carotene cis-trans isomerase Dwarf27 (D27) from Oryza sativa and carotenoid cleavage dioxygenases CCD7 and CCD8 from Arabidopsis thaliana have been reconstituted in vitro, and kinetic assays have been developed for each enzyme, in order to develop selective enzyme inhibitors. Recombinant OsD27 shows a UV-visible λmax at 422 nm and is inactivated by silver(I) acetate, consistent with the presence of an iron-sulfur cluster that is used in catalysis. OsD27 and AtCCD7 are not inhibited by hydroxamic acids that cause shoot branching in planta, but OsD27 is partially inhibited by terpene-like hydroxamic acids. The reaction catalysed by AtCCD8 is shown to be a two-step kinetic mechanism using pre-steady-state kinetic analysis. Kinetic evidence is presented for acid-base catalysis in the CCD8 catalytic cycle and the existence of an essential cysteine residue in the CCD8 active site. AtCCD8 is inhibited in a time-dependent fashion by hydroxamic acids D2, D4, D5 and D6 (> 95% inhibition at 100 μm) that cause a shoot branching phenotype in A. thaliana, and selective inhibition of CCD8 is observed using hydroxamic acids D13H and D15 (82%, 71% inhibition at 10 μm). The enzyme inhibition data imply that the biochemical basis of the shoot branching phenotype is due to inhibition of CCD8.
- Harrison, Peter J.,Newgas, Sophie A.,Descombes, Flora,Shepherd, Sarah A.,Thompson, Andrew J.,Bugg, Timothy D. H.
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p. 3986 - 4000
(2015/10/28)
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- Novel strigolactone analogues and their use
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Novel compounds of formula I their use as germination trap for parasitic weeds, for the regulation of branching, tillering and root development, for enhancement of cambium growth, for the regulation of hyphal growth of mycorrhizal fungi and compositions c
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Page/Page column 10
(2012/11/13)
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- Semiconductor photocatalysis: Photodegradation and trans-cis photoisomerization of carotenoids
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In the presence of semiconductor CdS or ZnO particles, irradiation (>350 nm) of all-trans-β-carotene (II) in dichloromethane leads to rapid degradation of the carotenoid, which is relatively stable in the absence of the semiconductors. Canthaxanthin (I), however, undergoes significant photocatalyzed degradation only on ZnO, not on CdS. High-performance liquid chromatographic studies indicate that CdS catalyzes trans-cis photoisomerization of both I and II. As in the photoisomerization in the absence of semiconductor, the major cis isomers have the 9-cis and 13-cis configuration, but, under otherwise the same condition, the ratio of cis/trans isomers has doubled. In contrast to CdS, ZnO does not catalyze the photoisomerization of either I or II, although it enhances their rate of degradation. A photoisomerization mechanism involving carotenoid radicals formed by reaction with interstitial sulfur on the CdS surface is proposed.
- Gao, Guoqiang,Deng, Yi,Kispert, Lowell D.
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p. 3897 - 3901
(2007/10/03)
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- Oxidative degradation kinetics of lycopene, lutein, and 9-cis and all-trans β-carotene
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The thermal and oxidative degradation of carotenoids was studied in an oil model system to determine their relative stabilities and the major β-carotene isomers formed during the reaction. All-trans β-carotene, 9-cis β-carotene, lycopene, and lutein were heated in safflower seed oil at 75, 85, and 95 °C for 24, 12, and 5 h, respectively. The major isomers formed during heating of β-carotene were 13-cis, 9-cis, and an unidentified cis isomer. The degradation kinetics for the carotenoids followed a first-order kinetic model. The rates of degradation were as follows: lycopeneall-trans β-carotene≈9-cis β-carotenelutein. The values for the thermodynamic parameters indicate that a kinetic compensation effect exists between all of the carotenoids. These data suggest that lycopene was most susceptible to degradation and lutein had the greatest stability in the model system of the carotenoids tested. Furthermore, there was no significant difference in the rates of degradation for 9-cis and all-trans β-carotene under the experiment conditions.
- Henry,Catignani,Schwartz
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p. 823 - 829
(2007/10/03)
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- Kinetic Model for Studying the Isomerization of α- and β-Carotene during Heating and Illumination
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The thermoisomerization and iodine-catalyzed photoisomerization of all-trans-α- and all-trans-β-carotene were kinetically studied using regression models. Carotene samples were heated at varied temperatures or exposed to a 20 W light for varied lengths of time. Isomerization and degradation reactions were monitored using HPLC with diode array detection. Four cis isomers of β-carotene and three cis isomers of α-carotene were separated and detected. The degradations of both carotenes under heating at 150 deg C or iodine/light treatment may fit the reversible first- order model. 9-cis and 13-cis were the major β-carotene isomers formed during heating, while 13,15-di-cis was favored during iodine-catalyzed photoisomerization. The formation of 9-cis and 13-cis form all-trans-α-carotene was dependent upon the extent of heat or iodine/light treatment, and the latter was formed in greater amount under either treatment. Keywords: α-Carotene; β-carotene; thermoisomerization; photoisomerization; kinetic study
- Chen, B. H.,Chen, T. M.,Chien, J. T.
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p. 2391 - 2397
(2007/10/02)
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- Triplet-Sensitized and Thermal Isomerization of All-Trans, 7-Cis, 9-cis, 13-Cis, and 15-Cis Isomers of β-Carotene: Configurational dependence of the Quantum Yield of Isomerization via the T1 State
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The products of triplet-sensitized photoisomerization (excitation at 337 nm of the sensitizer, anthracene) and thermal isomerization of β-carotene in n-hexane, starting from the all-trans, 7-cis, 9-cis, 13-cis, and 15-cis isomers, were analyzed by HPLC.Direct photoisomerization (excitation at 488 and 337 nm) was also examined for comparison.Three different isomerization patterns were found in both triplet-sensitized and thermal isomerization: pattern A, cis to trans isomerization around each cis bond; pattern B, trans to cis isomerization in the central part of the conjugated chain; and pattern C, cis to another cis isomerization.In the T1 state, the pattern A isomerization was predominant even for the peripheral-cis (7-cis and 9-cis) isomers and its efficiency was extremly high for the central-cis (13-cis and 15-cis) isomers.In the S0 state, the pattern B isomerization, instead, was predominant for the peripheral-cis isomers, and the pattern A isomerization was predominant only for the central-cis isomers.The quantum yields of triplet-sensitized isomerization (decrease of the starting isomer per triplet species generated) were determined to be as follows: all-trans, 0.04; 7-cis, 0.12; 9-cis, 0.15; 13-cis, 0.87; and 15-cis, 0.98.In direct photoisomerization, the quantum yield of isomerization at 488-nnm (337 nm) excitation was 4 (3) orders of magnitude lower than the above values, the relative values among the isomers being similar to the above.Further, the overall isomerization patterns of direct photoexcitation were similar to those of triplet-sensitized isomerization, supporting the idea that isomerization takes place via the T1 state even in the case of direct photoexcitation.Carbon-carbon ? bond orders of model polyenes in the T1 and S0 states were calculated by using the Pariser-Parr-Pople CI theorie; bond lengths were optimized by using a bond order-bond length relationship.Isomerization characteristics in the T1 and S0 states observed were discussed based on the results of the calculations.
- Kuki, Michitaka,Koyama, Yasushi,Nagae, Hiroyoshi
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p. 7171 - 7180
(2007/10/02)
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