番茄红素

1.Lycopene(番茄红素,502-65-8) is a naturally occuring red carotenoid pigment that is responsible in red to pink colors seen in tomatoes, pink grapefruit, and other foods. Having a chemical formula of C40H56, lycopene is a tetraterpene assembled from eight isoprene units that are solely composed of carbon and hydrogen. Lycophene may undergo extensive isomerization that allows 1056 theoretical cis-trans configurations; however the all-trans configuration of lycopene is the most predominant isomer found in foods that gives the red hue. Lycopene is a non-essential human nutrient that is classified as a non-provitamin A carotenoid pigment since it lacks a terminal beta ionone ring and does not mediate vitamin A activity. However lycophene is a potent antioxidant molecule that scavenges reactive oxygen species (ROS) singlet oxygen. Tomato lycopene extract is used as a color additive in food products.

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2.Lycopene(番茄红素,502-65-8) is a linear, unsaturated hydrocarbon carotenoid, the major red pigment in fruits such as tomatoes, pink grapefruit, apricots, red oranges, watermelon, rosehips, and guava. As a class, carotenoids are pigment compounds found in photosynthetic organisms (plants, algae, and some types of fungus), and are chemically characterized by a large polyene chain containing 35-40 carbon atoms; some carotenoid polyene chains are terminated by two 6-carbon rings. In animals, carotenoids such as lycopene may possess antioxidant properties which may retard aging and many degenerative diseases. As an essential nutrient, lycopene is required in the animal diet.

1.Functional Validation of a Phytoene Synthase and Lycopene ε-Cyclase Genes for High Lycopene Content in Autumn Olive Fruit (Elaeagnus umbellata)/PMID 32936623; Journal of agricultural and food chemistry 2020 Sep; :/Name matches: beta-carotene lycopene
Abstract：Lycopene is the most potent antioxidant amongst all carotenoids and is beneficial for human health. The ripe fruit of autumn olive (Elaeagnus umbellata Thunb.) accumulate a high level of lycopene, which is 5- to 20-times higher than that of ordinary tomato. During the fruit ripening of autumn olive, only phytoene synthase (EutPSY) expression pattern shows a tight positive correlation with the increased lycopene content observed at four ripening stages, while the lycopene ε-cyclase (EutLCYe) transcript could not be detected throughout fruit ripening. Here, we investigated whether the two genes are important targets for engineering lycopene biosynthesis. The full-length cDNAs of EutPSY and EutLCYe were firstly isolated. Fruit-specific overexpression of EutPSY in tomato fruits resulted in elevated contents of lycopene and β-carotene through feed-forward regulation of carotenogenic genes, i.e. down-regulation of SlLCYe and up-regulation of SlLCYb and SlCYCB. These fruit were decreased in ethylene production throughout ripening. Transcript levels of genes for system-2 ethylene synthesis (SlACS2, SlACS4, SlACO1 and SlACO3), perception (SlNR/ETR3 and SlETR4), and response (SlE4 and SlE8) were also inhibited in EutPSY-overexpressing fruit. Repressing ethylene synthesis and signaling transduction delayed fruit climacteric ripening of transgenic tomato plants. Additionally, RNAi suppression of SlLCYe enhanced β-carotene but not lycopene accumulation through altered expression of carotenogenic genes in transgenic tomato fruit by both feed-forward and feed-back regulatory mechanisms. Ethylene production in SlLCYe -RNAi fruit decreased, thereby delaying fruit ripening. Collectively, these results confirmed that transcriptional regulation of EutPSY and EutLCYe play a crucial role and a part in the massive lycopene accumulation in autumn olive fruit, respectively. EutPSY overexpression enhanced lycopene accumulation in tomato fruit independently of ethylene pathway, but did not influence the size and weight of tomato fruit. EutPSY can be used as an effective strategy capable of elevating lycopene content in fruit for improving quality.

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2.Comparison of the bioavailability and intestinal absorption sites of phytoene, phytofluene, lycopene and β-carotene/PMID 31352286; Food chemistry 2019 Dec; 300(?):125232/Name matches: beta-carotene lycopene
Abstract：The mechanisms of main tomato carotenes (phytoene, phytofluene, lycopene and β-carotene) intestinal absorption are still only partly understood. We thus compared carotene bioavailability in mice after gavage with carotene-rich oil-in-water emulsions. We also determined each carotene absorption profile along the duodenal-ileal axis of the intestine to identify their respective absorption sites and compared these profiles with the gene expression sites of their identified transporters, i.e. SR-BI and CD36. Our data show that phytofluene presented a significantly higher bioavailability compared to lycopene and β-carotene (areas under the curve of 0.76 ± 0.09 vs. 0.30 ± 0.05, 0.09 ± 0.05 and 0.08 ± 0.01 μmol/L·h for phytofluene, phytoene, lycopene and β-carotene, respectively). β-Carotene was mostly converted in the proximal and median intestine. Phytoene and phytofluene accumulation tended to be more important in the distal intestine, which did not correlate with the proximal expression of both Scarb1 and CD36. Overall, these results highlight the high bioavailability of phytofluene.

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3.The bifunctional identification of both lycopene β- and ε-cyclases from the lutein-rich Dunaliella bardawil/PMID 31615667; Enzyme and microbial technology 2019 Dec; 131(?):109426/Name matches: beta-carotene lycopene
Abstract：The halophilic green alga Dunaliella bardawil FACHB-847 is rich in lutein and α-carotene, which has great potential for carotenoid production in open ponds. In this study, genes encoding lycopene β- and ε-cyclases (DbLcyB and DbLcyE) from D. bardawil FACHB-847 were functionally identified by genetic complementation in E. coli. The bifunctional DbLcyB not only catalyzed the formation of both mono- and bi-cyclic β-rings with a major β-cyclase activity, but also possessed a weak ε-cyclase activity. In contrast, DbLcyE preferred to convert lycopene into monocyclic δ-carotene, and possessed a weak β-monocyclase activity. Lutein and α-carotene were the prominent carotenoids in D. bardawil FACHB-847, which was in agreement with the result of genetic complementation of co-expression of DbLcyB and DbLcyE in E. coli with α-carotene as the prominent product. The bifunctional DbLcyB and DbLcyE may contribute to the high accumulation of α-carotene in D. bardawil FACHB-847. Interestingly, the accumulation of lutein in D. bardawil FACHB-847 was more sensitive to salt stress, while the accumulation of β-carotene in D. salina CCAP 19/18 was induced by salt stress. In brief, the production of different carotenoid compositions from these two Dunaliella species can be induced by different growth conditions.