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Photooxidative processes play a role in the pathobiochemistry of various disorders of light-exposed tissue. After irradiation of skin with UV light, erythema (sunburn) is an initial effect suitable for monitoring the direct biological response. Carotenoids are efficient in photoprotection, scavenging singlet oxygen and peroxyl radicals. Intervention studies with supplements or a carotenoid-rich diet documented efficiency in systemic photoprotection, measuring a decreased sensitivity against UV-induced erythema. For successful intervention, treatment with carotenoids is needed for a period of at least ten weeks. An increased consumption of carotenoids may contribute to life-long protection against UV-induced damage.  相似文献   

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Consumption of carotenoids is associated with an enhanced immune response and protection against neoplasia and atherosclerosis. Because these effects have been achieved using carotenoids with no pro-vitamin A activity, they are assumed to be due to the antioxidant properties of carotenoids. Carotenoids protect against photosensitized oxidation by quenching singlet oxygen. In addition, beta-carotene reacts chemically with peroxyl radicals to produce epoxide and apocarotenal products. To investigate the potential significance of these reactions to biological systems, we have used soybean lipoxygenase to generate peroxyl radical enzymatically. beta-Carotene inhibits the oxidation of linoleic acid by soybean lipoxygenase as well as the formation of the hydroperoxide product. In addition, the absorption of beta-carotene is diminished (bleached) by soybean lipoxygenase. The potential significance of these antioxidant reactions of carotenoids to biological function is discussed.  相似文献   

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The author investigated the presence of various carotenoids in the eggs of Oncorhynchus keta by means of columnar and thin-layer chromatography. The investigations revealed the presence of the following carotenoids: canthaxanthin, lutein-epoxide, 4-hydroxy-4-keto-ß-carotene, tunaxanthin, astaxanthin ester and asterin acid. Astaxanthin ester comprised the greatest part, 67.8% of, all carotenoids.  相似文献   

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B. Czeczuga 《Hydrobiologia》1979,64(3):251-259
The author investigated the presence of various carotenoids in Salmo gairdneri Rich. and Salmo trutta morpha fario L. from the trout fish farm (artificial food) and from the river as the natural conditions (natural food).The findings of these investigations indicate that the trout bred in natural conditions are richer in carotenoids, provitamins of vitamin A, than are trout from the trout fish farm. In all probability the variety of food available in natural conditions provides better facilities for the accumulation of carotenoids in the body of trout in their natural habitat.  相似文献   

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B. Czeczuga 《Hydrobiologia》1980,70(3):197-199
The author investigated the presence of various carotenoids in three species of the Syngnathidae family by means of columnar and thin-layer chromatography. The investigations revealed the presence of the following carotenoids: canthaxanthin, lutein, lutein epoxide, zeaxanthin, astaxanthin (free and ester form) and 4-hydroxy-4-keto--carotene. Ketocarotenoids (astaxanthin and canthaxanthin) comprised the greatest part  相似文献   

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Summary The isolation, morphology and growth chracteristics of pure cultures of a Thiothece, Lamprocystis and Thiodictyon strain are described.Their carotenoid composition is reported. The Thiothece strain produced in addition to okenone (1), several related ketocarotenoids, among which a demethylated okenone (6) was identified by a small scale total synthesis. Thiodictyon and Lamprocystis produced carotenoids of the rhodopinal (previously warmingone) series, the latter organism contained as major carotenoids a lycopenol (4), not previously found in Nature, and a cross-conjugated lycopenal (2), previously called anhydro-warmingone.Part 7. Acta chem. scand. 21, 2185 (1967).  相似文献   

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The carotenoids of selected Cryptophyceae, Rhodomonas D3 and Cryptomonas ovata, have been examined by methods including HPLC, mass spectrometry 1H NMR and circular dichroism. 3′R,6′R-Chirality has been assigned to monadoxanthin from 1H NMR and CD data; β,?-carotene possessed the common 6′R-chirality. The quantitative distribution pattern of carotenoids in Cryptophyceae established here and previously, totalling five species' is discussed in chemosystematic context. β,?-Carotene (3–8% of total) is the major carotene, accompanied by ?,?-carotene (0.2%), β,β-carotene (0–1%) and lycopene (0-trace). Zeaxanthin (2%) was identified in C. ovate. The diacetylenic alloxanthin is the major carotenoid (70–88%), and the monoacetylenic crocoxanthin (5–15%) and monadoxanthin (0–16%) less abundant. No epoxidic or allenic carotenoids could be detected. The biosynthetic precursor of acetylenic carotenoids in this primitive algal class is discussed. The significance of Cryptophyceae in the marine food chain is commented on, using alloxanthin as an indicator.  相似文献   

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With increasing concentrations in the growth medium of the cyclization inhibitors nicotine or 2-(4-chlorophenylthio)-triethylamine hydrochloride (CPTA) the previously identified bicyclic carotenoids of Rhizobium lupini (2,3,2,3-tetrahydroxy-,-caroten-4-one and 2,3,2,3-tetrahydroxy-,-carotene) were successively replaced by hitherto unknown monocyclic carotenoids. By application of mass and nuclear magnetic resonance spectroscopy 3 carotenoids were identified as 2,3-trans-dihydroxy-,-caroten-4-one, 2,3-trans-dihydroxy-,-carotene, and 3-hydroxy-,-caroten-4-one. A further compound was tentatively established as (2- or 3-)monohydroxy-,-carotene. It was found that other inhibitors such as diphenylamine or 4-chloro-5-(dimethylamino)-2-,,(trifluoro-m-tolyl)-3-(2H)-pyridazinone (San 6706) did not affect the pigment pattern. The results are discussed in relation to carotenoid biosynthesis in Rhizobium lupini.Abbreviations CPTA 2-(4-chlorophenylthio)-triethylamine hydrochloride - San 6706 4-chloro-5-(dimethylamino)-2-,,-(trifluoro-m-tolyl)-3-(2H)-pyridazinone  相似文献   

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The presence of 14 leaf carotenoids was studied in 26 species of gymnosperms. Rhodoxanthin was present in all the species of the Taxaceae, Taxodiaceae and Cupressaceae.  相似文献   

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Summary The carotenoid composition of 25 pure isolates of Thiorhodaceae has been studied. The 17 carotenoids encountered can, on the basis of chemical and biochemical considerations, be grouped into the spirilloxanthin, okenone and warmingone series. Most of the isolates examined synthesize carotenoids belonging to one of these groups only—the so-called normal spirilloxanthin series being the most common.The distribution pattern of carotenoids in phototrophic bacteria in general is briefly discussed, and the implications of the carotenoid composition in the taxonomy of the sulphur purple bacteria are evaluated.
Zusammenfassung Die Carotinoid-Zusammensetzung von 25 Thiorhodaceae-Stämmen wurde untersucht. Aus chemischen und biochemischen Gründen können die 17 aufgefundenen Carotinoide in die Spirilloxanthin-, Okenon- und Warmingon-Reihen zusammengefaßt werden. Die meisten der untersuchten Stämme bilden Carotinoide, die nur zu einer dieser Gruppen gehören, von denen die sogenannte normale Spirilloxanthin-Reihe am häufigsten vorkommt. Das Verteilungsmuster der Carotinoide bei phototrophen Bakterien wird kurz dargestellt und der Wert der Carotinoid-Zusammensetzung für die Taxonomie der Schwefel-Purpurbakterien diskutiert.


No. III of this series Arch. Mikrobiol. 46, 138 (1963).  相似文献   

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Biosynthesis of Carotenoids in Brevibacterium sp. KY-4313   总被引:2,自引:0,他引:2       下载免费PDF全文
The biosynthesis of 4-keto and 4,4′-diketo carotenoids in Brevibacterium sp. KY-4313 was studied. Echinenone and canthaxanthin were isolated from the cultures grown on a medium containing several n-alkanes. When glutathione was added to the bacterial cultures, the formation of canthaxanthin was inhibited while β-carotene and its hydroxy derivatives accumulated. It is suggested that these 4-hydroxy compounds, isocryptoxanthin, isozeaxanthin, and 4-hydroxy-4′-keto-β-carotene, are intermediates in the biosynthesis of canthaxanthin. In the presence of 2-(4-chlorophenylthio)-triethylamine hydrochloride or nicotine, lycopene and neurosporene accumulated. The β-carotene level decreased slightly but β-zeacarotene remained unchanged. β-carotene and its derivatives were resynthesized upon removal of the inhibitors. It was concluded that cyclization can take place at either the neurosporene or lycopene level in Brevibacterium sp. KY-4313.  相似文献   

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B Czeczuga 《Folia biologica》1991,39(1-4):17-20
The presence of carotenoids in Catopus tritis infernus Szymanowski 1957 and Choleva lederiana gracilenta Szymanowski 1957 from a cave was studies, using columnar and thin-layer chromatography. Qualitative and quantitative differences in the carotenoid content of these insect species were found.  相似文献   

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Three varieties of crab apples and two varieties of eating appleshave been investigated for their carotenoid contents. ß-caroteneis not always the major carotenoid and epoxy-carotenoids arefound in fairly large amounts. There are relatively more carotenesthan xanthophylls in two of the crab apples while the reverseis observed in the eating apples studied. Cox's Orange Pippincontains 33 I.U. of vitamin A activity, Golden Delicious 3.6,while the crab apple Golden Hornet has 132 I.U. per gramme dryweight. Further, the peel has a greater concentration of carotenoidsthan the flesh except in the crab apple Pyrus baccata wherethe ratio is 1: 1  相似文献   

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