Showing papers on "Neoxanthin published in 1984"
TL;DR: From spectroscopic and chemical evidence prasinoxanthin is assigned the structure 3,6,3′ trihydroxy-7,8-dihydro-γ,e-caroten-8-one, with tentative 3R,6R chirality from biogenetic considerations, thus representing the first algal carotenoid with a γ-end group.
70 citations
TL;DR: The carotenoids in two members of the Raphidophyceae (chloromonads) Gonyostomum semen and Vacuolaria virescens and of two tentative members of this class Chattonella japonica were analyzed quantitatively and identified by methods including mass spectrometry and chemical derivatizations.
Abstract: 1. 1. The carotenoids in two members of the Raphidophyceae (chloromonads) Gonyostomum semen and Vacuolaria virescens , and of two tentative members of this class Chattonella japonica and Fibrocapsa japonica were analyzed quantitatively and identified by methods including mass spectrometry and chemical derivatizations. 2. 2. Group I ( G. semen and V. virescens ) showed a similar carotenoid pattern, comprised of diadinoxanthin (54–60% of total carotenoid), dinoxanthin (8–17%), β,β-carotene (7%) and heteroxanthin (7%), as well as neoxanthin (G. semen , 3%), an epoxidic monoacetate ( G. semen , 12%), an epoxidic carotenol = 9′- cis -diadinoxanthin? ( V. virescens , 8%), an epoxidic diacetate ( V. virescens , 2%) and vaucheriaxanthin 3,19-diacetate ( V. virescens , 8%). Both chlorophyll c forms ( c 1 and c 2 ) were detected in V. virescens ; ratio a / c 1 + c 2 , 20:1. This pigment composition resembles that of the Xanthophyceae. 3. 3. Group II ( Chattonella japonica and Fibrocapsa japonica ) exhibited a different carotenoid pattern with fucoxanthin (40–68%), fucoxanthinol (3–42%), β,β-carotene (15–27%) and violaxanthin (1–2%) in common. C. japonica also contained zeaxanthin (1%). This carotenoid pattern resembles that of Chrysophyceae. 4. 4. Characteristic features common to the carotenoids encountered are a high proportion of epoxidic carotenoids (78–86%), allenic carotenoids (24–82%), acetylated carotenols (18–81%) and acetylenic carotenoids (61–67%; Group I only). 5. 5. A scheme for the carotenoid biosynthesis that could lead to both observed patterns is proposed. The present analyses require a revision of phylogenetic schemes based on the photosynthetic pigments.
27 citations
TL;DR: From the pigment data it is concluded that the C(4), C(3) and CAM species seem to possess during drought a higher proportion of pigment-proteins of PSI than pigment- Protein of PS II, which is related to the differences in the pigment composition of the species.
16 citations
TL;DR: Evidence is presented suggesting that the chloroplast envelope does not contain carotenoids and quinones in vivo, contrary to previous findings.
Abstract: Leaves, cotyledons, isolated chloroplasts and subplastid fractions (thylakoids and envelopes) of radish (Raphanus sativus L. cv. Saxa) and spinach (Spinacia oleracea L. cv. Matador) were assayed for their pigment and quinone content and composition. Evidence is presented suggesting that the chloroplast envelope does not contain carotenoids and quinones in vivo. Envelopes prepared by the method described contained very low amounts of chlorophyll a and b, violaxanthin and neoxanthin, but no β-carotene, lutein, zeaxanthin and antheraxanthin. Among the quinones, trace amounts of plastoquinone and α-tocopherol but no plastohydroquinone, α-tocoquinone and phylloquinone were detected. The data presented suggest that, contrary to previous findings, carotenoids and quinones are not located in the chloroplast envelope.
9 citations
TL;DR: The pigments of seven local Cucurbita varieties were determined in this paper, and only carotenoids with alfa-and beta-iononic structure were identified.
Abstract: The pigments of seven local Cucurbita varieties were determined In the fruits only carotenoids with alfa- and beta-iononic structure were identified: hydrocarbon carotenoids (alfa- and beta-carotene), xanthophylls (cryptoxanthin, aloxanthin, mutatoxanthin, auroxanthin, violaxanthin, neoxanthin) Quantitatively, the main carotenoid pigments are beta-caroten and zeaxanthin, flavoxanthin and violaxanthin There are differences among the varieties of C maxima, both quantitatively and qualitatively, due to genetic and/or environmental influences
3 citations
TL;DR: Carotenoids, chlorophyll, tobacco (flue-cured), flue curing, senescence, pigment concentrations progressively declined during plant growth; this degradation was accelerated during flue cured.
Abstract: Neoxanthin, violaxanthin, lutein, β-carotene, chlorophyll a and chlorophyll b in the leaves of flue-cured tobacco (Nicotiana tabacum L.) were determined in samples collected at intervals from the middle of July through harvest. Harvested leaves were also sampled at intervals during flue curing for pigment determinations. Except where interrupted by rainfall or irrigation, pigment concentrations progressively declined during plant growth; this degradation was accelerated during flue curing. Carotenoid degradation during flue curing was proportional to the degree of oxygen substitution of the carotenoid. Chlorophyll a and chlorophyll b in cured tissue were typically less than 1% of the amounts present at harvest.Key words: Carotenoids, chlorophyll, tobacco (flue-cured), flue curing, senescence
3 citations
01 Jan 1984
TL;DR: Britton et al. as discussed by the authors showed that the later stages of carotenoid biosynthesis take place in the chloroplast, and several biosynthetic transformations have been achieved with isolated chloroplasts.
Abstract: Chloroplasts from almost all higher plant leaves contain the same collection of main carotenoids, i.e. β-carotene (frequently accompanied by some α-carotene) and the xanthophylls lutein, violaxanthin and neoxanthin, usually with smaller amounts of zeaxanthin, antheraxanthin and lutein 5,6-epoxide. These carotenoids are constituents of pigment-protein complexes which are located in highly specific orientations in photosynthetic reaction centres and light-harvesting assemblies in the thylakoid membranes. It has also been reported that, in some plant species, some carotenoid, particularly violaxanthin, may be present in the chloroplast envelope (Jeffrey et al., 1974). The carotenoids are biosynthesized within the chloroplast, and several biosynthetic transformations have been achieved with isolated chloroplasts (see Britton, 1982, for a review of carotenoid biosynthesis in higher plants). The relative contributions of cytoplasm and chloroplast to the synthesis of mevalonate for terpenoid biosynthesis are not clear, but there can be little doubt that the later stages of carotenoid biosynthesis take place in the chloroplast. The actual site or sites of synthesis within the plastid remains unknown.
1 citations
TL;DR: Green lamina, when severely injured, showed significant changes in certain chemical and physical parameters studied, which were reflected by significant decreases in the chlorophylls, β-carotene, lutein, neoxanthin, and violaxanthin.
Abstract: A late-season frost in southwestern Ontario resulted in a loss of a third of the projected 1982 flue-cured tobacco, Nicotiana tabacum L., production. Green leaf tissue was collected representing three levels of freezing injury as well as no visible injury and these four treatments were cured. Certain chemical and physical characteristics were measured on these treatments to relate visible freezing injury to quality losses. Green lamina, when severely injured, showed significant changes in certain chemical and physical parameters studied. These were reflected by significant decreases in the chlorophylls, β-carotene, lutein, neoxanthin, and violaxanthin. In cured lamina, the contents of reducing sugars, fructose, glucose, sucrose, inositol, Fe, and malic, palmitic, stearic, oleic, linoleic, linolenic, neochlorogenic, chlorogenic, and 4-0-caffeoylquinic acids decreased with the increase of freezing injury. Starch, citric acid, scopoletin, and lamina weight increased markedly in severely damaged lamina. Lamin...
1 citations