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1.
B. Czeczuga 《Hydrobiologia》1981,76(1-2):13-15
By means of columnar and thin-layer chromatography, the presence of carotenoids in Gordius aquaticus L. (Nematomorpha, Nemathelminthes) from deep wells was studied.The investigations revealed the presence of the following carotenoids: -carotene, mutatochrome, -cryptoxanthin, ,-carotene epoxide,lutein, zeaxanthin and astaxanthin ester.  相似文献   

2.
The neutral carotenoids of wild-type Neurospora crassa and of carotenoid mutants at four discrete genetic loci were isolated using gradient elution chromatography on deactivated alumina columns. Carotenoids were identified by absorption spectrophotometry and thin layer cochromatography with carotenoid standards. Phytoene, phytofluene, -carotene, -carotene, neurosporene, torulene, lycopene, and 3,4-dehydrolycopene were isolated from wild type. Phytoene, phytofluene, -carotene, -carotene, neurosporene, -carotene, lycopene, and one unknown carotenoid, tentatively identified as 15,15-cis--carotene, were isolated from a yellow mutant, ylo-1. ylo-1 also contained residual carotenoids having similar absorption spectra to, but very different chromatographic behavior from, phytofluene, -carotene, -carotene, and lycopene. Albino and colored al-1 mutants contained large amounts of phytoene and only traces of other neutral carotenoids. Albino al-2 and al-3 mutants contained only traces of neutral carotenoids.  相似文献   

3.
The carotenoids in the molluscsClanculus cruciatus, Patella coerulea, Mytilus galloprovincialis, Sepia officinalis andLoligo vulgaris from the Adriatic sea were investigated. Their presence was determined by means of columnar and thin-layer chromatography. The following carotenoids were found inC. cruciatus; mytiloxanthin-like, lutein, lutein ester, zeaxanthin and astaxanthin-like; inP. coerulea: mytiloxanthin-like, lutein, lutein ester, lutein-5,6-epoxide, zeaxanthin and astaxanthin-like; inM. galloprovincialis: -carotene, mytiloxanthin-like, lutein, lutein ester, lutein-5,6-epoxide and zeaxanthin; inS. officinalis: -carotene, lutein, lutein ester, tunaxanthin and zeaxanthin; inL. vulgaris: -carotene, -carotene, -carotene, -cryptoxanthin, isocryptoxanthin, isorenieratene, capsanthin, capsorubin, mutatochrome, triophaxanthin, zeaxanthin, 4-hydroxy--carotene and 4-keto--carotene  相似文献   

4.
Summary In this first article on the carotenoids of Myxobacterales we report on the minor carotenoids of Stigmatella aurantiaca: phytoene, phytofluene, lycopene, -carotene, 4-keto--carotene, 1,2-dihydro-1-hydroxy--carotene, 4-keto-1,2-dihydro-1-hydroxy--carotene, 4-keto-1,2-dihydro-1-hydroxy-torulene, and 1,2,1,2-tetrahydro-1,1-dihydroxy-lycopene. These pigments account for about 10% of total carotenoids.  相似文献   

5.
The level of an important carotenoid (-carotene) in the gut of Periplaneta americana depends on the content of the carotenoid in food: a carotenoid-fortified diet causes accumulation of -carotene up to 10 g/g wet weight, while on a carotenoid-deficient diet the level of this substance is low (0.7 g/g wet weight). In the eye, in contrast to the gut, a constant level of -carotene (1.3-1.4 g/g wet weight) is found regardless of the diet. This phenomenon remained unchanged over three years of feeding of the cockroaches with the carotenoid-deficient diet, suggesting that P. americana produces carotenoids by de novo biosynthesis. This suggestion was confirmed in experiments using intraperitoneal injection of the exogenous carotenoid biosynthesis precursor [14C]mevalonic acid pyrophosphate followed by extraction of carotenoid and chromatographic purification of the labeled product. Injection of 3.4 nmoles [14C]mevalonic acid pyrophosphate transiently increased the -carotene content in eyes on days 2 and 4 after injection of the label. Purification of radiolabeled carotenoids from eye and gut by the transfer of carotenoids into a less polar solvent, alkaline hydrolysis (saponification), and chromatography on alumina and cellulose columns decreased the specific radioactivity to a constant level that cannot be further decreased by repeated chromatography. The elution profile of these purified preparations of -carotene after chromatography is characterized by coincidence of symmetric peaks of count and absorption. We suggest that to create the optimal carotenoid concentration in the eye, P. americana uses two biochemical mechanism: 1) it accumulates carotenoids in reserve in the gut when abundant supplies of carotenoids are available in the diet; 2) it synthesizes carotenoids de novo when its food is deficient in these compounds.  相似文献   

6.
By means of columnar and thin-layer chromatography the presence of carotenoids in Ostrea edulis L. (Bivalvia: Ostreacea) from the Lagoon Venice (Italy), was studied.The following carotenoids were founds: -, -, -carotene, -carotene epoxide, lutein (free and epoxide from), zeaxanthin, diatoxanthin, mutatoxanthin and astaxanthin. The dominating carotenoids were lutein.The total contents varied within the range of 5.4–8.1 µg/g wet weight.  相似文献   

7.
Rhodotorula glutinis and Sporobolomyces roseus, grown under different aeration regimes, showed differential responses in their carotenoid content. At higher aeration, the concentration of total carotenoids increased relative to the biomass and total fatty acids in R. glutinis, but the composition of carotenoids (torulene > -carotene > -carotene > torularhodin) remained unaltered. In contrast, S. roseus responded to enhanced aeration by a shift from the predominant -carotene to torulene and torularhodin, indicating a biosynthetic switch at the -carotene branch point of carotenoid biosynthesis. The overall levels of total carotenoids in highly aerated flasks were 0.55 mol-percent and 0.50 mol-percent relative to the total fatty acids in R. glutinis and S. roseus (respectively), and 206 and 412 g g–1 dry weight (respectively).  相似文献   

8.
Summary Mutants were produced by ultraviolet irradiation of the mould Epicoccum nigrum Link. The qualitative and quantitative formation of carotenoid pigments was studied. In addition to the four carotenoids present in the wild-type strain 5-I-3 several other carotenoids were isolated and identified.The presence of these pigments is discussed. The results support the proposed pathway for the biosynthesis of rhodoxanthin, 3,3-diketo-retro--carotene, from -carotene.  相似文献   

9.
Method for production of deuterated -carotene for the bioavailability studies of vitamin A has been developed using Spirulina platensis in culture. Suspension cultures of Spirulina in heavy water (99.4% D2O) medium produced maximum biomass and -carotene in 28 to 30 days. Of the total carotenoids, lutein constituted 30 to 35% while -carotene was about 24%. MS showed that 60 to 65% H atoms in -carotene were deuterated. 100% replacement of H atom with deuterium was achieved by preventing exchange with atmospheric moisture. The medium could be used in several cycles for metabolic labelling of carotenoids whereby the cost of production is reduced.  相似文献   

10.
B. Czeczuga 《Hydrobiologia》1980,69(3):277-279
The author investigated the presence of various carotenoids in Sardina pilchardus Walb. from the coast of Southern Europe.The presence of the following carotenoids has been stated: -carotene, -carotene epoxide, -cryptoxanthin, canthaxanthin, lutein epoxide, zeaxanthin, astaxanthin (free and ester form) and mutatochrome. The dominant carotenoid in all the parts of the body was astaxanthin, especially its ester form. The total content of carotenoid ranged from 10.537 (skin and muscles) to 116.309 µg/g fresh weight (liver).  相似文献   

11.
Summary Transfer of a UV-damaged F sex factor to a recipient lysogen induces prophage development. Under these conditions RecA protein synthesis was induced and repressor cleaved, as observed upon direct induction, that is, when the recipient lysogen was directly exposed to UV-light. The efficiency of induction of RecA protein synthesis in recipient bacteria which had received an irradiated F-lac factor was about 80% of that measured upon direct induction. We observed the simultaneous disappearance of repressor and a slight production of cleavage fragments; quantitation by densitometric scanning of the autoradiogram after correction for the efficiency of transfer indicated that 55% of repressor was cleaved. Transfer of UV-damaged Hfr DNA failed to induce RecA protein synthesis. A phage vector carrying oriF, the cloned origin of F plasmid replication, after exposure to UV-light and infection of a recipient lysogen, induced RecA protein synthesis and a moderate but significant cleavage of repressor. Indirect induction by UV-damaged F sex factor or phage oriF resulted in biochemical cellular reactions similar to those observed upon direct induction. LexA repressor that negatively controls RecA protein synthesis appeared more susceptible to cleavage than did repressor.  相似文献   

12.
Wen  Zhao  Shuang-Lin  Dong 《Hydrobiologia》2003,492(1-3):181-190
Primary productivity, biomass and chlorophyll-a of size fractionated phytoplankton (<0.22 m, <3 m, <8 m, <10 m, <40 m, <64 m, <112 m and <200 m) were estimated in 6 ponds and 5 experimental enclosures. The results showed that the planktonic algae less than 10 m are important in the biomass and production of phytoplankton in saline–alkaline ponds. The production of size fractionated phytoplankton corresponding to <112 m, <10 m and <3 m in saline–alkaline ponds were 10.5 ± 6.6 , 8.6 ± 5.4 and 0.33 ± 0.1 mgC l–1 d–1, respectively. Mean community respiration rate was 1.80 ± 0.73, 1.69 ± 0.90 and 1.38 ± 1.12 mgC l–1 d–1, respectively. The average production of phytoplankton corresponding to micro- (10–112 m), nano- (3–10 m) and pico- (<3 m) were 1.61, 8.30 and 0.33 mgC l–1 d–1, respectively. The ratio of those to the total phytoplankton production was 15%, 79% and 3%, respectively. The mean respiration rate of the different size groups was 0.11, 0.31 and 1.38 mgC l–1 d–1; the ratio of those to total respiration of phytoplankton was 6%, 17% and 77%, respectively. The production of size-fractionated phytoplankton corresponding to <200 m, <10 m and <3 m in enclosures was 2.19 ± 1.63, 2.08 ± 1.75 and 0.22 ± 0.08 mgC l–1 d-1, respectively. Mean community respiration rates were 1.25 ± 1.55, 1.17 ± 1.42 and 0.47 ± 0.32 mgC l–1 d–1, respectively. The average production of phytoplankton corresponding to micro- (10–200 m), nano- (3–10 m) and pico- (<3 m) plankton was 0.11, 1.86 and 0.22 mgC l–1 d–1, respectively. The ratio of those to the total production of phytoplankton was 5%, 85% and 10%, respectively. The mean respiration rate of different size groups were 0.08, 0.72 and 0.46 mgC l–1 d–1, the ratio of those to total respiration of phytoplankton was 6%, 57% and 37%, respectively. The concentrations of chlorophyll-a of the phytoplankton in the corresponding size of micro- (10–112 m), nano- (3–10 m) and pico- (<3 m) plankton in the experimental ponds were 19.3, 98.2 and 11. 9 g l–1, respectively. The ratio of those to the total chlorophyll-a was 15%, 76% and 9%, respectively. The concentrations of chlorophyll-a of phytoplankton micro- (10–200 m), nano- (3–10 m) and pico- (<3 m) plankton in enclosures were 1.7, 34.3 and 3.0 g l–1, respectively. The ratio of those to the total chlorophyll-a was 4%, 88% and 8%, respectively.  相似文献   

13.
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   

14.
The occurrence and contents of carotenoids in different body parts were investigated by column chromatography and TLC in Micropterus salmoides (Lalép).The following carotenoids were found: -carotene, -cryptoxanthin, -cryptoxanthin, echinenone, canthaxanthin, lutein, zeaxanthin, neothxanthin, tunaxanthin, -doradexanthin, -doradexanthin, idoxanthin, astaxanthin, astaxanthin ester, mutatochrome and mutatoxanthin.Their total contents varied within the range of 0.071–1.691 µg/g wet weight.  相似文献   

15.
Like other carotenoid-producing organisms, Phaffia rhodozyma, a red astaxanthin-producing yeast, is supposed to synthesize carotenoids by the following steps: formation of phytoene from geranylgeranyl pyrophosphate, dehydrogenation of phytoene to lycopene, cyclization of lycopene to -carotene and oxidation of the latter to astaxanthin. Mutagenic treatments generated in P. rhodozyma a wide diversity of colour variants ranging from white to dark red. The identification of the corresponding carotenoid compounds revealed the occurrence of -carotene-accumulating strains, phytoene-accumulating strains, and strains lacking any carotenoid compound. These classes of strains are likely to result from alterations in, respectively, the oxidation of -carotene, phytoene dehydrogenation and the phytoene synthetase step. Except for the cyclization of lycopene to -carotene, all the steps of carotenogenesis in P. rhodozyma are represented by the above mutants. Furthermore, astaxanthin-overproducing mutants were also selected; they are likely to be affected in some upstream step, and certainly before -carotene, as after an additional mutagenesis they generated oxidaseless strains that, in this case, overproduce -carotene. The latter strains appear very promising for biotechnological production of natural -carotene.  相似文献   

16.
Japanese parrotfish (Oplegnathus fasciatus) and Spotted parrotfish(Oplegnathus punctatus) larvae were fed with -carotene supplementedrotifers or unsupplemented control rotifers for 24 days after hatchout.Results show that survival rates of -carotene supplemented groups ofboth Japanese parrotfish and Spotted parrotfish larvae were higher than thatof control groups. -carotene supplemented and unsupplemented controlgroups exhibited similar growth in both species during this experiment.Proliferation of spleen lymphocytes with 100g ml–1 ofConA, 10 or 50g ml–1 of Poke weed mitogen from-carotene supplemented group was higher than that of a control group ofJapanese parrotfish. In Spotted parrotfish treated with 100gml–1 of ConA from the -carotene supplemented groupslymphocytes proliferated to a higher degree than in the control. Resultssuggest that the supplementation of -carotene to rotifers, might be ofbenefit in production of healthy, resistive larvae against infectiousdisease.  相似文献   

17.
Breitenbach J  Sandmann G 《Planta》2005,220(5):785-793
The plant carotenoid biosynthetic pathway to cyclic carotenes proceeds via carotene precursors in cis configuration. Involvement of individual isomers was elucidated by genetic complementation of desaturations and in vitro reactions of the corresponding enzyme. Determination of substrate and product specificity of phytoene and -carotene desaturase revealed that 15-cis-phytoene is converted to 9,15,9-tricis--carotene with 15,9-dicis-phytofluene as intermediate by the first desaturase. Prior to a subsequent conversion by -carotene desaturase, the 15-cis double bond of 9,15,9-tricis--carotene has to be (photo)isomerized to all-trans. Then, the resulting 9,9-dicis--carotene is utilized by -carotene desaturase via 7,9,9-tricis-neurosporene to 7,9,7,9-tetracis-lycopene. Other -carotene isomers that are assumed to be spontaneous isomerization products were not converted, except for the asymmetric 9-cis--carotene. This isomer is desaturated only to 7,9-dicis-neurosporene resembling a dead-end of the pathway. Prolycopene, the product of the desaturation reactions, is finally isomerized by a specific isomerase to all-trans-lycopene, which is a prerequisite for cyclization to -carotene. The 5-cis-lycopene and the 9-cis-and 13-cis--carotene isomers detected in leaves are thought to originate independently from cis precursors by non-enzymatic isomerization of their all-trans forms.  相似文献   

18.
We reported previously that the Rhodococcus erythropolis strain AN12 synthesizes the monocyclic carotenoids 4-keto -carotene and -carotene. We also identified a novel lycopene -monocyclase in this strain. Here we report the identification of the rest of the carotenoid synthesis genes in AN12. Two of these showed apparent homology to putative phytoene dehydrogenases. Analysis of Rhodococcus knockout mutants suggested that one of them ( crtI) encodes a phytoene dehydrogenase, whereas the other ( crtO) encodes a -carotene ketolase. Expression of the -carotene ketolase gene in an Escherichia coli strain which accumulates -carotene resulted in the production of canthaxanthin. In vitro assays using a crude extract of the E. coli strain expressing the crtO gene confirmed its ketolase activity. A crtO homologue (DR0093) from Deinococcus radiodurans R1 was also shown to encode a -carotene ketolase, despite its sequence homology to phytoene dehydrogenases. The Rhodococcus and Deinococcus CrtO ketolases both catalyze the symmetric addition of two keto groups to -carotene to produce canthaxanthin. Even though this activity is similar to the CrtW-type of ketolase activity, the CrtO ketolases show no significant sequence homology to CrtW-type ketolases. The presence of six conserved regions may be a signature for the CrtO-type of -carotene ketolases.Communicated by E. Cerdá-Olmedo  相似文献   

19.
A spheroplast-like slime mutant of Neurospora crassa (lacking a rigid cell wall) was found to synthesize an identical spectrum of carotenoids as wild type strains except for -carotene. Furthermore strict photoregulation of the biosynthesis of these pigments as well as the characteristics of photoinduced carotenogenesis were also nearly identical in the mutant and in the wild type.  相似文献   

20.
Dark grown Scenedesmus obliquus strain PG1 accumulated -carotene and phytoene as its major carotenoids. On illumination of dark-grown cultures in air/CO2, cyclic carotenes and xanthophylls were formed, apparently at the expense of the accumulated phytoene and -carotene. This interconversion of carotenoids was accompanied by chlorophyll synthesis. In an atmosphere of nitrogen/CO2 the light-induced changes occurred more slowly and in nitrogen alone the changes were incomplete. No massive production of cyclic carotenes from the accumulated -carotene was observed in cultures illuminated under anaerobic conditions.  相似文献   

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