Presence of carotenoids in Gordius aquaticus (Nematomorpha,Nemathelminthes) specimens from deep wells

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.     

β-Carotene producing mutants of Phaffia rhodozyma

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.     

The mass culture of Dunaliella viridis (Volvocales,Chlorophyta) for oxygenated carotenoids : laboratory and pilot plant studies

The biology, and hence the mass culture, of Dunaliella viridis closely follows that of Dunaliella salina, which is successfully mass cultured for the production of -carotene. Both algae can grow at extremely high salinities and light intensities. They co-exist in the coastal salt lake, Hutt Lagoon, Western Australia. In contrast to D. salina, D. viridis does not accumulate large amounts of -carotene, producing only up to 0.7% of mixed carotenoids (lutein, zeaxathin, other oxygenated carotenoids and -carotene), compared to D. salina's ca 10% dry wt of mainly -carotene. However, in laboratory experiments, D. viridisgrew much faster and to much higher cell densities than D. salina, and attained levels of mixed carotenoids similar to those of D. salina (ca 13 mg L^–1 carotenoid). Preliminary experiments in outdoor ponds were much less promising. Harvesting by chemical flocculation was as effective as with D. salina, but extraction of carotenoids directly into vegetable oil proved inefficient. When incorporated into feed, caretonoids derived from D. viridis pigmented hen eggs acceptably. Extrapolating from laboratory results, and using costing derived from D. salina technology, the cost of production of mixed oxygenated carotenoids from D. viridis was similar to that for the production of -carotene from D. salina, at ca $A500 kg^–1.     

Characterization of carotene accumulation inUstilago violacea using high-performance liquid chromatography

Quantitative analysis of carotene accumulation in white, pink, pumpkin, orange, and yellow haploid strains ofUstilago violacea by high-performance liquid chromatography indicated that specific patterns of carotene accumulation are primarily responsible for the white, pumpkin, orange, and yellow phenotypes. The yellow strains accumulated primarily -zeacarotene and -carotene. The white strains accumulated primarily the colorless carotene, phytoene, or did not accumulate any carotene at all. Carotene accumulation in pink haploid strains followed the same patterns as for the white, pumpkin, orange, or yellow strains. Pink diploid and disomic strains ofU. violacea with various parental combinations of the color mutations accumulated either cis--zeacarotene and -carotene or only -carotene. The pattern of carotene accumulation in conjunction with the available genetic information for the carotene loci inU. violacea was used as a basis for the construction of a new genetic model for carotene biosynthesis inU. violacea. The model employs three dehydrogenases and one cyclase for the synthesis of -carotene from phytoene, and accounts for the carotene accumulation patterns of either cis--zeacarotene and -carotene or lycopene, -carotene, and -carotene.     

The neutral carotenoids of wild-type and mutant strains of Neurospora crassa

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.     

Interactions of photosynthetic pigments in monolayers at a water-air interface

Summary The compression of mixtures of photosynthetic pigments and phosphatidylcholine in monolayers at a water-air interface shows that (i) the phosphatidylcholine disperses the isolated pigment molecules; (ii) chlorophyllsa andb, chlorophylla and -carotene, and chlorophyllb and -carotene form associations which cannot be undone by the phospholipids; and (iii) when the two chlorophylls and -carotene are mixed all together with or without phosphatidylcholine, the three types of associations are ideally mixed and they can be dispersed by phosphatidylcholine.     

Production of deuterated β-carotene by metabolic labelling of Spirulina platensis

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.     

American Cockroach (Periplaneta americana) Synthesizes Carotenoids from the Precursor [14C]Mevalonic Acid Pyrophosphate

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.     

Carotenogenesis and asparagine inLeptosphaeria michotii (West) Sacc.

Summary InLeptosphaeria michotii U¹⁴C-asparagine was incorporated into the coloured carotenoids, the synthesis of which carried on till day 8. The pigment turnover, obvious from day 6, was not modified by the light conditions used.Nicotine (0.25 to 4.5 mM) has been used to study carotenogenesis and sporulation rhythm regulation inL. michotii fed with asparagine 2.6 mM. Control cultures contained in darkness -carotene only and in continuous light -carotene 98% and lycopene 2%. The mold receiving nicotine 0.25 mM in darkness contained -carotene 98% and lycopene 2%. For nicotine 0.5 mM and upwards -carotene decreased, lycopene increased and -carotene appeared, the balance between these pigments also depending on the light conditions. Whereas period length () of the sporulation rhythm increased from one cycle to the next in control cultures in darkness, it was stabilized either by continuous light ( 27 h) or by nicotine 0.25 mM ( 30 h). For nicotine 0.5 mM sporulation was uniform in darkness or in light.     

Carotenoids and Fatty Acids in Red Yeasts Sporobolomyces roseus and Rhodotorula glutinis

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).     

Cell differentiation and pigment composition in Anabaena cylindrica

Summary Cell differentiation in Anabaena cylindrica is accompanied with characteristic changes in the pigment composition of heterocysts and spores. In both the absence of phycocyanin is consistent with the lack of CO₂-fixing ability previously reported. The presence of chlorophyll and -carotene suggests a functional photosystem I in heterocysts. In the spores chlorophyll is largely replaced by pheophytin. The quantitative distribution of carotenoids is also affected. An increase in the proportion of -carotene is characteristic of heterocysts while spores show a larger proportion of xanthophylls compared with the intact filament.     

Carotenoids in some ultraviolet mutants of Epicoccum nigrum link

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.     

Multiple forms of P700-chlorophyll a-protein complexes from Synechococcus sp.: The iron,quinone and carotenoid contents

The iron, quinone and carotenoid contents of five P700-chlorophyll a-protein complexes having different subunit structures (CP1-a,-b,-c,-d and-e) from the thermophilic cyanobacterium Synechococcus sp. were determined. CP1-a,-b,-c and-d that commonly have four polypeptides of 62,000, 60,000, 14,000 and 10,000 dalton contained 10–14 iron atoms per P700, whereas CP1-e that lacks the two small polypeptides was totally devoid of iron. All CP1 complexes contained vitamin K₁ at the molar ratio of vitamin K₁ to P700 of about 2 except CP1-e that had only 0.4 vitamin K₁ per P700. No plastoquinone was detected in five CP1 complexes. Out of four major carotenoids, -carotene, zeaxanthin, caloxanthin, and myxoxanthophyll, present in the thylakoid membranes, only -carotene was found in isolated CP1 complexes; all CP1 complexes contained about 10 -carotene molecules per P700. The flourescence excitation spectrum showed that -carotene serves as an efficient antenna of photosystem I. It is concluded that all iron atoms and a larger fraction of vitamin K₁ molecules present in the photosystem I reaction center complex are associated with the 14,000 and 10,000 dalton polypeptides, whereas -carotene exclusively binds to the large polypeptides which carry the functional and antenna chlorophyll a. The possible functions of iron and vitamin K₁ as electron carriers and of -carotene as the accessary pigment and a photoprotectant in the photosystem I complexes are discussed.     

Investigations of carotenoids in some faunal elements of the Adriatic Sea. IV-molluscs

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     

Carotenoids of Rhizobia

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     

Carotenoids in fish. XXIV. Sardina pilchardus Walb. (Clupeidae)

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).     

Carotenoids in Ostrea edulis L. (Bivalvia: Ostreacea) from the lagoon of Venice (Italy)

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.     

Qualitative and quantitative composition of pigments in Phaeodactylum tricornutum (Bacillariophyceae) stressed by iron

The effect of Fe(III) deficiency on qualitative and quantitative changes in pigment composition in Phaeodactylum tricornutum Bohlin was demonstrated by HPLC and AAS. Maximum content of pigments showed the diatom cells incubated at the optimum iron concentration, i.e., 10 M. The contents of chlorophyll a, chlorophyll c ₁+c ₂, fucoxanthin, diadinoxanthin and ,-carotene were 109.99, 20.16, 40.39, 1.29 and 1.48 fg per cell, respectively. The results obtained showed that Fe(III) affected qualitative and quantitative pigment composition in P. tricornutum. The content of individual pigments, proportions between accompanying pigments and their ratios to chlorophyll a were important indicators of phytoplankton response to iron stress. The strong reduction in ,-carotene content, several times (2–5) increase in diadinoxanthin level as compared to ,-carotene, and high amount of diadinoxanthin in relation to chlorophyll a were observed in algae growing at very low Fe(III) concentrations, 0.001 and 0.01 M. The data suggested that phytoplankton pigments could be a potential physiological marker.     

Carotenoids in the muscles of Orconectes limosus (Raf. ) (Crustacea- Decapoda)

Summary The presence of carotenoids pigments in the muscles of Orconectes limosus (Raf.) (Decapoda, Crustacea)- was studied.In extracts separated by means of column and thin-layer chromatography, the following carotenoids were indentified : -carotene, cantaxanthin, lutein, zeaxanthin, neoxanthin, ketocarotenoid and astaxanthin.     

Carotenoid composition in milo (Sorghum vulgare) shoots as affected by phytochrome and chlorophyll

The composition of coloured carotenoids in the milo shoot was investigated quantitatively (high performance liquid chromatography) during light-mediated plastidogenesis, including the time span of photodelay as caused by medium and high light fluxes. It was found that as long as only the far-red-absorbing form of phytochrome operates, the carotenoid pattern remains virtually the same as in complete darkness (violaxanthin and lutein as major constituents, traces of -carotene). On the other hand, the pattern changes dramatically in white or red light with increasing amounts of chlorophyll (lutein and -carotene dominate, -carotene showing the strongest relative increase). Photodelay during the early phase of plastidogenesis affects the carotenoid composition strongly. Increase of neoxanthin, violaxanthin and -carotene contents are diminished while lutein accumulation proves resistant towards chlorophyll-mediated photoinhibition. The photodelay can be diminished by an appropriate light pretreatment. The data indicate that light-mediated control over carotenoid accumulation is exerted at three levels: i) a coarse control through phytochrome, ii) fine tuning in connection with chlorophyll accumulation, iii) stabilization of holocomplexes against photodecomposition.Abbreviations GG14 high fluence rate green-yellow light - HPLC high-performance liquid chromatography - Chl chlorophyll - WL_w weak white light (1200 lx) - WL_m medium flux white light (12000 lx)