Synthesis Of Β-carotene Research Articles

The influence of phytochrome on the formation of individual carotenoids in etiolated hordeum seedlings

Short time red pulses, given 6 times for 5 min within 36 h, induce in etiolated barley seedlings an enhanced synthesis of the main chloroplast carotenoids beta-carotene, violaxanthine, lutein and neoxanthine. The level of antheraxanthine and zeaxanthine decreases by red light treatment. These red light effects are reverted by subsequent short time far-red pulses. The results show that the white light induced change in the accumulation rate of individual carotenoids is initiated and regulated by active phytochrome Pfr. In the case of neoxanthin and zeaxanthin the red light effects cannot be fully reverted by far-red; this points to a very fast phytochrome reaction.

Biogenesis of beta-carotene in Mycobacterium kansasii.

The biogenesis of beta-carotene in the photochromogen Mycobacterium kansasii consists of two reactions. The first reaction is photochemical, and is dependent on the wavelength of the incident light and on oxygen but is independent of temperature. The second reaction does not require illumination, and is dependent on the temperature and on oxygen. The latter, or dark reaction, requires the synthesis of new protein, and was shown to have the characteristics of an inducible system. Carotenogenesis was stimulated by incident light of wavelengths of 420, 540, and 650 nm. Immediately after illumination there was an increase in the synthesis of ribonucleic acid and beta-carotene accumulation started after a lag of 8 to 10 min. The synthesis of beta-carotene exhibited temperature dependence with an optimum of about 36 C.

Tissue differentiation and plumbagin synthesis in variant cell strains of plumbago zeylanica L. in vitro

Chemical analysis of 3 different cell strains derived from stem explants of Plumbago zeylanica and cultured in vitro varied in pigmentation and morphology. The plumbagin content was highest in the anthocyanin-pigmented strain. The induction of roots in the nodular strain did not influence plumbagin synthesis. Chlorophyll induction in a non-pigmented strain was accompanied by the synthesis of β-carotene and trace amounts of plumbagin. The plumbagin content of variant cell strains in culture has been compared to that of isolated parts of the intact plant.

Die Synthese von Lipochinonen und isoprenoiden Pigmenten bei der Ergrünung von Etioplasten im Blaulicht / Synthesis of Lipoquinones and Isoprenoid Pigments during Greening of Etioplasts in Blue Light

Abstract Blue light induces in etioplasts of Hordeum seedlings parallel to the formation of chlorophyll an increased synthesis of carotenoids, plastidic benzoquinones and vitamin K1. 1. Blue light induces an enhanced synthesis of β-carotene, lutein, violaxanthin, and neoxanthin, while the levels of antheraxanthin and zeaxanthin are decreased. 2. In contrast to the etiolated tissue a much higher portion of total plastoquinone-9 (oxidized and reduced form) is formed in blue light than total α-tocopherol (+ α-tocoquinone), and a higher portion of the oxidized quinone forms plastoquinone-9 and α-tocoquinone. 3. The blue-light-induced changes of the isoprenoid lipid synthesis described here are similar to those obtained in continuous far-red light. It is, therefore, suggested that blue light is effective via the blue absorption bands of the phytochrome system. 4. Blue-light-induced greening of etioplasts results in a much higher synthesis rate of chlorophyll a and other isoprenoid thylakoid lipids as compared to red light. This enhancement of thylakoid lipid formation appears to be a special blue light effect.

Investigations in the area of the synthesis ofβ-carotene

Investigations in the area of the synthesis ofβ-carotene

Transcription and translation for carotenoid synthesis in Chlamydomonas reinhardtii

The sites of transcription and translation of carotenoid pigments were studied in synchronously grown cells of Chlamydomonas reinhardtii Dang. Rifampicin, cycloheximide and spectinomycin were used to distinguish between the nuclear-cytoplasmic genetic system and the genetic system of the chloroplast. Since rifampicin is without effect, chloroplast DNA appears not to possess information required for the synthesis of carotenoids. Carotenoid synthesis parallels chlorophyll synthesis in these cells. Carotenoid synthesis is dependent on de novo protein synthesis both on cytoplasmic and chloroplast ribosomes, for both cycloheximide and spectinomycin are effective inhibitors. However, the cells are able to form about 40% of the expected increase in carotenoids when cytoplasmic and chloroplast ribosomes are simultaneously inhibited. Of the major carotenoids in C. reinhardtii, lutein appears the least dependent on de novo protein synthesis. The synthesis of β-carotene and trollein appears to be completely dependent on the function of cytoplasmic ribosomes.

Separation of β-Factor Synthesis from Stimulated β-Carotene Synthesis in Mated Cultures ofBlakeslea trispora

Mated cultures of Blakeslea trispora, grown in a potato extract-glucose-thiamine medium, produced 10 to 15 times more beta-carotene than either unmated culture. Mated, but not unmated, cultures produced a family of compounds (beta factor) which stimulated carotenogenesis in unmated cultures. In fact, carotenogenesis was stimulated sixfold more in minus cultures than in plus cultures. By altering the relative amounts of plus and minus inocula used in fermentations of mated cultures, it was possible to separate the synthesis of beta factor from the synthesis of extra beta-carotene. The plus strain appeared to produce the beta factor; the minus strain appeared to produce most of the extra beta-carotene. Kinetic studies of beta-factor formation suggested that physical contact between the two strains may be required to initiate beta-factor synthesis.

Temperature Inhibition of Carotene Synthesis in Tomato

1. Seven different pigment strains of tomato were studied. In each type a number of excised fruits were matured at either 23.5⚬C. or 32.0⚬C. and the quantities of phytoene, phytofluene, α-carotene, β-carotene, ζ-carotene, ψ-carotene, prolycopene, δ-carotene, γ-carotene, neurosporene, and lycopene were determined. 2. With the exception of β-carotene and possibly prolycopene, production of all of the pigments and polyenes measured was reduced at 32⚬C. Some pigments appeared to be more sensitive to the higher temperature than others. Lycopene synthesis was drastically inhibited at 32⚬C. in every strain which produced this pigment. 3. Beta-carotene synthesis was not inhibited at 32⚬C. in the standard red tomato. When the pigments of this type were enhanced by the introduction of the high pigment factor (hp), the enlarged β-carotene fraction was not temperature sensitive. In the Tangerine type, where very little β-carotene is produced, no inhibition of its synthesis could be demonstrated. In these strains, β-carotene could hardly be synthesized from lycopene as has been postulated. 4. In strains which have enhanced β-carotene fractions resulting from the presence of either the gene B or the delta factor (Del), the increased synthesis of β-carotene was inhibited by maturation at 32⚬C. The evidence suggests that this β-carotene is synthesized by a different pathway than that of the standard red tomato.

Microbiological production of carotenoids. VII. Influence of hydrocarbon on carotenogenesis by mated cultures of Blakeslea trispora.

Synthesis of beta-carotene by mated strains of Blakeslea trispora in shaken-flask culture was considerably enhanced by adding either 5% kerosene after 2 days of fermentation or acid-refined kerosene at the start of fermentation to a grain-based medium that also contained a natural lipid, nonionic detergent, and beta-ionone; average yields of 17,500 mug per g of dry fermentation solids (86,000 mug per 100 ml of medium) were attained when refined kerosene was used. Almost all of the carotene was retained within the mycelium. Peak yields were achieved in 5 days.

Synthesis of β-Carotene in the Tomato Fruit

1. Two tomato crosses were examined. By use of the pigment mutant apricot (at at) which inhibits the production of lycopene in the fruit of the tomato but does not inhibit the "normal" production of β-carotene, it was shown that the action of the gene B in producing more than normal quantities of β-carotene is dependent upon a system which would otherwise produce lycopene in quantity. Support for this view is derived from a cross in which the quantity of lycopene was enhanced genetically, resulting in an appropriate increase in β-carotene in B-carrying strains. 2. These results support earlier investigations with regard to the action of B and enhance an earlier suggestion that, in the fruit of the tomato, β-carotene may be derived by two separate paths.

Synthesen in der Carotinoid‐Reihe. 5. Mitteilung. Anwendungen der Reaktion von Whiting

AbstractStarting from various C40‐diols, 7, 7′‐dihydro‐β‐carotene, dehydro‐ retro‐carotene (isocarotene) and three new carotenoids were synthesized by the reaction of Whiting. In addition a new synthesis of β‐carotene from β‐C18‐ketone, acetylene and vitamin A‐aldehyde is described.

Studies in carotenogenesis. 7. Further observations concerning the action of diphenylamine in inhibiting the synthesis of beta-carotene in Phycomyces blakesleeanus.

Studies in carotenogenesis. 7. Further observations concerning the action of diphenylamine in inhibiting the synthesis of beta-carotene in Phycomyces blakesleeanus.

SYNTHESIS OF β-CAROTENE

SYNTHESIS OF β-CAROTENE