THE SYNTHESIS AND CONFIGURATION OF NEO-b VITAMIN A AND NEORETINENE b

1956 ◽  
Vol 78 (11) ◽  
pp. 2651-2652 ◽  
Author(s):  
William Oroshnik
Keyword(s):  
Vitamin A ◽  
B Vitamin

scholarly journals Studi Perbandingan Komposisi Asam Lemak Daging Ikan Sidat (Anguilla marmorata (Q.) Gaimard) Fase Yellow Eel Dari Sungai Palu Dan Danau Poso

2018 ◽  
Vol 4 (1) ◽  
pp. 73-78
Author(s):  
Jamaluddin Jamaluddin ◽  
Putri Amelia ◽  
Agustinus Widodo
Keyword(s):  
Vitamin D ◽  
Vitamin E ◽  
Vitamin A ◽  
Vitamin C ◽  
Vitamin B ◽  
Yellow Eel ◽  
Anguilla Marmorata ◽  
E Protein ◽  
B Vitamin

Ikan sidat (Anguilla marmorata (Q.) Gaimard) memiliki keunggulan gizi atau nutrisi yang tinggi seperti vitamin A, vitamin B, vitamin C, vitamin D, vitamin E, protein, mineral, dan asam lemak yang baik bagi kesehatan. Penelitian ini bertujuan untuk menentukan kadar asam lemak, dan membandingkan komposisi asam lemak dari ikan sidat fase yellow eel asal sungai Palu dan danau Poso. Penelitian ini menggunakan metode kromatografi gas dengan mengubah ekstrak lemak menjadi metil ester asam lemak. Hasil analisis komposisi asam lemak daging ikan sidat (Anguilla marmorata (Q.) Gaimard) fase yellow eel asal sungai Palu dan Danau Poso menunjukan kadar asam lemak jenuh masing-masing 2,766g/100g dan 0,275g/100g; asam lemak tak jenuh tunggal 4,029g/100g dan 0,276g/100g; dan asam lemak tak jenuh ganda 0,541g/100g dan 0,102g/100g. Terdapat perbedaan secara statistik (p<0.05) komposisi dan kadar asam lemak antara daging ikan sidat fase yellow eel asal sungai Palu dan danau Poso. Komposisi asam lemak ikan sidat fase yellow eel asal sungai Palu dan danau Poso masing-masing adalah 23 dan 18 jenis. Asam lemak yang ditemukan pada daging ikan sidat sungai Palu dan tidak ditemukan pada ikan sidat danau Poso adalah asam heneikosenoat, asam miristoleat, Cis-10-pentadekanoat, asam gamma linoleat, dan Cis-11,14,17-eikosatrinoat.

scholarly journals On blood-platelets: their behaviour in “vitamin A” deficiency and after “radiation,” and their relation to bacterial infections

1922 ◽  
Vol 93 (655) ◽  
pp. 449-467 ◽  
Keyword(s):  
Vitamin A ◽  
Bacterial Infections ◽  
Vitamin A Deficiency ◽  
Blood Platelets ◽  
Water Soluble ◽  
Chronic Effect ◽  
Adult Rat ◽  
Young Rat ◽  
B Vitamin ◽  
Short Time

When the fat-soluble vitamin A is withheld from the diet of a rat, the general condition of the animal differs from that resulting from a deficiency of the water-soluble B vitamin. In the latter case the animal ceases to increase in weight almost at once, and then begins to decline. There is a progressive fall in the temperature. The animals always die within a comparatively short time-two months-and are then found to be in a state of profound emaciation, as if they had received no food at all. There is no obvious sign of disease or of an infection. For the sake of convenience, we will designate briefly this condition by the term “marasmus.” The withholding of the fat-soluble vitamin A alone affects different individual rats in a manner as varied and indefinite as the conditions obtained by a deficiency in the water-soluble B are constant and definite. When a young rat is kept on a diet from which the fat-soluble vitamin A is absent, the increase in weight may cease almost at once, or it may continue to increase in weight for many weeks, and almost as rapidly as on a diet containing vitamin A, although eventually its growth will come to a standstill before the full normal size of the adult rat has been reached. We shall, for the sake of convenience, describe these two extremes as the “acute” and the “chronic” effect on growth respectively. Eventually the rats develop infective conditions, which attack most frequently the eyes, and xerophthalmia develops. There may be other organs affected (septic glands or pneumonia sometimes develop).

scholarly journals THE VITAMIN A OF THE LOBSTER

1957 ◽  
Vol 40 (4) ◽  
pp. 609-625 ◽  
Author(s):  
George Wald ◽  
Stanley P. Burg
Keyword(s):  
Vitamin A ◽  
Equilibrium Mixture ◽  
Visual Pigments ◽  
Geometric Isomers ◽  
Free Alcohol ◽  
Fish Liver ◽  
Biological Potency ◽  
B Vitamin ◽  
Cis Isomer ◽  
Lobster Eye

In many crustacea, including the lobster, the bulk of the vitamin A of the whole animal is concentrated in the eyes. Recently Fisher, Kon, and Thompson found that vitamin A extracted from the eyes of euphausiid crustacea has only about one half the biological potency of the same amount of the all-trans acetate or fish liver vitamin A. In the present experiments the vitamin A of the lobster eye is found to consist almost entirely of the hindered cis isomer, neo-b, the precursor in the vertebrate retina of the visual pigments rhodopsin and iodopsin. This isomer is known to have a low biological potency in the rat, only about one quarter that of all-trans vitamin A. In the lobster eye it is virtually all extractable with petroleum ether, about 30 per cent in the form of free alcohol, about 70 per cent in the form of esters. It was identified by its absorption spectrum, as derived from measurements on crude extracts, and measured directly in purified preparations; the changes in absorption which accompany isomerization; oxidation to the corresponding retinene; and synthesis from the latter of rhodopsin. The examination of an extract of euphausiid eyes, provided by Dr. Kon, also revealed the presence of neo-b vitamin A virtually alone. This may be the characteristic condition in the eyes of Eucarid crustacea. It is peculiar in that the neo-b isomer, being a sterically hindered form, is ordinarily expected to be represented in any equilibrium mixture of geometric isomers in very small amount. Apparently certain crustacea have ways of circumventing the difficulties implicit in producing and retaining this isomer, and store it in the eye virtually alone.

scholarly journals RETINENE ISOMERASE

1956 ◽  
Vol 39 (6) ◽  
pp. 935-962 ◽  
Author(s):  
Ruth Hubbard
Keyword(s):  
Aqueous Solution ◽  
Vitamin A ◽  
Dark Adaptation ◽  
Pigment Epithelium ◽  
Equilibrium Mixture ◽  
Dehydrogenase System ◽  
Dominant Process ◽  
B Vitamin ◽  
Cis Isomer

Rhodopsin is formed by the condensation of opsin with a cis isomer of retinene, called neo-b. The bleaching of rhodopsin releases all-trans retinene which must be isomerized back to neo-b in order for rhodopsin to regenerate. Both retinene isomers are in equilibrium with the corresponding isomers of vitamin A, through the alcohol dehydrogenase system. An enzyme is found in cattle retinas and frog pigment layers which catalyzes the interconversion of all-trans and neo-b retinene. We call it "retinene isomerase." It is soluble in neutral phosphate buffer, and precipitates between 20 and 35 per cent saturation with ammonium sulfate. In the dark, the isomerase converts all-trans and neo-b retinene to an equilibrium mixture of 5 parts neo-b and 95 parts all-trans. With opsin present to trap neo-b, the isomerase catalyzes the synthesis of rhodopsin from all-trans retinene. This reaction, however, is too slow to account for dark adaptation. Retinene is isomerized by light, but too slowly to supply the retina with neo-b. In aqueous solution the pseudoequilibrium mixture contains about 15 per cent neo-b. When all-trans retinene is irradiated in the presence of isomerase, the rate of formation of neo-b is increased about 5 times, and the pseudoequilibrium shifted so that the mixture now contains about 32 per cent neo-b. The isomerase is specific for all-trans and neo-b retinene. It does not act on two other cis isomers of retinene, nor on all-trans or neo-b vitamin A. The role of the isomerase in vision appears to be as follows: in the light, as rhodopsin is bleached to opsin and all-trans retinene, the latter is in part converted to the neo-b isomer and stored in the pigment epithelium as neo-b vitamin A. During dark adaptation, the dominant process is the trapping by opsin of neo-b retinene supplied from stores of neo-b vitamin A, and the slow isomerase-catalyzed "dark" conversion of all-trans to neo-b retinene.

scholarly journals THE VITAMIN A OF A EUPHAUSIID CRUSTACEAN

1957 ◽  
Vol 40 (4) ◽  
pp. 627-634 ◽  
Author(s):  
George Wald ◽  
Paul K. Brown
Keyword(s):  
Absorption Spectrum ◽  
Vitamin A ◽  
Good Accord ◽  
Meganyctiphanes Norvegica ◽  
B Vitamin ◽  
Cis Isomer

The vitamin A of the euphausiid crustacean, Meganyctiphanes norvegica, consists almost wholly of the hindered cis isomer, neo-b (11-cis). In this animal vitamin A is concentrated almost entirely in the eyes; and its properties so closely resemble those of pure neo-b vitamin A as not in themselves to indicate that any other isomer is present. However, Fisher et al. (1955 b) have isolated a small fraction from this material which may be neo-c vitamin A (11, 13-dicis). The neo-b isomer was identified by its absolute absorption spectrum, the changes of absorption spectrum on isomerization, oxidation to neo-b retinene, and synthesis from the latter of rhodopsin. This identification is also in good accord with new, revised bioassays of Meganyctiphanes vitamin A by Plack et al. (1956).

scholarly journals REVIEWING THE THERAPEUTIC COMBINATION OF MULTIVITAMINS

2021 ◽  
Vol 5 (9) ◽  
Author(s):  
Bharat Kwatra ◽  
Chelsea Rumao ◽  
Sherin Layanal ◽  
Vaishnav Pillai
Keyword(s):  
Vitamin D ◽  
Vitamin A ◽  
Vitamin C ◽  
Vitamin B ◽  
Therapeutic Effects ◽  
Pharmacological Effects ◽  
Combination Therapies ◽  
Metabolic Activities ◽  
Healthy Functioning ◽  
B Vitamin

Vitamins are micronutrients which form an essential part of our diet. They are needed for healthy functioning of metabolic activities, some forms of vitamin form basis for our immunity and bone building. Usually essential nutrients cannot be synthesised in our bodies, hence we need to obtain them from our diet. Many Vitamin groups have been studied extensively for the pharmacological effects. Many studies have proved the effectiveness of combination therapies of vitamins with other medication for treatment of various diseases. This review presents all the studies conducted to prove the therapeutic effects of vitamins. Keywords: Multivitamins, Vitamin A, Vitamin B, Vitamin C, Vitamin D, Ginseng, Niacinamide, Antibiotics, Cefuroxime, DAV Therapy.

The Morphology of Vacuolated Cells in the Liver Following Administration of Vitamin A.

1973 ◽  
Vol 31 ◽  
pp. 408-409
Author(s):  
Odell T. Minick ◽  
Hidejiro Yokoo ◽  
Fawzia Batti
Keyword(s):  
Electron Microscopy ◽  
Body Weight ◽  
Vitamin A ◽  
Light And Electron Microscopy ◽  
Liver Cells ◽  
Prominent Feature ◽  
Vascular Space ◽  
Vacuolated Cell ◽  
Vacuolated Cells ◽  
Vacuolated Cytoplasm

Vacuolated cells in the liver of young rats were studied by light and electron microscopy following the administration of vitamin A (200 units per gram of body weight). Their characteristics were compared with similar cells found in untreated animals.In rats given vitamin A, cells with vacuolated cytoplasm were a prominent feature. These cells were found mostly in a perisinusoidal location, although some appeared to be in between liver cells (Fig. 1). Electron microscopy confirmed their location in Disse's space adjacent to the sinusoid and in recesses between liver cells. Some appeared to be bordering the lumen of the sinusoid, but careful observation usually revealed a tenuous endothelial process separating the vacuolated cell from the vascular space. In appropriate sections, fenestrations in the thin endothelial processes were noted (Fig. 2, arrow).

The Effect of Vitamin A on the Intermittent Nitrogen Dioxide Gas Exposure in Hamsters

1976 ◽  
Vol 34 ◽  
pp. 176-177
Author(s):  
J.C.S. Kim ◽  
M.G. Jourden ◽  
E.S. Carlisle
Keyword(s):  
Electron Microscopy ◽  
Vitamin A ◽  
Nitrogen Dioxide ◽  
Chronic Exposure ◽  
Light And Electron Microscopy ◽  
Specific Effect ◽  
Deficient Diet ◽  
Intermittent Exposure ◽  
Hypovitaminosis A ◽  
Gas Exposure

Chronic exposure to nitrogen dioxide in rodents has shown that injury reaches a maximum after 24 hours, and a reparative adaptive phase follows (1). Damage occurring in the terminal bronchioles and proximal portions of the alveolar ducts in rats has been extensively studied by both light and electron microscopy (1).The present study was undertaken to compare the response of lung tissue to intermittent exposure to 10 ppm of nitrogen dioxide gas for 4 hours per week, while the hamsters were on a vitamin A deficient diet. Ultrastructural observations made from lung tissues obtained from non-gas exposed, hypovitaminosis A animals and gas exposed animals fed a regular commercially prepared diet have been compared to elucidate the specific effect of vitamin A on nitrogen dioxide gas exposure. The interaction occurring between vitamin A and nitrogen dioxide gas has not previously been investigated.

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