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1.
A mannan has been isolated from the bulbs ofUngernia ferganica Vved., and its qualitative chemical composition, the nature of the bond between the hexose residues, and the form of the molecule have been determined. It has been established that the mannan is a relatively nontoxic compound and exhibits a pronounced hypolipidemic activity both in intact animals and in animals with experimental hyperlipidemia.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Republic of Uzbekistan, Tashkennt, fax (3712) 89 14 75. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 690–692, September–October, 1996. Original article submitted February 14, 1996.  相似文献   

2.
A mannan having a linear structure and containing -1 4-bound D-mannopyranose residues in the chain has been isolated from the bulbs ofUngernia oligostroma M. Pop et Vved. X-ray and electron microscope studies have been made of the mannan and its derivatives. From the x-radiographic point of view the mannan and its derivatives are amorphous. At the supermolecular level the mannan possesses an amorphous finely disperse structure with loose packing of the particles. In the acylated mannan a tendency to the formation of the characteristic laminar structure elements are observed. Such laminae may be fairly thin (down to a thickness of 0.1–0.3 µm).Institute of the Chemistry of Plant Substances, Uzbek SSR Academy of Sciences, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 327–330, May–June, 1989.  相似文献   

3.
The group carbohydrate composition of the bulbs ofAllium coeruleum Pall. have been studied. The qualitative and quantitative compositions of the glucofructans, pectin substances, and hemicelluloses isolated have been determined and their physicochemical characteristics are reported. A general formula for the glucofructan fromA. coeruleum bulbs is given on the basis of the results of periodate oxidation, methylation, and IR, and13C NMR spectroscopy.Deceased.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 17–21, January–February, 1985.  相似文献   

4.
The production of yeast cell wall mannan degrading -mannosidase was studied in shake flask experiments as well as in a highly instrumented, computer-coupled bioreactor. The enzyme is predominantly excreted into the culture liquid upon submerged cultivation on yeast mannan. Only low activities were detected with mannose or glucose as carbon source whereas the enzyme formation was totally repressed by glycerol. The amount of enzyme produced is proportional to the microbial biomass formed.Carbon-unlimited cultivation on mannose, the primary product of enzymic digestion, resulted in a specific growth rate of 0.10h–1, a specific oxygen uptake rate ·h and a respiratory quotient ofRQ=1.0. Addition of yeast mannan (0.5%) to nutrient-depleted bacterial cells resulted in an almost complete utilization of this substrate, with 55% of substrate carbon being converted to biomass and 37% to carbon dioxide. The yield coefficient on mannan wasY x/s =0.51 (g/g). Enzyme formation started with a delay of 30–40 min and stopped with termination of growth. Due to the increased production of mannose by the action of the enzyme the specific growth rate increased from 0.05 to 0.10 h–1, thus enabling computations of maintenance and yield coefficients for oxygen and carbon dioxide metabolism.
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5.
A new glycoalkaloid, edpetinosine, has been isolated fromPetilium eduardi bulbs, and its structure has been established on the basis of chemical transformations and spectral characteristics.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Republic of Uzbekistan, Tashkent, fax (3712) 40 64 75. Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 617–619, July–August, 1997.  相似文献   

6.
Acetobacter xylinum was cultured in Schramm–Hestrin medium containing pectin (pectin medium), xylan (xylan medium), or glucomannan (mannan medium). X-ray diffractometry revealed that xylan and glucomannan affected the size of the cellulose crystals and their d-spacing values. Solid-state cross polarization magic angle spinning carbon-13 nuclear magnetic resonance spectroscopy indicated that the ratio of cellulose I was reduced by the addition of polysaccharides. These effects were more remarkable on the cellulose in the mannan medium than that in the xylan medium, and were scarcely observed in the pectin medium. Electron diffraction analysis revealed that these effects on hemicelluloses along cellulose microfibrils are continuous in the mannan medium and discontinuous in the xylan medium. These findings suggest that the uronic acid in the polysaccharides prevents interactions with cellulose leading to alterations of the structure of the cellulose crystal.  相似文献   

7.
The carbohydrate components of the bulbs ofAllium cepa L. (white variety) have been characterized. It has been established that the main carbohydrate component is the ethanol-soluble fraction. Information has been obtained on the elementary compositions and origin of a number of fragments in the mass spectrum of the peracetate of 1F-kestose.Deceased.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 174–178, March–April, 1985.  相似文献   

8.
The carbohydrate compositions of all the organs ofAllium suvorovii Rgl have been determined and it has been established that the bulk of the fructose accumulates in its bulbs. The dynamics of the accumulation of glucofructans in the bulbs has been studied and it has been found that this accumulation is a maximum in the dormancy stage.Institute of Chemistry of Plant Substances, Uzbekistan Academy of Sciences, Tashkent. Translated from Khimiya Prirodnykh Soedienii, No. 6, pp. 622–624, November–December, 1992.  相似文献   

9.
Two new alkaloids — petine and petine N-oxide — have been isolated from the bulbs of Petilium eduardi. Their structures have been established on the basis of spectral characteristics and chemical transformations.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Republic of Uzbekistan, Tashkent, FAX (3712) 89-14-75. Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 524–528, July–August, 1994.  相似文献   

10.
Water-soluble polysaccharides have been isolated from the bulbs ofAllium longicuspis Rgl. By fractionating the combined water-soluble polysaccharides, homogeneous polysaccharides with molecular weights of 15,500 and 5100 have been isolated. It has been shown by spectral and chemical methods that they consist of glucofructans of a mixed type containing glycosidic bonds of the inulin (2 1) and levan (26) types in a ratio of 2.1:1.Deceased.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 703–707, November–December, 1984.  相似文献   

11.
From a mixture of bases from the epigeal part and the bulbs ofPetilium raddeana (Rgl.) Vved. ex Pazij, a new base petisidinine has been isolated with mp 290–292°C (decomp.), composition C27H39NO3 (I). On the basis of the physicochemical properties of the alkaloid and a correlation with petisine, the structure and configuration of petisidinine have been established as those of 3-hydroxy-20-(5-hydroxy-3-methylpyridin-6-yl)-5-pregnan-6-one.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Trashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 747–749, November–December, 1983.  相似文献   

12.
Summary The UV spectra in concentrated sulfuric acid of hederagenin and oleanolic acid and their glycosides has been studied. For analytical purposes it is proposed to use the extremum at a wavelength of 405 nm, which is distinguished by constancy of position and intensity of absorption for the genins and their glycosides.A spectrophotometric method is proposed for the determination of the triterpene glycosides in a preparation from the bulbs ofLeontice ewersmannii Bge.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 220–227, March–April, 1977.  相似文献   

13.
The structure of an extracellular mannan formed by the yeastBullera tsugae has been studied. It has been shown that the repeating unit of this polysaccharide contains -(13)- and -(14)-bound D-mannopyranose residues in equimolar ratio. A comparison has been made of the polymer under investigation with the extracellular mannan from a yeast of the genusRhodotorula. Leningrad Institute of Pharmaceutical Chemistry. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 746–750, November–December, 1985.  相似文献   

14.
Summary In addition to the known spirostans neoagigenin and alliogenin, we have isolated from the skins of the bulbs ofAllium turcomanicum Rgl. a new steroid sapogenin — neoalliogenin, which is (25S)-5-spirostan-2, 3, 5, 6-tetraol.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 823–826, November–December, 1977.  相似文献   

15.
The alkaloids imperialine, imperialone, peumisine, petiline, petilidine, and the new bases petisine (I) and petisinine (III) have been isolated from bulbs ofPetilium raddeana (Regl.) Vved. On the basis of spectral characteristics and passages to a known compound, the structure of 3-hydroxy-22(N)-22,26-iminocholestane-6,23-dione has been established for (I) and petisine 3-glucopyranoside for (III).Institute of the Chemistry of Plant Substances of the Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 616–619, September–October, 1981.  相似文献   

16.
From the WSPS-I of the bulbs with roots ofJuno drepanophylla, 15 fractions have been isolated by fractionation on DEAE-cellulose. Fractions 1 and 2 together made up 53% of the total weight of the fractions. Fraction 1 proved to be homogeneous on ultracentrifugation, on passage through Sepharose-4B, and on high-pressure LC. The results of the analysis of the methylated product of fraction 1 differed little from those for the initial polysaccharide.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 415–418, July–August, 1986.  相似文献   

17.
The effect of solvent polarity versus specific C–HO contacts on the vibrational νC–H mode is studied using CHCl3 as a model system. Ab initio SCI–PCM calculations show that the overall shift of the νC–H band, sometimes ascribed to the C–HO hydrogen bonding, can in fact be explained by the electrostatic interaction with a dielectric environment. The presence of a new νC–H band – assigned to the C–HO bonded forms – remains as the most reliable evidence of C–HO hydrogen bonding.  相似文献   

18.
Conclusions A new alkaloid korsine, C27H43O3N, has been isolated from the bulbs ofKorolkowia sewerzowii. Its structure and configuration have been established on the basis of a study of its chemical properties and IR, UV, NMR, and mass spectra.Khimiya Prirodnykh Soedinenii, Vol. 4, No. 3, pp. 161–168, 1968  相似文献   

19.
The equilibrium structures, binding energies, and vibrational spectra of the clusters CH3F(HF)1 n 3 and CH2F2(HF)1 n 3 have been investigated with the aid of large-scale ab initio calculations performed at the Møller–Plesset second-order level. In all complexes, a strong C–FH–F halogen–hydrogen bond is formed. For the cases n = 2 and n = 3, blue-shifting C–HF–H hydrogen bonds are formed additionally. Blue shifts are, however, encountered for all C–H stretching vibrations of the fluoromethanes in all complexes, whether they take part in a hydrogen bond or not, in particular also for n = 1. For the case n = 3, blue shifts of the ν(C–H) stretching vibrational modes larger than 50 cm−1 are predicted. As with the previously treated case of CHF3(HF)1 n 3 complexes (A. Karpfen, E. S. Kryachko, J. Phys. Chem. A 107 (2003) 9724), the typical blue-shifting properties are to a large degree determined by the presence of a strong C–FH–F halogen–hydrogen bond. Therefore, the term blue-shifted appears more appropriate for this class of complexes. Stretching the C–F bond of a fluoromethane by forming a halogen–hydrogen bond causes a shortening of all C–H bonds. The shortening of the C–H bonds is proportional to the stretching of the C–F bond.  相似文献   

20.
In this article, blank anionic poly(-caprolactone)-poly(ethylene glycol)-poly(-caprolactone) (PCEC) and anionic mannan modified PCEC (MPCEC) nanoparticles with nearly the same particle size and zeta potential were prepared by emulsion solvent evaporation method. Human basic fibroblast growth factor (bFGF) was absorbed onto anionic nanoparticles surface due to electrostatic interaction. The obtained bFGF-nanoparticles complexes were injected subcutaneously into C57BL/6 mice at 20 μg of bFGF/dose on week 0, 1, 2 and 3. The mice serum was collected on week 4, and bFGF-specific autoantibody total IgG, IgG1 and IgG2a titer in serum was determined by ELISA. The results indicated that the autoantibody IgG, IgG1 and IgG2a titer of the mice immunized by bFGF–MPCEC complexes were higher than that immunized by either bFGF–PCEC or bFGF–Alum. This phenomenon might be due to that mannan functionalized MPCEC nanoparticles could be targeted to dendritic cells (DCs) to improve humoral immunity. The prepared anionic mannan modified PCEC nanoparticles (MPCEC) might have great potential application in vaccine delivery systems.  相似文献   

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