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1.
Summary 1. The amounts of glucofructans in 15 species of plants of the genusAllium L. growing in Central Asia have been studied.2. The polydispersity of all the glucofructans isolated has been established. Fractionation of the glucofructan fromA. sativum L. yielded homogeneous fractions with mol. wt. 1900 and 5000. On the basis of their IR spectra and the results of periodate oxidation, they have been assigned to the glucofructans of the inulin type.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 137–142, March–April, 1979.  相似文献   

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Water-soluble polysaccharides and pectin substances have been isolated from various organs ofA. neglectus and their quantitative amounts and monosacchardie compositions have been determined. Native acetylated glucomannans (A, B, and C) containing 13, 15, and 20% of acetyl groups and being homogeneous according to the results of gel chromatography have been isolated from the roots. On the basis of the results of periodate oxidation, methylation, and IR spectroscopy it has been established that the neutral polysaccharides of the roots ofA. neglectus is a mixture of three glucomannans consisting of β-1→4 linear-bound D-gluco- and D-mannopyranose residues.  相似文献   

4.
Efficacy of Serratia marcescens for pigment production and biological activity was investigated. Natural substrates like sweet potato, mahua flower extract (Madhuca latifolia L.), and sesam at different concentrations were taken. As a carbon source microorganism favored potato powder was followed by sesam and mannitol, and as nitrogen source casein hydrolysate was followed by yeast and malt extract. The effect of inorganic salts on pigment production was also studied. At final optimized composition of suitable carbon, nitrogen source, and trace materials and at suitable physiological conditions, prodigiosin production was 4.8 g L?1. The isolated pigment showed antimicrobial activity against different pathogenic bacteria and fungi. Extracted pigment was characterized by spectroscopy, Fourier transform infrared (FTIR), and thin layer chromatography (TLC) which confirm production of biological compound prodigiosin. This study suggests that use of sweet potato powder and casein can be a potential alternative bioresource for commercial production of pigment prodigiosin.  相似文献   

5.
Water-soluble polysaccharides and pectin substances have been isolated from various organs ofA. neglectus and their quantitative amounts and monosacchardie compositions have been determined. Native acetylated glucomannans (A, B, and C) containing 13, 15, and 20% of acetyl groups and being homogeneous according to the results of gel chromatography have been isolated from the roots. On the basis of the results of periodate oxidation, methylation, and IR spectroscopy it has been established that the neutral polysaccharides of the roots ofA. neglectus is a mixture of three glucomannans consisting of -14 linear-bound D-gluco- and D-mannopyranose residues.Deceased.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 702–706, November–December, 1981.  相似文献   

6.
Summary The water-soluble polysaccharides of the rhizomes of thePolygonatum sewerzowii Regl. have been studied. A method has been developed for separating the polysaccharide fraction. A new native acetylated glucomannan has been isolated which has been called severan and consists of manno- and glucopyranose residues linked with one another by -1 4 bonds in a ratio of 15.4:1.Institute of the Chemistry of Plant Substances, Academy of Plant Substances of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 555–559, September–October, 1978.  相似文献   

7.
A non-photoreactivable mutant of Serratia marcescens   总被引:1,自引:0,他引:1  
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Human calcitonin. I. Isolation and characterization   总被引:1,自引:0,他引:1  
Two highly active calcitonin peptides, M with 32 amino acids, and D a dimer of M, were isolated from a large human mediastinal C cell tumour. D can easily be transformed into M by the action of 1N ammonia; D and M afford two different sulphoxides, but all four peptides yield the same product upon oxidation with performic acid. Both D and M have a potency of about 120 MRC units/mg dry weight; their sulphoxides, by contrast, are almost inactive. Tryptic digestion of M produces an N-terminal octadecapeptide (TrI) and a C-terminal tetradecapeptide (TrII), the latter being also obtained from D. Amino acid analysis and other analytical data are presented. The structure of the human calcitonin peptides D and M is thus very different from that of porcine α-thyrocalcitonin.  相似文献   

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The polysaccharides of the tuberous roots ofBiebersteinia multifida D. C. have been isolated and characterized. The neutral polysaccharide consists of a mixture of three glucans — A, B, and C — with molecular weights of 4100, 2200, and 1100, respectively, formed by D-glucopyran residues linked by α bonds.  相似文献   

12.
Prodigiosins (prodiginines) are a class of bacterial secondary metabolites with remarkable biological activities and color. In this study, optimized production, purification, and characterization of prodigiosin (PG) from easily accessible Serratia marcescens ATCC 27117 strain has been achieved to levels of 14 mg/L of culture within 24 h. Furthermore, environmentally friendly bromination of produced PG was used to afford both novel mono- and dibrominated derivatives of PG. PG and its Br derivatives showed anticancer potential with IC50 values range 0.62–17.00 µg/mL for all tested cancer cell lines and induction of apoptosis but low selectivity against healthy cell lines. All compounds did not affect Caenorhabditis elegans at concentrations up to 50 µg/mL. However, an improved toxicity profile of Br derivatives in comparison to parent PG was observed in vivo using zebrafish (Danio rerio) model system, when 10 µg/mL applied at 6 h post fertilization caused death rate of 100%, 30% and 0% by PG, PG-Br, and PG-Br2, respectively, which is a significant finding for further structural optimizations of bacterial prodigiosins. The drug-likeness of PG and its Br derivatives was examined, and the novel Br derivatives obey the Lipinski’s “rule of five”, with an exemption of being more lipophilic than PG, which still makes them good targets for further structural optimization.  相似文献   

13.
The production of biosurfactant, a surface-active compound, by two Serratia marcescens strains was tested on minimal culture medium supplemented with vegetable oils, considering that it is well known that these compounds stimulate biosurfactant production. The vegetable oils tested included soybean, olive, castor, sunflower, and coconut fat. The results showed a decrease in surface tension of the culture medium without oil from 64.54 to 29.57, with a critical micelle dilution (CMD−1) and CMD−2 of 41.77 and 68.92 mN/m, respectively. Sunflower oil gave the best results (29.75 mN/m) with a CMD−1 and CMD−2 of 36.69 and 51.41 mN/m, respectively. Sunflower oil contains about 60% of linoleic acid. The addition of linoleic acid decreased the surface tension from 53.70 to 28.39, with a CMD−1 of 29.72 and CMD−2 of 37.97, suggesting that this fatty acid stimulates the biosurfactant production by the LB006 strain. In addition, the crude precipitate surfactant reduced the surface tension of water from 72.00 to 28.70 mN/m. These results suggest that the sunflower oil’s linoleic acid was responsible for the increase in biosurfactant production by the LB006 strain.  相似文献   

14.
硫酸化高山红景天多糖(RSASL)的制备及鉴定   总被引:11,自引:0,他引:11  
从高山红景天中分离出一种酸性杂多糖(RSA).该多糖由阿拉伯糖(Ara)、鼠李糖(Rha)、半乳糖(Gal)、木糖(Xyl)、葡萄糖(Glc) 与半乳糖醛酸(GalA)组成,其单糖摩尔比为1.00∶3 .23∶0 .26∶0 .34∶0 .84∶10.24.用氯磺酸-吡啶法制备硫酸化高山红景天多糖(RSASL).用离子色谱法测定RSASL 中S的质量分数为11.01% ,其硫酸基取代度为0.85.用红外光谱,紫外光谱,Sepharose CL-4B柱层析,激光解吸电离飞行时间质谱等方法鉴定,RSASL均显示了多糖硫酸酯的特征  相似文献   

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The polysaccharides of the tuberous roots ofBiebersteinia multifida D. C. have been isolated and characterized. The neutral polysaccharide consists of a mixture of three glucans — A, B, and C — with molecular weights of 4100, 2200, and 1100, respectively, formed by D-glucopyran residues linked by bonds.Deceased.Institute of the Chemistry of Plants Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 755–757, November–December, 1985.  相似文献   

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A polysaccharide possessing pronounced direct-action anticoagulant activity has been isolated from the epigeal part ofLagochilus usunachmaticus.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. 5, pp. 690–692, September–October, 1997.  相似文献   

19.
Two new products of hydrolysis of cyclophosphamide in water at 100°, N-(2-chloroethyl)-N' -(3-phosphatopropy l)ethylenediamine and N-(2-hydroxyethyl)-N -(3-phosphatopropyl)ethylene-diamine, have been isolated after 30 minutes, and 6 hours of reaction times, respectively. These products have been shown to be intermediates leading to the formation of N-(2-hydroxyethyl)-N'-(3-hydroxypropyl)ethylenediamine, the principal ultimate product of cyclophosphamide hydrolysis. The nature of these new products supports the previously postulated mechanism involving an intramolecular alkylation as the initial step in the hydrolytic process although the pathway appears to be an unlikely model for the metabolic transformations of cyclophosphamide in vivo.  相似文献   

20.
The syntheses of a number of o-acylstyrenes (o-acetyl through o-hexanoyl) have been described. Polymerizations were carried out radically at 80°C under high vacuum. While all polymerizations conform to the usual free radical kinetic scheme, rates are sensitive to the nature of the acyl substituent, and this has been ascribed to steric effects, the bulky substituents adjacent to the propagating radicals inhibiting the approach of monomer. Molecular weight and polydispersity data indicate that both combination and disproportionation occur during terminations. UV spectra consist of two absorptions associated with n → π* and π → π* transitions. 13C-NMR spectra have been analyzed and assignments made on the basis of spectral editing. The considerable variation of glass transition temperatures has been accounted for in terms of a combination of steric and dipolar interactions.  相似文献   

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