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1.
A new taxoid, 10-deacetyltaxezopidine G, and a previously reported compound (Taxezopidine G) have been isolated from the needles and young stems of Taxus baccata L. growing in Iran, and the structures were determined on the basis of spectroscopic data. These two compounds were not previously encountered in Taxus baccata L. species. Published in Khimiya Prirodnykh Soedinenii, No. 4, pp. 321–322, July–August, 2006.  相似文献   

2.
The protein composition and the kinetics of the quantitative changes in the various protein fractions during the ontogenesis of protoplast and hybrid cultures ofTrichoderma harzianum have been studied. In the exponential growth phases of both cultures the highest amount of protein was contained in the water-soluble (33.0–33.2%) and salt-soluble (31.0–32.0%) fractions. The protein contents of the water-soluble fractions of the cultures studied were similar to those in meat and clover and were 3.5 times greater than in yeast.Institute of Microbiology, Academy of Sciences of the Republic of Uzbekistan, Tashkent, fax (3712) 41 71 29. Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 209–211, March–April, 1998.  相似文献   

3.
Summary To measure the five classical protein fractions in human serum several electrophoretic techniques are available. Besides separation on cellulose acetate membrane or agarose gel, capillary zone electrophoresis (CZE) may be a useful analytical alternative in clinical routine. We have compared the Dionex CES I capillary electrophoresis system with that of the Olympus Fractoscan using specimens submitted for routine analysis. For clinical evaluation 102 samples from patients with various diseases have been analysed. Serum protein fractions were judged on separation performance, precision and the regression method ofBablok-Passing. Regression analysis revealed variable agreement between both methods with a slope ± intercept of 2.10–0.52 (α1-fraction) and 1.0–0.20 (α2-fraction) as worse and best, resectively; and the coefficient of variation of migration time: 5.9 %–6.8 % (between-run imprecision). Differences in the comparison of fractions are mainly caused by the improved resolution of CZE; e.g. one β-globulin peak on cellulose acetate is separated into two distinct protein fractions in CZE, including more detailed diagnostic information—as is also the case with γ-fraction. In some cases monoclonal gammopathy with low concentrations of immunglobulin clone can only be detected in CZE, whereas the cellulose acetate membrane (CAME) electropherogram is inconspicuous. The within-run precision (N=18) gave coefficients of variation of peak areas 1.3–5.9 % (CZE) and 1.0–3.8 % (cellulose acetate membrane). This is the first time that a complete clinical evaluation of CZE serum protein fraction analysis has been performed. CZE with its higher resolution and hence more detailed diagnostic information in some cases, showed good separation patterns, precision and correlation. Interchangeability of results showed that this CZE method is well suited for analysis of serum protein fractions in clinical routine. Presented at the 21st ISC held in Stuttgart, Germany, 15th–20th September, 1996.  相似文献   

4.
The accumulation dynamics of cellulolytic enzymes in culture media of the basidiomycete fungi Panus tigrinus, Pleurotus ostreatus, Fomes fomentarus, and the micromycete Aspergillus terreus were studied during a long incubation period. It was found that A. terreus was the most active producer of cellulolytic enzymes among the studied fungi. Two protein fractions with cellulase activity were isolated using gel filtration and ion-exchange chromatography. PAAG electrophoresis showed that fraction-I consisted of four components; fraction-II, an electrophoretically homogeneous protein. __________ Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 489–491, September–October, 2007.  相似文献   

5.
Polysaccharides isolated by successive extraction with water at 20 and 80°C from freshly collected and dried alga T. crinitus were compared. It was shown that the yield of polysaccharides from freshly collected alga was 40–44%; from dried material, less than 25%. It was found that the amount of extracted polysaccharides and their molecular weights decreased upon storage of dried alga for three years. Polysaccharides isolated from freshly collected and dried alga had identical structures and were a mixture of κ/β- and a new X-type of carrageenan. It was shown that protein, the amount of which reached 24% in the extracts obtained at 20°C, was strongly bound to the carrageenan. The amino-acid compositions of the proteins associated with the polysaccharides isolated at 20 and 80°C were identical and had an elevated content of serine, glutamic acid, glycine, and alanine.  相似文献   

6.
The aim of this work is to show new advances in the analytical methods developed in the frame of the ban of processed animal by-products in compound feed that is currently applied within the European Union. With this aim, studies to develop a quantitative near infrared microscopy (NIRM) approach have been undertaken in order to fulfil future requirements of European legislation like the introduction of tolerance levels that would require for official control purposes the availability of specific quantitative methods. The capabilities of the NIRM method have been improved; no sample preparation is required and the acquisition parameters are optimised. Both the gross and the fine fractions of the samples are considered; the reflexion mode was used to analyse the gross raw fraction and the transmission mode was chosen to analyse the fine raw fraction. Parameters for reflexion analyses were already fixed in our previous studies while those of transmission mode have been determined in the present study. Because particles are too small, it is difficult to mark them; spectra were collected using the mapping technique. Quantitative analyses have been carried out for different percentages of adulteration (0.5, 1, 2 and 5%). Results were depending on the particle size distribution of the feed and of the fish meal which led to experimental values of adulteration varying between 0.13–0.92%, 0.93–3.7%, 2.42–5.83% and 1.95–9.39% for theoretical percentages of adulteration equal to 0.5, 1, 2 and 5%, respectively. The established protocol with the key parameters proposed has to be considered for the development of an accurate method of quantification.  相似文献   

7.
Thielavia terrestris 255B, a thermophilic ascomycete, produced two major forms of xylanase with pIs of 4.6 (xylanase I) and 6.1 (xylanase II). The latter enzyme could be purified to > 99% homogeneity using anion-exchange chromatography and gel filtration. Xylanase II had a mol wt of 25.7 kDa (SDS-PAGE) and a pH and a temperature optimum of 3.6–4.0 and 60–65°C, respectively. The ratio of the enzyme’s activity against xylan and carboxymethylcellulose was 500–1000 to 1, indicating a possible application of this enzyme in biobleaching processes. The amino acid sequence of this protein is being determined, and initial data suggest that the enzyme belongs to a group of low-mol wt xylanases that have been isolated from both bacteria and fungi.  相似文献   

8.
Two steroid glycosides belonging to the furostan series — funkioside B and protodioscin — have been isolated from the seeds of the plantMelilotus tauricus (Bieb.). Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 766–770, November–December, 1994.  相似文献   

9.
Studies on the extracellular enzymes ofCoriolus versicolor have resulted in the isolation and purification of several proteins that have the potential to act as redox enzymes.C. versicolor was cultured on a glucose-amino acid medium in a large-scale fermenter (60 L) with 2,5-xylidine added to induce the production of extracellular laccase. Proteins were precipitated from the growth medium with ammonium sulfate, and separated by ion-exchange chromatography on DEAE-Sephadex. Further separation of glycoproteins was achieved by affinity chromatography on Concanavalin-A-Sepharose. Polyacrylamide gel electrophoresis on SDS (sodium dodecyl sulfate) and LDS (lithium dodecyl sulfate) gels, isoelectric focusing, and chromatofocusing have been used to establish purity of the proteins and their isoelectric points. Laccase B has been isolated and separated into five fractions by chromatofocusing, with isoelectric points of the fractions varying between pH 4.5 and 6.5. The relative specificity of these fractions towards monophenolic and diphenolic substrates has been investigated. Laccase A was found to differ from laccase B in showing only two bands on isoelectric focusing, with isoelectric points between pH 3.0 and 3.5. Two other proteins isolated from the growth medium were both hemecontaining proteins with interesting spectral properties. One was a “peroxidasetype” heme that could bind carbon monoxide to the iron in the heme, suggesting that the heme may bind oxygen and so function as an oxidase. It reacted with hydrogen peroxide to liberate hydroxyl radicals, but this reaction with hydrogen peroxide resulted in the destruction of the heme center. The real role of this protein is unclear, but several possibilities will be investigated. The second heme-containing protein isolated had different spectral properties from the “peroxidase-type” heme previously described. It had spectral characteristics of a b-type cytochrome in association with a flavin prosthetic group. It appeared to have some similarities to cellobiose oxidase, a heme flavoprotein previously isolated fromSporotrichum pulverulentum, although its molecular weight was 50,100 daltons compared with the 93,000 reported for cellobiose oxidase. Further characterization of this protein will be described.  相似文献   

10.
We have performed a detailed characterization and identification of wheat gluten proteins obtained from the Teal variety of Canadian hard red spring wheat. RP-HPLC separation of the sample into 35 fractions has reduced the spectral complexity; this was followed by MALDI mass spectrometry (MS), which showed the presence of six or fewer resolved protein components above 20 kDa in each RP-HPLC fraction, giving a total of 93 MS resolved peaks. These included 17 peaks in the ω-gliadin fractions (F1–4), 12 in the high molecular weight (HMW) glutenin subunit fractions (F5–8), 59 in the α- and β-gliadins and low molecular weight (LMW) glutenin subunit fractions (F9–31) and 5 peaks in the γ-gliadin fractions (F32–35). Peptide maps of tryptic digests of HPLC fractions were obtained from a tandem quadrupole time-of-flight mass spectrometer (MALDI QqTOF MS) and were submitted to the ProFound search engine. HMW glutenin subunits including Ax2*, Dx5, Bx7, and Dy10 (consistent with the known profile of Teal), and LMW glutenin subunits including six from group 3 type II and 1 from group 2 type I, were identified with reasonable sequence coverage from HPLC fraction 5, 7, 17, and 18. The identities of the peptides attributed to selected gluten proteins were confirmed using MS/MS with BioMultiView to match the predicted and measured partial amino acid sequences. Because of incomplete wheat DNA databases, many wheat gluten proteins could not be identified. These results suggest that the combination of RP-HPLC with MS and MS/MS techniques is a promising approach for the characterization of wheat gluten proteins.  相似文献   

11.
Two steroid glycosides belonging to the spirostan series — trillin and dioscin — have been isolated from the seeds of the plantMelilotus tauricus (Bieb.) Ser. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 770–772, November–December, 1994.  相似文献   

12.
A sorbent highly specific forVerticillium proteins has been obtained from BrCN-Sepharose and rabbit immunoglobulins. By affinity chromatography using this sorbent a protein immunologically similar to the proteins of the mycelium of the fungusV. dahliae has been isolated from cotton seeds of the Tashkent-1 variety. The molecular mass of the protein has been determined, and its proteolytic activity has been established. Institute of the Chemistry of Plant Substances, Academy of Sciences of the Republic of Uzbekistan, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 746–749, September–October, 1993.  相似文献   

13.
Lepenine and the new alkaloid lepenine N-oxide have been isolated from the epigeal part ofAcontium kirinense. Institute of the Chemistry of Plant Substances, Academy of Sciences of the Republic of Uzbekistan, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 734–736, September–October, 1993.  相似文献   

14.
Effects of the two most widespread sample preparation techniques on the d,l-enantiomer ratio of extracted selenomethionine were monitored through the analysis of the certified reference material selenium-enriched yeast and the isolated protein fraction of high selenium monkeypot nut. The extracted selenomethionine (SeMet) fractions were orthogonally cleaned up with anion exchange chromatography before carrying out the enantiomer-specific detection to increase the robustness and the efficiency of the subsequent o-phthal-aldehyde and n-isobutyril-cysteine-based derivatisation process and reversed phase-high-performance liquid chromatography-inductively coupled plasma mass spectroscopy (ICP-MS) detection. The two techniques, namely methanesulphonic acid (MSA) based digestion and proteolytic digestion with protease XIV, resulted in significantly different ratio of d,l-selenomethionine with the final results of 2.2–2.7% and 0.5–0.6% of d-SeMet, respectively. The study revealed significant differences in the ICP-MS-related sensitivity of the derivatised selenomethionine enantiomers, which calls attention to the quantification of this selenoamino acid after MSA hydrolysis.  相似文献   

15.
The azaspiracids are a family of lipophilic polyether marine biotoxins that have caused a number of human intoxication incidents in Europe since 1995 after consumption of contaminated shellfish (Mytilus edulis). Levels of azaspiracids in shellfish for human consumption are monitored in accordance with EU guidelines: only shellfish with less than 160 μg kg−1 are deemed safe. The limited availability of commercially available standards for azaspiracids is a serious problem, because validated LC–MS methods are required for routine analysis of these toxins in shellfish tissues. The procedure described herein has been used for the separation and the isolation of four azaspiracid (AZA) toxins from shellfish, for use as LC–MS–MS reference materials. Five separation steps have been used to isolate azaspiracids 1, 2, 3, and 6. The purity of the toxins obtained has been confirmed by multiple mass spectrometric methods using authentic azaspiracid standards. The same techniques have been used for quantification of the toxins extracted. The isolation procedure involves several chromatographic purification techniques: solid-phase extraction (diol sorbent, 90% mass reduction, and 95 ± 1% toxin recovery); Sephadex size-exclusion chromatography (87% mass reduction and up to 95 ± 2% toxin recovery), Toyopearl HW size-exclusion chromatography (90% mass reduction and up to 92.5 ± 2.5% toxin recovery), and semi-preparative LC (78 ± 3% toxin recovery). The procedure effectively separates the toxins from the sample matrix and furnishes azaspiracid toxins (AZA1, AZA2, AZA3 and AZA6) of sufficient purity with an average yield of 65% (n = 5). Triple-quadrupole mass spectrometry was used for qualitative and quantitative monitoring of the isolation efficiency after each stage of the process. High-resolution mass spectrometric evaluation of the toxic isolated material in both positive and negative modes suggests high purity.  相似文献   

16.
Sum frequency generation (SFG) spectra and surface pressure–molecular area (π–A) isotherms have been obtained for mixed cholesterol–DPPC monolayers with cholesterol mole fractions, x(chol.), from 0 to 1.0, at the air–water interface, under same conditions, at 22 °C. Analysis of the spectra indicated that incorporation of cholesterol into the monolayers at 3 mN m−1 greatly increases the conformational and orientational order of the alkyl chains of DPPC, maximizing these properties at x(chol.)=0.4. Analysis also indicated that order in the mixed monolayers at 15 and 35 mN m−1 is not affected by incorporation of cholesterol. The π–A isotherms measured at 3 mN m−1 for the mixed monolayer with x(chol.)=0.4 have the largest negative deviation of the molecular area relative to those of ideal mixtures (the so-called “condensation effect” of cholesterol), indicating the most thermodynamically stable state. Comparison of results from SFG spectra and π–A isotherms explicitly proved that the condensation effect can be interpreted in terms of conformational and orientational ordering of the alkyl chains of DPPC.  相似文献   

17.
The lipid compositions of the coats and kernels of the seeds ofNepeta pannonica andLavandula vera have been studied. It has been established that the lipids of the seed coats of the two species of plants differ substantially in their composition. The lipids of the kernels ofNepeta have been found to contain free fatty acids with chain lengths of from C20 to C35. Ursolic acid and its acetate have been isolated from extracts of the seed coats ofLavandula, and dimethyladipic acid from the seed oil of this species. Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 614–620, September–October, 1980.  相似文献   

18.
Accumulation of americium (241Am) and plutonium (238,242Pu) and their distribution in cell compartments and biochemical components of the biomass of freshwater aquatic plants Elodea canadensis, Ceratophyllum demersum and Myrioplyllum spicatum and aquatic moss Fontinalis antipyretica have been investigated in laboratory experiments. Americium and plutonium taken up from water by Elodea canadensis apical shoots were mainly absorbed by structural components of plant cells (90% for 241Am; 89% for 238Pu and 82–87% for 242Pu). About 10–18% of isotope activity was recorded in the cytosol fraction. The major concentration (76–92%) of americium was bound to cell wall cellulose-like polysaccharides of Elodea canadensis, Myriophyllum spicatum, Ceratophyllum demersum and Fontinalis antipyretica, 8–24% of americium activity was registered in the fraction of proteins and carbohydrates, and just a minor concentration (<1%) in the lipid fraction. The distribution of plutonium in the biomass fractions of Elodea was similar to that of americium. Hence, americium and plutonium had the highest affinity to cellulose-like polysaccharides of cell walls of freshwater submerged macrophytes.  相似文献   

19.
Our previous study found that high-molecular-weight selenium (Se) species make up 82% of the total Se in the bean of Se-enriched soybean plants (Chan et al. 2010, Metallomics, 2(2): p. 147–153). The Se species have been commonly seen in other plants in addition to soybean, but their identities remain unresolved. The present study employs a multi-technique metallomics approach to characterize the proteins containing Se in the beans of Se-enriched soybean plants. Two main categories of proteins, maturation proteins and protease inhibitors, were found in Se-containing high-performance liquid chromatography (HPLC) fractions. The proteins were screened by two-dimensional HPLC-inductively coupled plasma mass spectrometry, size-exclusion chromatography, and anion-exchange chromatography, and the Se-containing fractions were then identified by peptide mapping using HPLC-Chip-electrospray ion trap mass spectrometry. Based on the belief that Se goes into proteins through non-specific incorporation, a new method was designed and applied for the Se-containing peptide identification. The Se-containing peptide KSDQSSSYDDDEYSKPCCDLCMCTRS, part of the sequence of protein Bowman–Birk proteinase isoinhibitor (Glycine max), was found in one of the Se-containing fractions. The nutritional value of the Se-containing proteins in Se-enriched soybeans will be an interesting topic for the future studies.  相似文献   

20.
Pectin substances have been isolated from the leaves ofUngernia tadschicorum and characterized. A galacturonan has been obtained by partial hydrolysis. On the basis of the results of IR spectroscopy and periodiate — nitric acid oxidation, its structure has been established as an α-1→4-bound polymer-homolog. Institute of the Chemistry of Plant Substances, Academy of Sciences of the Republic of Uzbekistan, Tashkent, FAX (3712) 62 73 48. Translated from Khimiya Prirodnykh Soedinenii, No. 3, 320–322, May–June, 1994.  相似文献   

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