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1.
The use of a single, commercially available column packing, TabsorbR, is described for the g. l. c. separation of a large number of different compounds. The resolution of the homologous members of the following series of compounds was achieved: (1) saturated fatty acids (C1-C18), (2) normal aliphatic saturated dlcarboxylic acids (C2-C14), (3) normal aliphatic saturated alcohols (C1-C24), (4) normal aliphatic saturated amines (C1C12), (5) the common amino acids except arginlne, histidlne and cysteine, (6) aliphatic hydrocarbons (C10-C20) and (7) monosaccharides. It should be noted that twenty-two monosaccharides including three hexosamines and two anhydrohexoses, could be resolved as aldltol acetates In a single run. In addition, galacturonic, glucuronic and lduronlc acids could be separated from one another as their 1, 4-lactones. The resolution achieved in these series of compounds was found to be consistent and highly reproducible. It is of further interest that certain Isomers of the higher fatty acids and hydrocarbons with one double bond could also be separated from the normal and saturated compounds, respectively. The applicability of “Tabsorb” for the g. l. c. separation, although noted above to be considerably broad, is by far not yet exhausted. These procedures which form the basis for the quantitative determinations of the various compounds studied as demonstrated by analysis of glycopeptldes for neutral hexoses and proteins for the amino acids, can readily be adapted to preparative methods. From the biochemical point of view “Tab-sorb” is an extremely versatile column packing in that it can be used for the identification of many of the common building blocks of natural products.  相似文献   

2.
Separation and determination of the optical isomers of chrysanthemic acid has been carried out by gas chromatography. The diastereoisomeric esters of chrysanthemic acid with l-menthol were separated on a column of 2% QF-1 coated on Chromosorb W. d-trans, l-trans and dl-cis Chrysanthemic acids were resolved but d-cis and l-cis acids were not separatable from one another on any column tested. These isomers of chrysanthemic acid were not isomerized during esterification and gas chromatographic operation, and their ratios were determined from their peak area ratios. The l-bornyl esters of the isomers of chrysanthemic acicf were not so easily separatable as the l-menthyl esters.  相似文献   

3.
Separation of asymmetric amines by derivatization to the corresponding amides with N-trifluoroacetyl-L-prolyl chloride was carried out by gas-liquid chromatography, and the structure-separation relationship was studied. For a series of ring-substituted 1-phenyl or naphthylalkylamines, diastereoisomeric amides were better resolved on a relatively polar column than on a nonpolar column with the L(+) forms eluted before the L(?) forms and the separation was poorer as the alkyl group attached to the asymmetric carbon atom was varied from isopropyl to methyl to n-propyl to isobutyl. On the contrary, for another series of ring-substituted 1,2-diphenylethylamines, the isomeric amides were better resolved on a nonpolar column than on a polar column, the L(+) forms being eluted with longer retention than the L(?) forms, and the separation was better when the alkyl group substituted for a hydrogen of the phenyl group at α-position was bulkier. Furthermore, the optical purity of asymmetric amines was determined by measuring gas chromatographic peak areas of diastereoisometic amide components.  相似文献   

4.
An immobilized chloroplast film, prepared by immobilizing spinach chloroplasts in 2 wt% agar gel, was attached to a SnO2 optically transparent electrode to obtain the immobilized chloroplast film electrode. The immobilized chloroplast film electrode worked as a photoanode under illumination in the presence of methyl viologen, which was an electron carrier from chloroplasts to the SnO2 optically transparent electrode. Water photolysis for producing hydrogen by a photoelectrochemical cell using the immobilized chloroplasts film electrode was successfully achieved. A smooth platinum electrode was used as a cathode to produce hydrogen. The pH and temperature of the anolyte were kept at 7.8 and 25°C. Optimizations of the concentrations of methyl viologen and chlorophyll in the immobilized chloroplast film were studied. The optimum thickness for the immobilized chloroplast film was about 0.8 mm. The immobilized chloroplasts had higher storage stability than that of isolated chloroplasts and they retained more than 50% of the initial activities of photosystem I and photosystem II after 10 days when they were stored at 4°C in the dark. It was conceived from the relationship between the photocurrent and the photosystem I and II activities that the main cause for the decrease in the photocurrent was the photochemical inactivation of photosystem II.  相似文献   

5.
A gas-liquid chromatographic technique was applied to the separation of pyrrolnitrin and its derivatives. The simultaneous use of a flame detector and an electron capture detector made possible the distinction between the nitro derivatives of pyrrolnitrin and the other metabolites. The metabolites could be readily quantitated with the electron capture detector, offering a much more sensitive assay than the flame detector.  相似文献   

6.
Reversed-phase chromatography has been applied to the rapid separation of E. coli 5S rRNA and has also been adapted for use on an analytical scale for the rapid (about 30 min) separation of small quantities (0.1 Ap260 unit) of l6s and 23S rRNAs. Compared to other techniques, this nondestructive method is faster, more sensitive, and gives better resolution.  相似文献   

7.
An improved method of fractionating the myoinositol esters of indoleacetic acid (IAA) from maize kernels by gas-liquid chromatography has been developed. Mass spectrometry was employed as an aid in identification of the esters. Maize kernels contain three groups of esters of IAA: (a) IAA myoinositols, (b) IAA myoinositol arabinosides, and (c) IAA myoinositol galactosides. Each group has three chromatographically distinguishable isomers. The glycosylinositols described are unique in that carbon 1 of the sugar is attached to the hydroxyl at C-5 of the myoinositol.  相似文献   

8.
Abstract

An improved procedure is described for the collection and elution of low levels of radioactive fatty acid methyl esters separated by gas-liquid chromatography. A gas chromatographic effluent splitter was employed to partition fatty acid methyl ester samples in the column effluent, Condensation of a portion of the eluted fatty acids was accomplished in borosilicate glass tubing collectors maintained at ?70°C, Quantitation of nanomolar levels of fatty acid methyl esters was accomplished by calibrating the gas chromatographic flame ionization detectors with the splitters opened or closed. The elution of condensed radioactive fatty acid methyl esters from the glass collectors was complete when benzene followed by a toluene based scintillation fluid were employed as solvents. The method described may be applicable to the analysis of cis-trans isomers of unsaturated fatty acids.  相似文献   

9.
Comparison of the cellular fatty acids of 10 strains of Mycobacterium marinum and 35 strains of Mycobacterium kansasii revealed similarities within each species but differences between these two photochromogenic mycobacteria. A branched-chain fatty acid characteristic of M. kansasii was found in trace amounts in 2 of the 10 strains of M. marinum.  相似文献   

10.
The relative responses of neomycins B and C have been determined by a microbiological agar-diffusion method, a turbidimetric method, and by a recently developed gas-liquid-chromatographic (GLC) method capable of separating the neomycin isomers. The ratios of response of neomycin C to neomycin B by the individual methods were as follows: agar-diffusion method, 1:3; turbidimetric method, 1:2.5; and GLC method, 1:1. When neomycin C is assumed to have 35% biological activity of neomycin B, the calculated drug contents of neomycin sulfate powders obtained by the GLC method correlated well with values obtained by the microbiological agar-diffusion assay method.  相似文献   

11.
A procedure is described for the chromatographic detection and isolation of DNA-RNA hybrids on columns of methylated albumin coated on kieselguhr (MAK). Its use is illustrated with both annealed and enzymatically synthesized hybrids. The method has the advantage of a wide range in capacity and resolution and permits actual isolation of the hybrid structure. It is uniquely effective in experiments involving hybridization with small DNA fragments.  相似文献   

12.
Quantitative gas-liquid chromatographic methods for the determination of 5-propargyl-2-furylmethyl dl-cis, trans-chrysanthemate, furamethrin, have been developed. The base line before the furamethrin peak of GLC drifted on the column with 2% silicone XE-60 coated on 60 ~ 80 mesh, acid-washed and DMCS-treated Chromosorb W (Method B), which suggested partial decomposition of furamethrin, however, a fine chromatogram was obtained when sodium borate was added to the column supporter (Method A). By utilizing an adequate internal standard, furamethrin was determined with the standard deviation of about 0.8% by Method B as well as Method A, the values being substantially equal to those obtained by the TLC-UV method previously reported. In addition, the trans and cis isomers in technical products of furamethrin were separated from each other on a 5% silicone DC QF-1 column and the results obtained by analyzing the mixtures indicate that the ratio can be accurately determined by their area ratio.  相似文献   

13.
The present time, chloropicrin (CP) is commonly used as the fumigant for stored grain insects, nematodes, soil fungus and weed seeds. The quantitative determination of CP has been performed by total chlorine method1), colorimetric method2), and polarography3). However, these methods require a great deal of trouble. In the previous paper, the author reported on the operating conditions and retention datas for the determination of CP by gas-liquid chromatography (GLC)4). The method reported here is an application of this work for analysis of liquid soil fumigants.  相似文献   

14.
The absolute configuration of several hydroxywarfarin isomers was assigned using a comparison of elution order on chiral stationary phases, optical rotation, and circular dichroism (CD) spectra, with confirmation of assignments made by comparison between experimental and calculated CD spectra and selective synthesis of hydroxywarfarin isomers from enantiopure warfarin using human liver microsomes. Chirality 26:95–101, 2014. © 2013 Wiley Periodicals, Inc.  相似文献   

15.
Defatted and decaseinated human milk was concentrated and was fractionated on a preparative DEAE cellulose column. Elution with various concentrations of sodium chloride in Tris-HCl buffer (pH 8.0, 0.01 M) resulted in fractions that were rich in either secretory immunoglobulin A (SIgA) (0.1 M Nad) or free secretory component (SC) (0.05 M NaCl). The fractions, which were eluted with 0.10 M NaCl from the preparative column, were further fractionated on a G-200 Sephadex column. Repeated fractionation on this column resulted in a single purified fraction, which contained very high SIgA activity and showed immunological cross-reaction with both SC and serum IgA. Additional studies indicated that this fraction was homogeneous as shown by immunoprecipitin and disc gel electrophoresis. Injection of this purified SIgA into rabbits resulted in the production of monospecific antiscil.  相似文献   

16.
17.
We have prepared a series of N-TFA-glycyl and N-TFA-l-prolyl dipeptide methyl ester from the corresponding dipeptide methyl esters by treating them with (TFA-Gly)2O and TFA-l-Pro-Cl, respectively. Separation of these tripeptide derivatives by G.L.C. was studied and a relationship between the amino acid compositions of the tripeptides and their qi-values (relative retention values) was observed, analogous to the case of the dipeptides previously reported.  相似文献   

18.
A convenient gas-liquid chromatography procedure to quantify poly-beta-hydroxybutyrate and poly-beta-hydroxyvalerate in activated sludge was developed by combining lyophilization of the samples, purification of the chloroform phase by water reextraction, and the use of capillary columns. With a flame ionization detector the sensitivity was estimated at 10 g/liter.  相似文献   

19.
The application of the phenol-duponol method to extraction of nucleic acids from HeLa cells is described. Chromatography of the phenol extract on an esterified bovine serum albumin column with a salt gradient of sodium chloride gives separation of soluble RNA, DNA, and two different high molecular RNA fractions. Ultracentrifugation of the DNA eluted from the column gives a sedimentation coefficient (s20o,w) of 38, which agrees with ultracentrifugation data on the phenol extract. The eluted RNA appears polydisperse at low ionic strength, but at high ionic strength and after alcohol precipitation two fractions with the sedimentation coefficients of 16 and 25 to 29, respectively, were obtained.  相似文献   

20.
Samples of Nile blue sulphate (Geigy and G. T. Gurr) were separated by silicic acid thin layer chromatography. The blue sulphated oxazine base was found to consist of 3 components with identical absorption spectra in the visible range. These probably represent isomeric forms of the dye. The red oxazone travelled as a single component. At least 6 minor constituents, present in small amount, were identified. Spectrophotometric examination showed that the sulphated oxazine base has 3 absorption maxima. The absorption spectrum is influenced by pH, dye concentration, dye solvent, and physical state. The absorption spectra of the oxazone and free oxazine base were also measured. These showed marked solvatochromic effects, absorption maxima moving to shorter wavelengths with decreasing solvent polarity.  相似文献   

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