Showing papers on "Thin-layer chromatography published in 1985"
TL;DR: Seven species of fresh mangrove leaves were homogenized using chloroform—methanol and the extract was diluted with water to precipitate out triterpenoids and sterols, which were separated into neutral and acidic fractions.
136 citations
TL;DR: A high-performance thin-layer chromatographic method, not involving preliminary column chromatography, for separating mixtures of nonpolar lipids, glycosphingolipidosis, and phospholipids in one dimension, and a simple and rapid fractionation procedure, using Sep-Pak silica cartridges, has been developed.
127 citations
TL;DR: The results of gas chromatography mass spectrometry revealed that hydroxy fatty acid components of the hydroxy derivatives were derived from isomeric hydroperoxides of oleic acid, linoleic Acid, arachidonic acid and docosahexanoic acid.
Abstract: A convenient method for the preparation of hydroperoxy and hydroxy derivatives of phosphatidylcholine (PC) and phosphatidylethanolamine (PE) is described. PC and PE obtained from rat liver were oxidized with singlet oxygen by using methylene blue as the photosensitizer, and their hydroperoxides were isolated with the aid of reverse phase liquid chromatography. The hydroxy derivatives were obtained by reducing the hydroperoxides with sodium borohydride. The results of gas chromatography mass spectrometry revealed that hydroxy fatty acid components of the hydroxy derivatives were derived from isomeric hydroperoxides of oleic acid, linoleic acid, arachidonic acid and docosahexanoic acid. Normal phase high performance liquid chromatography did not separate the hydroperoxy and hydroxy derivatives from the respective unoxidized phospholipids, although unoxidized PC and PE were separated from each other. However, the hydroperoxy and hydroxy derivatives could be distinguished from unoxidized phospholipid species on reversed phase thin layer chromatography.
89 citations
TL;DR: The observed levels of saponin in soya, as estimated by thin-layer and gas chromatography, are much lower than that previously reported using the former approach and reasons for this discrepancy are discussed.
57 citations
TL;DR: A new antitumor antibiotic, terpentecin was isolated from the culture broth of strain MF730-N6, and prolonged the survival period of mice bearing leukemia L-1210, P388 and Ehrlich ascites carcinoma.
Abstract: A new antitumor antibiotic, terpentecin was isolated from the culture broth of strain MF730-N6. Strain MF730-N6, isolated from soil, was found to belong to the genus Kitasatosporia. The antibiotic was extracted with chloroform, purified by column chromatography using silica gel and Diaion HP-20 successively, and finally purified by high performance reverse-phase thin layer chromatography. The molecular formula of terpentecin was determined to be C20H28O6 (molecular weight, 364). The antibiotic inhibited the growth of Gram-positive and Gram-negative bacteria, and prolonged the survival period of mice bearing leukemia L-1210, P388 and Ehrlich ascites carcinoma.
55 citations
TL;DR: In this paper, conditions for the separation of (1→2)-, ( 1→3)-, 1→4)- and 1→6)-linked homogeneous d -gluco-oligosaccharides and polysaccharides were investigated by high-performance liquid chromatography on a 3-μm chemically modified amine column (ERC-NH-1171) and by thin-layer chromatography (TLC) on three kinds of silica gel plates.
54 citations
TL;DR: Revue de 174 references sur l'analyse des isocyanates organiques atmospheriques par colorimetrie, spectrometrie IR, chromatographie en phase gazeuse, sur couche mince, HPLC.
Abstract: Revue de 174 references sur l'analyse des isocyanates organiques atmospheriques par colorimetrie, spectrometrie IR, chromatographie en phase gazeuse, sur couche mince, HPLC
52 citations
TL;DR: A previously suggested close relationship between M. leprae and M. gordonae was not supported because of the homogeneity of the chain lengths of the mycolic acids in each species.
Abstract: The mycolic and fatty acids of three samples each of Mycobacterium leprae and Mycobacterium gordonae were compared. Acids released by whole-organism alkaline hydrolysis were converted to 4-nitrobenzyl esters and mycolic acids were further derivatized to t-butyldimethylsilyl ethers. Thin-layer chromatography of the derivatized long-chain extracts showed that all three M. leprae preparations contained so-called alpha-mycolates and ketomycolates but that the M. gordonae samples had a methoxymycolate in addition to the above types. Silica gel normal-phase high-performance liquid chromatography of the total mycolic acid derivatives confirmed the lack of detectable amounts of methoxymycolates in M. leprae and reverse-phase chromatography of the individual mycolate types demonstrated the homogeneity of the chain lengths of the mycolic acids in each species. Non-hydroxylated fatty acid 4-nitrobenzyl esters were transformed to methyl esters and examined by gas chromatography. Tuberculostearic (10-methyloctadecanoic) acid was a major component of the lipids of all three M. leprae preparations but it was absent in one M. gordonae strain and a very minor component in the other representatives of this latter species. On the basis of fatty and mycolic acid compositions, therefore, a previously suggested close relationship between M. leprae and M. gordonae was not supported.
39 citations
36 citations
34 citations
TL;DR: A simple and effective procedure has been developed for eliminating silica gel from gangliosides after preparative thin-layer chromatography with yields of 92% and 90% in terms of dry weight and sialic acid content.
TL;DR: In this article, soybean seeds were extracted with chloroform-methanol (2:1), methylene chloride-mETHanol (MCL) and hexane-isopropanol (3:2) mixtures, and the seed lipids were then fractionated by column chromatography.
Abstract: Soybean seeds were extracted with chloroform-methanol (2:1), methylene chloride-methanol (2:1) and hexane-isopropanol (3:2) mixtures The seed lipids were then fractionated by column chromatography Neutral lipids were further separated by thin layer chromatography (TLC) and quantified by acid charring method Fatty acid methyl esters were prepared and analyzed by gas liquid chromatography (GLC) Our results show that methylene chloride-methanol (2:1) was as good as chloroform-methanol (2:1) for the extraction of soybean lipids, but hexane-isopropanol (3:2) was somewhat inferior
TL;DR: In this article, the results of a comparison between 5,8,4'-trihydroxy-6,7,3'-trimethoxyflavone, 5,6,8-3',4'-pentahydroxy-7methoxyFLavone and 5.6, 8, 4'-tetrahydrox-7, 3'-dimethoxy-7.3'-dimethyl-flavonoids are presented for the first time.
TL;DR: In this paper, two fractions with prostaglandin E-like activity were isolated from onion (Allium cepa) by using XAD-2 adsorption, silicic acid column chromatography and thin layer chromatography.
TL;DR: Results from a study of a reaction of oxidized ribonucleotides with a primary amine are used in the interpretation of differing results when oxidized nucleotides have been used as affinity labels for different proteins.
TL;DR: In this paper, the lipophilicity of 28 modified crown ether derivatives was determined by reversed-phase thin-layer chromatography (RPTLC) using various organic phases and supports, however the quality of the organic phase (methanol, acetone, acetonitrile) and the support characteristics influenced to a small extent the determination.
Abstract: The lipophilicity of 28 modified crown ether derivatives was determined by reversed-phase thin-layer chromatography (RPTLC) using various organic phases and supports. The lipophilicity values determined in different RPTLC systems showed good correlations, however the quality of the organic phase (methanol, acetone, acetonitrile) and the support characteristics influenced to a small extent the determination.
TL;DR: This technique may be used to determine the structural specificity of other carbohydrate-binding proteins such as lectins, toxins, and hormones or of bacteria and viruses that bind to cell surface glycoproteins as well as to identify and characterize antibody-binding oligosaccharides liberated from glycoconjugates.
TL;DR: In this paper, the importance of varying S-9 concentration in the S 9 mix is discussed to determine the presence or absence of synergical/antagonistic effect of chemical constituents of complex mixtures like the XAD extract.
TL;DR: The method was applied to the determination of the sugar composition of the glycosphingolipid globotetraosyl ceramide and the human milk oligosaccharide lacto-N-fucopentaose I.
TL;DR: The low molecular weight iron found in the guinea pig reticulocyte has been partially characterized and preparation under nitrogen improves recovery of low molecularWeight iron, suggesting that the iron is in the ferrous oxidation state.
Abstract: The low molecular weight iron found in the guinea pig reticulocyte has been partially characterized. On thin layer chromatography it is distinguishable from the iron complexes of a variety of nucleotides, sugars, and amino acids. On paper chromatography it comigrates with a 250-nm absorbing, orcinol-positive material. The eluted count peak contains phosphorus. Approximately 1 microgram of iron is recovered from 1 ml of hemolyzed red cells. Preparation under nitrogen improves recovery of low molecular weight iron, suggesting that the iron is in the ferrous oxidation state.
TL;DR: After trichloroacetic acid extraction of the walls of alkalophilic Bacillus sp.
Abstract: SUMMARY: After trichloroacetic acid extraction of the walls of alkalophilic Bacillus sp. strain C-125 grown at an alkaline or a neutral pH, two acidic structural polymer fractions were isolated by ionexchange chromatography and gel chromatography. One was a teichuronic acid fraction containing N-acetyl-d-fucosamine, glucuronic acid and galacturonic acid in a molar ratio of 1: 1: 1. This teichuronic acid amounted to 390 μg per mg peptidoglycan in the walls of the bacterium grown at an alkaline pH or 80 μg per mg at a neutral pH. The molecular weight of the teichuronic acid from the cells grown at an alkaline pH was 70000 compared to a molecular weight of 48000 at a neutral pH as estimated by gel chromatography. The other fraction contained glucuronic acid and l-glutamic acid in a molar ratio of 1: 5. This fraction was either a copolymer of both the acids or a mixture of polyglucuronate and polyglutamate. This fraction amounted to 560 μg per mg peptidoglycan in the walls of the bacterium grown at an alkaline pH or 240 μg per mg at a neutral pH. The molecular weight of the fraction from both the wall preparations was about 19000.
TL;DR: A remarkable purification of active compounds was achieved without serious losses of activity, thus enabling further purification and mass spectrometric studies of the main mutagens.
TL;DR: A thin-layer chromatographic method facilitated analysis of the activity of cellulolytic enzymes and separation of cellooligosaccharides on silica gel plates with high resolution.
TL;DR: The chemical methylation of phosphatidylethanolamine by S-adenosyl methionine (SAM) is most active when carried out at alkaline pH's and thin layer chromatography indicates the formation of the expected products.
TL;DR: In this paper, the authors applied the concept of Hildebrand's solubility parameter to the discussion of the mobility of each compound, on the solvents used as the developer.
Abstract: The metal complexes ofmeso-tetrakis (p-tolyl) porphine (TTP) are chromatographed on octadecyl-bonded silica gel thin-layer with various organic solvents of relatively high polarity used as the eluent. The mobility of the metal-TTP complex depends on its centralmetal, increasing in the order of Cu(II)
TL;DR: In this paper, an equilibrium sandwich chamber for continuous thin-layer chromatography was used to study overloaded systems of the heptane + methylene chloride-silica type, and the effect of sample concentration and volume on the maximum separation yield was investigated.
Abstract: An equilibrium sandwich chamber for continuous thinlayer chromatography was used to study overloaded systems of the heptane + methylene chloride-silica type. Mixtures of two or three dyes were used as the model samples. Wide starting zones were formed using a glass distributor (frontal chromatography stage), then the movement of the zones was recorded during continuous elution. The effect of sample concentration and volume on the maximum separation yield was investigated. Band compression effects are illustrated for samples dissolved in solvents having a low eluent strength. Satisfactory analogy was found to separations in preparative column chromatography. Good separation yield was obtained for frontal + elution TLC: depending on the differences in the RF values of the components, 6–16 mg samples were completely separated on 0.5×100×75 mm layers containing ca. 1 g of silica.
Book•
01 Jan 1985
TL;DR: Partial table of contents: Lasers and Thin Layer Chromatography: Present and Future (M. Bicking, M. Armstrong and G. Stine).
Abstract: Partial table of contents: Lasers and Thin Layer Chromatography: Present and Future (M. Bicking) Bonded Stationary Phases for Reversed-Phase Thin Layer Chromatography (R. Scott) Rotating-Disk Thin Layer Chromatography (D. Zink) Time-Optimized Thin Layer Chromatography in a Chamber with Fixed Plate Lengths (R. Tecklenburg, et al.) Quantitativeness of Scanning Densitometry (D. Rogers) Discovery of New Compounds by Thin Layer Chromatography (S. Ahuja) New Methods in Analyzing Radiochromatograms and Electropherograms (H. Filthuth) Lipids of Human Milk (J. Bitman et al.) Direct Determination of Plasmalogens on Thin Layers (S. Levin et al.) Separation and Quantitation of Anionic, Cationic, and Nonionic Surfactants by Thin Layer Chromatography (D. Armstrong and G. Stine).