Thin-layer chromatography

About: Thin-layer chromatography is a research topic. Over the lifetime, 7494 publications have been published within this topic receiving 124179 citations. The topic is also known as: TLC.

Preparation of hydroperoxy and hydroxy derivatives of rat liver phosphatidylcholine and phosphatidylethanolamine.

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.

Purification and characterization of tannase from Paecilomyces variotii: hydrolysis of tannic acid using immobilized tannase.

Abstract: An extracellular tannase (tannin acyl hydrolase) was isolated from Paecilomyces variotii and purified from cell-free culture filtrate using ammonium sulfate precipitation followed by ion exchange and gel filtration chromatography. Fractional precipitation of the culture filtrate with ammonium sulfate yielded 78.7% with 13.6-folds purification, and diethylaminoethyl–cellulose column chromatography and gel filtration showed 19.4-folds and 30.5-folds purifications, respectively. Molecular mass of tannase was found 149.8 kDa through native polyacrylamide gel electrophoresis (PAGE) analysis. Sodium dodecyl sulphate–PAGE revealed that the purified tannase was a monomeric enzyme with a molecular mass of 45 kDa. Temperature of 30 to 50°C and pH of 5.0 to 7.0 were optimum for tannase activity and stability. Tannase immobilized on alginate beads could hydrolyze tannic acid even after extensive reuse and retained about 85% of the initial activity. Thin layer chromatography, high performance liquid chromatography, and 1H-nuclear magnetic resonance spectral analysis confirmed that gallic acid was formed as a byproduct during hydrolysis of tannic acid.

Isolation and Identification of Dipeptidyl Peptidase IV-Inhibitory Peptides from Trypsin/Chymotrypsin-Treated Goat Milk Casein Hydrolysates by 2D-TLC and LC-MS/MS.

Abstract: New dipeptidyl peptidase IV (DPP-IV)-inhibitory peptides from trypsin/chymotrypsin-treated goat milk casein hydrolysates were isolated and identified by two-dimensional silica thin-layer chromatography (2D-TLC) combined to nano LC-MS/MS 2D-TLC with chloroform/methanol/25% ammonia (2:2:1) and n-butanol/acetic acid/water (4:1:1) as the first- and second-dimension eluents, respectively, in analytical and semipreparative scales, was set up and verified by reversed-phase high-performance liquid chromatography (RP-HPLC) to be feasible and efficient to separate the hydrolysates Five new DPP-IV-inhibitory peptides, four relatively large oligopeptides (MHQPPQPL, SPTVMFPPQSVL, VMFPPQSVL, and INNQFLPYPY), and AWPQYL were identified, and INNQFLPYPY showed a notable IC50 value of 4008 μM as an uncompetitive inhibitor Interactive effects on DPP-IV inhibition were also observed among separated fractions and pure synthetic peptide mixtures with concentration-dependent activity The study gives new insights into goat casein hydrolysates with identified DPP-IV-inhibitory peptides efficiently isolated by 2D-TLC, which provides a simple and cost-efficient separation process and is compatible with liquid chromatography-tandem mass spectrometry (LC-MS/MS) identification