Reaction efficiency of organic alkalis with various classes of lipids during thermally assisted hydrolysis and methylation |
| |
Authors: | Yasuyuki Ishida Mizuho Katagiri Hajime Ohtani |
| |
Affiliation: | 1. Department of Biological Chemistry, College of Bioscience and Biotechnology, Chubu University, Kasugai 487-8501, Japan;2. Department of Applied Chemistry, Graduate School of Engineering, Nagoya University, Nagoya 464-8603, Japan;3. Department of Materials Science and Engineering, Graduate School of Engineering, Nagoya Institute of Technology, Nagoya 466-8555, Japan |
| |
Abstract: | Reaction efficiencies of two organic alkalis, tetramethylammonium hydroxide (TMAH) and trimethylsulfonium hydroxide (TMSH), with lipids during thermally assisted hydrolysis and methylation (THM) were examined focusing on (1) the types of lipids and (2) degree of unsaturation of fatty acid moieties. Different types of lipids such as triglycerides, phospholipids, free fatty acids and cholesteryl esters containing saturated, monounsaturated or polyunsaturated fatty acid (PUFA) residues were subjected to THM-gas chromatography (GC) in the presence of TMAH or TMSH. The obtained results revealed that the THM reaction using TMAH allowed almost quantitative methylation of saturated and monounsaturated fatty acid components independently of the classes of lipids. However, strong alkalinity of TMAH brought about isomerization and/or degradation of PUFA components. In contrast, the use of TMSH was effective to highly sensitive detection of PUFA as well as saturated and monounsaturated fatty acid components contained in triglycerides, phospholipids (phosphatidylcholines) and free fatty acids. On the other hand, TMSH was proved to react hardly with any kind of fatty acid residues in cholesteryl esters due to their steric hindrance. |
| |
Keywords: | |
本文献已被 ScienceDirect 等数据库收录! |
|