Publications by authors named "Toru Nezu"

An indirect enzymatic analysis method for the quantification of fatty acid esters of 2-/3-monochloro-1,2-propanediol (2/3-MCPD) and glycidol was developed, using the deuterated internal standard of each free-form component. A statistical method for calibration and quantification of 2-MCPD-d, which is difficult to obtain, is substituted by 3-MCPD-d used for calculation of 3-MCPD. Using data from a previous collaborative study, the current method for the determination of 2-MCPD content using 2-MCPD-d was compared to three alternative new methods using 3-MCPD-d.

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A collaborative study was conducted to evaluate an indirect enzymatic method for the analysis of fatty acid esters of 3-monochloro-1,2-propanediol (3-MCPD), 2-monochloro-1,3-propanediol (2-MCPD), and glycidol (Gly) in edible oils and fats. The method is characterized by the use of Candida rugosa lipase, which hydrolyzes the esters at room temperature in 30 min. Hydrolysis and bromination steps convert esters of 3-MCPD, 2-MCPD, and glycidol to free 3-MCPD, 2-MCPD, and 3-monobromo-1,2-propanediol, respectively, which are then derivatized with phenylboronic acid, and analyzed by gas chromatography-mass spectrometry.

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We developed a novel, indirect enzymatic method for the analysis of fatty acid esters of 3-monochloro-1,2-propanediol (3-MCPD), 2-monochloro-1,3-propanediol (2-MCPD), and glycidol (Gly) in edible oils and fats. Using this method, the ester analytes were rapidly cleavaged by Candida rugosa lipase at room temperature for 0.5 h.

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An increase in serum plasmalogens (1-O-alk-1-enyl-2-acyl glycerophospholipids), which are endogenous anti-oxidative phospholipids, can potentially prevent age-related diseases such as atherosclerosis and metabolic syndrome (MetS). Very long chain fatty acids (VLCFAs) in plasma may supply the materials for plasmalogen biosynthesis through peroxisomal beta-oxidation. On the other hand, elevated levels of saturated and monounsaturated VLCFAs in plasma appear to be associated with decreased peroxisomal function, and are a symptom of age-related diseases.

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Serum plasmalogens (Pls) (1-O-alk-1'-enyl-2-acyl glycerophospholipids) are of particular interest for studies on metabolic disorders associated with oxidative stress and chronic inflammation. Serum levels of Pls are known to correlate positively with HDL-cholesterol (HDL-C); however, few studies have examined serum Pls molecular species in association with pathophysiological conditions and their clinical significance. To clarify these, we determined serum levels of individual ether glycerophospholipids in Japanese asymptomatic cohorts (n = 428; 362 male and 66 female subjects) by LC/MS/MS, and examined their correlations with clinical parameters.

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Background: Serum plasmalogens (Pls) have gained interest in several clinical symptoms such as metabolic syndrome/atherosclerosis or Alzheimer's disease possibly because of their antioxidant properties. We have developed a highly sensitive and simple method to determine plasmenylcholine (PlsCho; choline plasmalogen) and plasmenylethanolamine (PlsEtn; ethanolamine plasmalogen) separately, using a radioactive iodine and high-performance liquid chromatography ((125)I-HPLC method). The present study reports the improvement and validation of (125)I-HPLC method by introducing a quantitative standard (QS) and online detection with a flow γ-counter.

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Background: Plasmalogen is a subclass of phospholipids widely distributed in animal tissues and ingested as food; however, the absorptive characteristics of different classes of plasmalogen have not been clarified.

Aim Of Study: Our object was to compare the lymphatic output of choline and ethanolamine plasmalogens after an administration of phospholipid preparations containing each class of plasmalogens, and to analyze molecular species of plasmalogen absorbed into the lymph.

Methods: A duodenal infusion of 1 ml of 10% emulsion of choline phospholipid (PC) containing 50.

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