Details of a Researcher - Soga, Tomoyoshi

Papers - Soga, Tomoyoshi

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Simultaneous determination of inorganic anions, organic acids, amino acids and carbohydrates by capillary electrophoresis

Soga, T., Ross, G.A.

J. Chromatogr. A 837 ( 1-2 ) 231 - 239 1999.04

Research paper (scientific journal), Joint Work, Accepted

A capillary zone electrophoretic method for the simultaneous analysis of inorganic anions, organic acids, amino acids and carbohydrates was developed with indirect UV detection using 2,6-pyridine dicarboxylic acid as the background electrolyte. This is the first paper to report their simultaneous analysis. Highly alkaline conditions were used in order to confer a negative charge not only on inorganic and organic anions but also on amino acids and carbohydrates, and to promote their migration towards the anode. Electroosmotic flow was reversed in the direction of the anode by adding cetyltrimethylammonium hydroxide to the electrolyte. Outstanding separations were obtained and electrophoretic mobilities of 82 compounds including nine inorganic anions, 23 organic acids, 18 amino acids and 32 carbohydrates were determined by the method. Under the optimized conditions 43 compounds were well separated in a single run. The relative standard deviations (n=5) of the method were better than 0.5% for migration times and between 0.8% and 4.9% for peak areas except for a few compounds. The detection limits for anions and amino acids were in the range from 6 to 12 mg/l and for carbohydrates from 23 to 35 mg/l with 300 mbar·s pressure injection (6 nl) at a signal-to-noise ratio of three. This method could be readily applied to the simultaneous determination of inorganic anions, organic acids, amino acids and carbohydrates in soy sauce, nutrient tonic and pineapple.

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Simultaneous determination of inorganic anions, organic acids and metal cations by capillary electrophoresis

Soga, T., Ross, G.A.

J. Chromatogr. A 834 ( 1-2 ) 65 - 71 1999.02

Research paper (scientific journal), Joint Work, Accepted

A capillary electrophoresis method for the simultaneous analysis of inorganic anions, organic acids and metal cations was developed. 2,6-Pyridinedicarboxylic acid (PDC) was used as the background electrolyte to permit indirect UV detection of anions. The PDC also worked to confer a negative charge on metal cations via PDC-complex formation. In order to detect both anions and metal–PDC complexes simultaneously, the electroosmotic flow was reversed by adding cetyltrimethylammonium hydroxide. In the method detection of anions was carried out with indirect UV detection, whereas metal cations were detected directly. Thirteen anions and three metal cations were completely separated at the operating buffer, pH 5.7. The R.S.D. (n=6) values of the method were better than 0.2% for migration time and between 1.1% and 3.9% for peak area. Calibration graphs were linear with correlation coefficients better than 0.9992. The minimum detectable levels ranged from 0.2 mg l−1 to 1.9 mg l−1 with 300 mbar pressure injection (6 nl) at a signal-to-noise ratio of 3. This method is simple, rapid and reproducible and could be readily applied to the simultaneous determination of anions and metal cations in a plating bath sample.

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Simultaneous Determination of Monosaccharides in Glycoproteins by Capillary Electrophoresis

Soga, T., Heiger, D.N.

Anal. Biochem. 261 ( 1 ) 73 - 78 1998.07

Research paper (scientific journal), Joint Work, Accepted

A rapid, easy, and reproducible capillary electrophoretic method for the simultaneous determination of acidic, neutral, and amino sugars and sugar alcohols was developed. Underivatized mannuronic acid, glucuronic acid, galacturonic acid, N-glycolylneuraminic acid, N-acetylneuraminic acid, glucosamine, galactosamine, mannose, xylose, glucose, galactose, fucose, ribose, mannitol, sorbitol, xylitol, and inositol were simultaneously determined with indirect UV detection using 2,6-pyridinedicarboxylic acid as a background electrolyte. A highly alkaline pH condition was used in order to charge carbohydrates negatively and to promote migration toward the anode. Electroosmotic flow was reversed to the direction of the anode by adding cetyltrimethylammonium bromide to the electrolyte. The separation of the carbohydrates was investigated by optimizing the operating pH value and satisfactory resolution was obtained at pH 12.1. The relative standard deviations of the method for carbohydrates were between 0.02 and 0.33% for migration times and were greater than 2.7% for peak areas (n = 6). The minimum detectable level ranged from 23 to 71 microM with a 6-nl injection at a signal-to-noise ratio of 3. This method was applied to the composition analysis of monosaccharides in glycoprotein. After acid hydrolysis of fetuin under each optimum condition, sialo, neutral, and amino sugars were quantified under the same electrophoretic condition.

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Kapillarelektrophorese-eine Prädestinierte Technik für die Analyse von Kationen und Anionen in Elektrolyten für die Galvanische und Chemische Metallisierung

Jegle, U., Serwe, M., Soga, T.

Galvanotechnik 89 1478 - 1485 1998

Research paper (scientific journal), Joint Work, Accepted

Capillary electrophoretic determination of inorganic and organic anions using 2,6-pyridinedicarboxylic acid: effect of electrolyte's complexing ability

Soga, T., Ross, G.A.

J. Chromatogr. A 767 ( 1-2 ) 223 - 230 1997.04

Research paper (scientific journal), Joint Work, Accepted

A capillary zone electrophoresis method was developed with indirect UV detection for the analysis of inorganic and organic anions using a background electrolyte (BGE), 2,6-pyridinedicarboxylic acid (PDC). The parameters which influence the separation of these anions, such as electrolyte pH, concentration of PDC and applied voltage, were investigated. Three inorganic anions and nine organic acids were determined simulataneously in less than 7 min. The R.S.D. (n66) values of the method were around 0.1% for migration time and better than 2.6% for peak area. This method is rapid, sensitive and quantitative and could be readily applied to analysis of inorganic and organic anions in beer. In the present paper, the effect of the complexing ability of the BGE on the analysis of organic acids is also discussed.

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Determination of Inorganic and Organic Anions in Beer and Wort by Capillary Electrophoresis

Soga, T., Wakaura, M

J. Am. Soc. Brew. Chem 55 ( 2 ) 44 - 46 1997.04

Research paper (scientific journal), Joint Work, Accepted

A rapid, easy, and reproducible method for the determination of inorganic and organic anions in beer and wort by capillary electrophoresis was developed. Three inorganic anions (chloride, sulfate, and phosphate) and nine organic acids (oxalate, formate, malate, citrate, succinate, pyruvate, acetate, lactate, and pyroglutamate) were separated and quantified in less than 7 min. Sample preparation was simple and consisted only of degassing the beer by sonication and 1:5 dilution with Milli Q water prior to injection. Satisfactory reproducibility was obtained, and the concentrations of anions were in good agreement with those found by conventional techniques.

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Poly(vinyl alcohol)-Coated Capillaries – A Solution for Many Application Areas in Capillary Electrophoresis

Jegle, U., Grimm, R., Godel, H., Schuster, R., Ross, G. A., Soga, T.

LC GC International 10 ( 3 ) 176 - 188 1997.03

Research paper (scientific journal), Joint Work, Accepted

Analysis of halides, oxyhalides and metal oxoacids by capillary electrophoresis with suppressed electroosmotic flow

Soga, T., Inoue, Y., Ross, G.A.

J. Chromatogr. A 718 ( 2 ) 421 - 428 1995.12

Research paper (scientific journal), Joint Work, Accepted

A rapid and easy method for the determination of halides, oxyhalides and metal oxoacids by capillary electrophoresis was developed. This is the first paper to report their simultaneous analysis. Electroosmotic flow was suppressed more than 40-fold by using a poly(ethyleneglycol)-coated capillary, compared with that in a bare fused-silica capillary under similar conditions. Using this capillary, the separation of eleven anions was accomplished. Anion migration was dependent only on their mobility and detection was carried out directly with a diode-array detector. The R.S.D.s were better than 0.6% for migration time and between 1.0% and 3.4% for peak area. Calibration graphs for all the anions were linear, with correlation coefficients better than 0.9995. Using stacking sample preconcentration, the achievable lower detection limits were found to be in the range 14–260 μg 1−1. This represents a 33–43-fold increase in sensitivity over the results obtained by using 200 mbar·s pressure injection.

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Determination of catecholamines in urine and plasma by on-line sample pretreatment using an internal surface boronic acid gel

Soga, T., Inoue, Y.

J. Chromatogr. Biomed. 620 ( 2 ) 175 - 181 1993.10

Research paper (scientific journal), Joint Work, Accepted

An automated method of analysis of catecholamines using a new packing material, internal surface boronic acid gel, was developed. The new support is designed with a carboxymethylcellulose-bonded external surface in order to be non-adsorptive to proteins and with a phenylboronic acid-bonded internal surface to retain only catecholamines. This packing support displayed an affinity for basic or neutral catecholic compounds with no protein adsorption and enabled on-line sample pretreatment of catecholamines in urine and deproteinized plasma. The catecholamines were selectively adsorbed on the new material and separated on a reversed-phase or a cation-exchange column. These compounds were then detected electrochemically. The limits of quantitation were 1.5–3.0 ng/ml in urine and 10–15 pg/ml in plasma, at a signal-to-noise ratio of 5.

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Determination of carbohydrates by hydrophilic interaction chromatography with pulsed amperometric detection using postcolumn pH adjustment

Soga, T., Inoue, Y., Yamaguchi, K.

J. Chromatogr. 625 ( 2 ) 151 - 155 1992.11

Research paper (scientific journal), Joint Work, Accepted

An HPLC method for the determination of carbohydrates using a postcolumn pH adjustment technique with lithium hydroxide solution followed by pulsed amperometric detection was developed. In conjunction with hydrophilic interaction chromatography, the technique was used to determine reducing sugars, non-reducing sugars and sugar alcohols. Detection limits from 0.7 to 2.7 ng with a signal-to-noise ratio of 3 were achieved. The relative standard deviation for peak was better than 2.7%. The postcolumn pH adjustment technique enabled gradient elution to be used.

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Comprehensive Measurement and Comparison of Ionic Small Molecules Contained in Citrus Unshiu Marc. Using Metabolomic Analysis

Hara, Y., Sugawara, A., Yamada, KC, Endo, K., Ashitani, S., Igarashi, K., Soga, T., Shinjo, A., Kuroda, H.

JOURNAL OF THE JAPANESE SOCIETY FOR FOOD SCIENCE AND TECHNOLOGY (THE JAPANESE SOCIETY FOR FOOD SCIENCE AND TECHNOLOGY) 67 ( 12 ) 499 - 513 2020.12

Research paper (scientific journal), Joint Work, Accepted

Trigonelline Attenuates Lipopolysaccharide-Induced Nitric Oxide Production and Downregulates Inflammation Associated Gene Expressions

Aizawa, Y., Suzuki, T., Saito, A., Satoh, K., Ogura, T., Wakayama, M., Soga, T., Tsuji, Y., Honmma, K., Inoue, H.

Food preserv. Sci. 46 ( 6 ) 275 - 280 2020.11

Research paper (scientific journal), Joint Work, Accepted

Trigonelline, an N-methylnicotinic acid, is found in fenugreek (Trigonella foenum-graecum L.) and coffee beans. Trigonelline has been reported to prevent cardiovascular and Alzheimer’s diseases.However, the potential pharmacological application of trigonelline in in fl ammatory responses is poorly understood, particularly in macrophages. In the present study, we investigated the effects and underlying molecular mechanisms of trigonelline on 100 ng /mL lipopolysaccharide (LPS) -induced inflammatory responses in RAW 264.7 mouse macrophages. 50 uM Trigonelline elicited a marked reduction in LPS - mediated production of nitric oxide (NO) compared with LPS - treated cells. Subsequently, the mRNA expression levels of inducible nitric oxide (iNOS), cyclooxygenase-2 (COX2),and pro-inflammatory cytokines, including tumor necrosis factor a (TNF-a), interleukin (IL) -6, and IL-1beta in LPS-treated cells were significantly decreased by trigonelline co-treatment. Furthermore, we found that treatment of cells with LPS elevated the gene expression of reactive oxidative species (ROS)-associated molecules, such as p47phox and p67phox, whereas trigonelline treatment significantly decreased them. Our data suggested that trigonelline inhibited inflammation and oxidative stress, resulting in the potential application of this compound in the prevention of inflammatory diseases.

Establishment of Basic Lipidomics Platforms for Discovery of Lipid Biomarkers

Ikeda, K., Taguchi, R., Soga, T.

Bunseki Kagaku (The Japan Society for Analytical Chemistry) 61 ( 6 ) 501 - 512 2012.06

Research paper (scientific journal), Joint Work

Lipidomics is one of the major approaches in metabolomics, and often uses a liquid chromatography-mass spectrometer (LC-MS) to obtain profiling of lipid metabolites and to detect changing molecules statistically. However, previously reported methods have been technically insufficient in the simultaneous analysis of amphiphilic glycosphingolipids, such as gangliosides, and in the global detection of various polar metabolites from complex lipid mixtures. Here, we report on newly targeted and non-targeted methods to measure these lipid metabolites sensitively. In the targeted approach, we were able to detect individual ganglioside molecular species using the combination of reversed-phase or hydrophilic interaction liquid chromatography and ESI-MS with multiple reaction monitoring (MRM).
Meanwhile, in a non-targeted approach, global analysis of various polar metabolites was possible by reverse-phased high-resolution (LC) coupled quadrapole time-of-flight MS and sensitive twodimensional (2D) profiling. Our methods will be useful for the elucidation of cancers, metabolic syndrome and nervous-system diseases, etc. ; these diagnostic markers may be detectable.

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Metabolome Analysis of Colon Tumor Tissues by Capillary Electrophoresis Time-of-Flight Mass Spectrometer

Hirayama, A., Kami, K., Sugimoto, M., Tomita, M., Soga, T.

J. Mass Spectrom. Soc. Jpn. 57 ( 3 ) 183 - 186 2009.06

Research paper (scientific journal), Joint Work

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CE-MSによるメタボローム解析

Soga, T.

生物物理化学 52 ( 3 ) 91 - 94 2008.09

Research paper (scientific journal), Single Work

Metabolomics, which can be defined as the measurement of the level of all intracellular metabolites, has become a powerful new tool for gaining insight into cellular and physiological responses. Here we have developed a comprehensive and quantitative analysis method based on capillary electrophoresis mass spectrometry (CE-MS). In this marriage of techniques, CE confers rapid analysis and efficient resolution, and MS provides excellent selectivity and sensitivity. Previous work in our laboratory demonstrated that CE-MS techniques were quite useful for the metabolome analysis. We applied this approach to profile liver metabolites following acetaminophen-induced hepatotoxicity and revealed ophthalmate as a sensitive indicator of reduced glutathione (GSH) depletion. Our results specifically indicate that serum ophthalmate is a sensitive indicator of hepatic GSH depletion, and may be a new biomarker for oxidative stress.

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Development of CE-MS for Meabolomics.

Soga, T.

J Mass Spectrom Soc Jpn 51 ( 3 ) 407 - 411 2003.06

Research paper (scientific journal), Single Work, ISSN 1340-8097

Metabolomics, which can be defined as the measurement of the level of all intracellular metabolites, has become a powerful new tool for gaining insight into functional biology. Intercellular metabolites not only provide metabolic phenotypes but also inducers to gene expression. Thus, metabolome analysis will be as important as genome and proteome research. However, very few methods for a large-scale metabolite analysis have been reported. This paper reports a method for the direct and quantitative analysis of charged metabolite using capillary electrophoresis electrospray ionization mass spectrometry (CE-ESI-MS). Its utility is demonstrated in the determination of basal metabolic intermediates of glycolysis and the TCA cycle pathways in Bacillus subtilis cells, yielding new information about how changes in metabolites are related to sporulation events.

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Simultaneous Determination of 8 Kinds of Organic Acids in Formula Feed by Capillary Electrophoresis.

Ishikuro, E., Hibino, H., Soga, T., Yanai, H., Sawada, H.

食品衛生学雑誌 41 ( 4 ) 261 - 267 2000.08

Research paper (scientific journal), Joint Work, ISSN 0015-6426

配合飼料中の8種類の有機酸 (ギ酸, フマル酸, 酒石酸, リンゴ酸, クエン酸, 酢酸, 乳酸及びプロピオン酸) のキャピラリー電気泳動 (CE) による分析法を開発した. 各有機酸は水で同時抽出し, ろ過した後, ろ液を0.02mol/Lの水酸化ナトリウムで希釈し, 限外ろ過フィルターユニット (分画分子量30,000) で除タンパクを行いCEに供した. 3種類の配合飼料に8種類の有機酸を0.05～2.0%の範囲で添加して回収試験を行ったところ, 平均回収率は85.1～107.3%で繰り返し精度 (RSDr) は13.6%以内であった. また, 3試験室において共同試験を行った結果, 平均回収率は87.3～105.0%, 室間再現精度 (RSDR) は16.3%以内であった.

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