University of North Florida
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Stuart Chalk, Ph.D.
Department of Chemistry
University of North Florida
Phone: 1-904-620-1938
Fax: 1-904-620-3535
Email: schalk@unf.edu
Website: @unf

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Agricultural and Biological Chemistry

  • Publisher:
  • FAD Code: AGBC
  • CODEN: ABCHA6
  • ISSN: 0002-1369
  • Abbreviation: Agric. Biol. Chem.
  • DOI Prefix: 10.1271/bbb
  • Other Name(s): Bioscience, Biotechnology, and Biochemistry
  • Language: Japanese
  • Comments: Replaced by Bioscience, Biotechnology, and Biochemistry in 1991 ISSN:0916-8451 Abstracts available from 1997 v61

Citations 11

"Immobilized Catalyst For Detecting Chemiluminescence In Lipid Hydroperoxide"
Agric. Biol. Chem. 1991 Volume 55, Issue 5 Pages 1217-1223
Akira WADANO, Teturo IKEDA, Motonobu MATUMOTO and Michio HIMENO

Abstract: A study was conducted to determine whether catalysts could be immobilized on a gel for HPLC without losing their activity. Microperoxidase and cytochrome c were immobilized on Affi-prep 10, Epoxy-Toyopearl, Formyl-Toyopearl and Tresyl-Toyopearl. Chemiluminescence was detected with a Wako Pure Chemical Industries instrument. A stainless-steel column (10 cm x 4 mm) was packed with the immobilized enzyme and used with methanol - CHCl3 (9:1) as the carrier stream in a flow injection system. The reagent solution contained 1 µg mL-1 of isoluminol or luminol in 50 mM borate buffer. The specificity of each immobilized catalyst was compared with that of the free form.
Hydroperoxides, lipid Chemiluminescence HPLC Catalysis Immobilized enzyme Column

"Determination Of Glycerol In Wine By Amperometric Flow Injection Analysis With An Immobilized Glycerol Dehydrogenase Reactor"
Agric. Biol. Chem. 1991 Volume 55, Issue 4 Pages 1055-1059
Kiyoshi MATSUMOTO, Hiroaki MATSUBARA, Masashi HAMADA, Toyohiko DOI and Yutaka OSAJIMA

Abstract: A glycerol sensor was fabricated by immobilizing glycerol dehydrogenase on Amino-Cellulofine (details given). The sensor was applied in the cited determination with use of 10 mM NAD as co-enzyme, a flow rate of 1.1 mL min-1 and amperometric detection at +0.75 V vs. Ag - AgCl. The coefficient of variation (n = 10) was 0.5% and the response was stable for 26 days after reaching a maximum. Results compared favourably with those obtained by the F-kit method (Boehringer Mannheim GmBH).
Glycerol Wine White Amperometry Immobilized enzyme Reactor

"Co-immobilization Of Alcohol Dehydrogenase, Diaphorase And NAD+ And Its Application To Flow Injection Analytical System For Ethanol"
Agric. Biol. Chem. 1989 Volume 53, Issue 11 Pages 2909-2915
Hiroyuki UKEDA, Masatomo IMABAYASHI, Kiyoshi MATSUMOTO and Yutaka OSAJIMA

Abstract: Sepharose activated with CNBr was repeatedly modified with hexamethylenediamine and glutaraldehyde as spacers before use for immobilization of the cited enzymes and NAD+ at 20°C during 7 h from 0.05 M phosphate buffer of pH 8.0 (buffer A). A column of the product was used in a flow injection system for the determination of ethanol, the O consumption being measured amperometrically with a Clark O electrode maintained at -0.8 V in a flow-through cell; buffer A was used as carrier. Response was rectilinearly related to ethanol concentration. from 20 to 80 mM. The response fell markedly during the first three injections of 20 mM ethanol, but then decreased more slowly; the response after 19 injections was 70% of that after the third.
Ethanol Amperometry Electrode Buffer Column Immobilized enzyme

"Determination Of Sulfite In White Wine By Amperometric Flow Injection Analysis With An Immobilized Sulfite Oxidase Reactor"
Agric. Biol. Chem. 1989 Volume 53, Issue 9 Pages 2347-2353
Kiyoshi MATSUMOTO, Hiroaki MATSUBARA, Hiroyuki UKEDA and Yutaka OSAJIMA

Abstract: Sample (4 ml) is mixed with 2.5% gelatin solution (1 ml) to remove interfering substances (e.g., polyphenols), filtered, and diluted ~20-fold with 0.1 M phosphate buffer of pH 8.0, and portions (240 µL) are passed in parallel through a column (10 cm x 2 mm) of sulfite oxidase immobilized on CNBr-activated Sepharose 4B and a blank column of Sepharose without the enzyme. The mobile phase is the 0.1 M phosphate buffer, and detection is by amperometry at +0.50 V in a flow-through cell fitted with a Pt-wire working electrode, a vitreous-carbon counter electrode and a reference Ag - AgCl (KCl) electrode. The difference in response for the streams with and without enzyme treatment is used to calculate the SO32- content. Typically, the calibration graph was rectilinear for 1 to 10 ppm of SO32-, the recovery was 94%, and the coefficient of variation at 5 ppm was 2.3% (n = 10). Response was maintained for 20 days and fell to 67% of the original value after 45 days for 5 ppm of SO32-. Results for red wine were erratic, showing that the gelatin treatment does not wholly prevent interference.
Sulfite Wine White Wine Red Amperometry Electrode Immobilized enzyme Buffer Column Interferences

"The Co-immobilization Of Alcohol Dehydrogenase, Diaphorase, And NAD On Glutaraldehyde-activated Sepharose"
Agric. Biol. Chem. 1989 Volume 53, Issue 8 Pages 2263-2265
Hiroyuki UKEDA, Masatomo IMABAYASHI, Kiyoshi MATSUMOTO and Yutaka OSAJIMA

Abstract: With the demonstrated use of noncofactor-requiring enzymes as bioreactors, attention is turning to the use of the more complex cofactor-requiring enzymes. Among these enzymes, the dehydrogenases requiring nicotinamide cofactors are of central interest. The most effective way to use dehydrogenases is to maintain both a nicotinamide cofactor, such as NAD, and the coupled dehydrogenases in one reactor and recycle the cofactor in silu. In our previous paper, we reported that yeast alcohol dehydrogenase (ADH) and native NAD could be coimmobilized on Sepharose gel modified repeatedly with hexamethylenediamine and glutaraldehyde. In this investigation, we have used this method to coimmobilize ADH, diaphorase (DI), and NAD. This coimmobilization gel contains a recycling system for NAD, permitting the recycling reaction to be coupled to consumption of dissolved oxygen using vitamin K3 as a mediator.
Ethanol Immobilized enzyme Sepharose beads

"Amperometric Flow Injection Measurement Of Protein In Dairy Products Using Glutaraldehyde"
Agric. Biol. Chem. 1987 Volume 51, Issue 10 Pages 2835-2836
Hiroyuki UKEDA, Shoko TANAKA, Kiyoshi MATSUMOTO and Yutaka OSAJIMA

Abstract: Protein was determined in dairy produce in a PTFE flow system (illustrated), based on simultaneous injection of glutaraldehyde and sample and then confluence before reaching the Clark O electrode (potential -0.8 V). Reaction was optimum at a glutaraldehyde concentration. of 10% and a reaction temperature of 30°C. The flow rate affected the rectilinear range and the slope of the calibration graph. Response was rectilinear from 1.0 to 4.0% of protein at 0.95 mL min-1, when 12 samples could be analyzed in 1 h. The limit of detection was 2 mM for L-glycine and 0.3% for nutrose (a Na salt of casein).
Protein Dairy Products Amperometry Electrode Heated reaction Merging zones

"Flow Injection Analysis Of Lactose In Milk Using A Chemically Modified Lactose Electrode"
Agric. Biol. Chem. 1985 Volume 49, Issue 7 Pages 2131-2135
Kiyoshi MATSUMOTO, Osamu HAMADA, Hiroyuki UKEDA and Yutaka OSAJIMA

Abstract: Milk was injected into a flow stream of 0.1 M phosphate buffer (pH 7.5) and mixed before electrochemical detection with β-D-galactosidase and glucose oxidase immobilized on a vitreous-carbon electrode (prep. described) and, to detect electrochemical interference, a non-enzymatic electrode at +0.95 V vs. a SCE. The calibration graph was rectilinear for 0.1 to 1.5 mM and the coefficient of variation (n = 10) was <2% with 0.4 mM lactose.
Lactose Milk Electrode Interferences Immobilized enzyme

"Study On The Sourness Of Food And Its Electrochemical Measurement. 7. Conductometric Flow Injection Analysis Of The Organic Acid Content In Citrus Fruits"
Agric. Biol. Chem. 1984 Volume 48, Issue 9 Pages 2211-2215
Kiyoshi MATSUMOTO, Koh-ichi ISHIDA, Takakazu NOMURA and Yutaka OSAJIMA

Abstract: A flow injection system, incorporating a flow-through four-electrode cell for controlled-potential conductance measurements, is described. For the analysis, a sample (35 µL) of pure centrifuged fruit juice was injected into the carrier stream (flow rate 20 mL min-1), and the mixing-coil length was 100 cm. There was good correlation (r = 0.992) between peak conductance and acid content (as shown by addition of malic and citric acids to the juice). By this method, 50 samples could be analyzed in 1 h, and the coefficient of variation of the results for any given juice was 0.5% (n = 20). To reduce the viscosity of the juice, dilution (1:3 or 1:4) before injection is recommended.
Acids, carboxylic Juice Conductometry Electrode Conductometry Standard additions calibration Viscosity

"Flow Injection Analysis Of Reduced Nicotinamide Adenine Dinucleotide Using β-naphthoquinone-4-sulfonate As A Mediator"
Agric. Biol. Chem. 1984 Volume 48, Issue 7 Pages 1879-1880
Kiyoshi MATSUMOTO, Hiroyuki UKEDA and Yutaka OSAJIMA

Abstract: This paper proposes the use of β-naphthoquinone-4-sulfonic acid potassium salt (β-NQ) as a mediator and the amperometric determination of NADH by measuring the anodic current (at + 0.1 V vs. SCE on a GCE) of reduced β-NQ.
Nicotinamide adenine dinucleotide reduced Amperometry Clinical analysis

"A Low-picomole Fluorimetric Detection System For Amino-acid Analysis"
Agric. Biol. Chem. 1984 Volume 48, Issue 6 Pages 1595-1601
Naoto Kondo, Kunio Imai, Minoru Isobe and Toshio Goto

Abstract: Amino-acids were analyzed by a method involving post-column derivatization with phthalaldehyde(I) and use of a non-switching NaClO flow system. The apparatus (illustrated) comprised a computer-controlled HPLC device with a three-solvent gradient mixer and a fluorimetric detector and permitted analysis for 17 amino-acids in 85 min with a stable baseline. Optimum concentration. and flow rates of NaClO and I solution were 0.002%; 0.22 mL min-1 and 0.16%; 0.26 mL min-1, respectively. Use of NaClO caused an ~30% decrease in fluorescence response of the usual amino-acids, except for proline and cystine, the latter being enhanced ~10-fold. Detection limits for proline and cystine were 500 and 1000 fmol, respectively; that of the other amino-acids was 100 fmol. Calibration graphs were rectilinear between 5 and 500 pmol. The system was applied to the enantiomeric analysis of glutamic acid and cysteic acid in studies of oxycadystin.
Amino Acids HPLC Fluorescence Post-column derivatization

"New Continuous-flow-monitoring System For Radioactive Amino-acids"
Agric. Biol. Chem. 1981 Volume 45, Issue 8 Pages 1881-1884
Satoshi MORI

Abstract: A continuous flow system consisting of a high-speed amino acid analyzer and a radioliq. analyzer is described for determining radiolabeled amino acids. The flow cell of the radio-liq. analyzer is packed with Li glass scintillator that fluoresces upon b-irradn. The amino acid analyzer was a column (4.5 x 300 mm) packed with Durrum DC 4A resin, with Li citrate buffer as eluant, and ninhydrin as detection reagent at 570 or 440 nm. The system was tested on the assimilation of proline-U-14C in barley roots. The system had a counting efficiency for 14C of ~45% and a detection limit for 14C of 0.25 nCi. In barley roots, the order of specific activity after 60 min was proline > glutamic acid > glutamine > GABA > aspartic acid > asparagine. After 120 and 180 min, the order was proline > aspartic acid > glutamic acid > glutamine > GABA > asparagine.
Amino Acids Glutamic acid Glutamine Aspartic acid l-asparagine 4-aminobutyric acid Barley Radiochemical