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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Bioscience, Biotechnology, and Biochemistry

  • Publisher:
  • FAD Code: BBBC
  • CODEN: BBBIEJ
  • ISSN: 0916-8451
  • Abbreviation: Biosci. Biotechnol. Biochem.
  • DOI Prefix: 10.1271/bbb
  • Other Name(s): Agricultural and Biological Chemistry
  • Language: Japanese
  • Comments: Was Agricultural and Biological Chemistry until 1991 ISSN:0002-1369. Abstracts available from 1997 v61

Citations 8

"Highly Sensitive Flow Injection Analysis Of Lipid Hydroperoxides In Foodstuffs"
Biosci. Biotechnol. Biochem. 1996 Volume 60, Issue 11 Pages 1772-1775
AKASAKA Kazuaki TAKAMURA Tomoko OHRUI Hiroshi MEGURO Hiroshi HASHIMOTO Kenichi

Abstract: Edible oil, butter, margarine and mayonnaise samples were extracted with methanolic 50% butan-l-ol (details given). Portions (1-50 µL) of the extracts were injected into a carrier stream (0.8 ml/min) of methanolic 50% butan-l-ol, which merged a stream (0.3 ml/min) of 7.5 µg/ml diphenyl-l-pyrenylphosphine (reagent) in carrier solution containing 0.5 µg/ml 2,6-di-t-butyl-p-cresol, passed through a stainless-steel reaction coil (30 m x 0.5 mm i.d.) at 80°C then through a similar cooling coil (50 cm x 0.5 mm i.d.) prior to fluorimetric detection for lipid hydroperoxides at 380 nm (excitation at 352 nm). A second FIA system was also used which had a carrier stream flowing at 0.7 ml/min, a 30 µg/ml reagent stream flowing at 0.6 ml/min and a 50 m reaction coil. All other details were the same. For the first system the calibration graph was linear from 2-201 pmol trilinolein hydroperoxides (I), the detection limit was 2 pmol I and the RSD (n = 8) were 1.7-3.2%. For the second system, the calibration graph was linear from 0.4-79 pmol I, the detection limit was 0.2 pmol I and the RSD (n = 8) were 1.9-3.8%. Samples could be analyzed every 2 minutes, and results from both systems correlated well with those obtained by a batch method. Recoveries were 91.8-102%.
Lipids Hydroperoxide, lipid Trilinolein hydroperoxide Food Oil Food Food Sample preparation Fluorescence Heated reaction Method comparison

"Measurement Of L-malate Using Immobilized Enzyme Reactors Comparison Of Results Obtained With Four Different Enzymatic Systems"
Biosci. Biotechnol. Biochem. 1996 Volume 60, Issue 5 Pages 847-851
MATSUMOTO Kiyoshi HIGUCHI Seiichi TSUKATANI Tadayuki

Abstract: For the measurement of malate by an enzyme sensor, we did a comparative study using malate dehydrogenase (MDH) alone, MDH and glutamate oxaloacetate transaminase (GOT) together, a malic enzyme (ME) that requires NADP as a cofactor, and MDH and NADH oxidase together, With respect to the response of each reactor to 0.5 mM L-malate, the systems using ME alone and MDH plus NADH oxidase gave high values, The ranges of measurements were 0.05-1.00 mM (MDH alone), 0.01-0.05 mM (MDH plus GOT), 0.01-0.50 mM (ME alone) and 0.02-1.00 mM (MDH plus NADH oxidase), In the system with MDH alone, however, reducing sugars in the sample interfered with measurements and it was impossible to use this system for practical analysis of fruit samples, By contrast, the systems using ME alone or MDH plus NADH oxidase were unaffected by the presence of reducing sugars and were suitable for analysis of samples, Thus, the MDH-NADH oxidase system is recommended for practical analyzes of samples.
l-Malate Wine Fruit Amperometry Enzyme Interferences Immobilized enzyme

"Novel Enzymatic Assays For The Measurement Of Gallotannin, Amino-acids And Glutamate In Green Tea Infusions: Analytical Results"
Biosci. Biotechnol. Biochem. 1996 Volume 60, Issue 2 Pages 362-363
Lee, M.H.;Chen, R.L.C.;Matsumoto, K.

Abstract: Green tea infusions prepared by extracting tea with water at 85°C for 15 min were filtered and the filtrate or canned tea drinks were analyzed for gallotannin content by the method of Chen and Matsumoto (Anal. Sci., 1995, 11, 777) and amino-acid and glutamine content were measured by enzymatic FIA (Lee et al., Biosci. Biotech. Biochem., 1996, 60, 99). Scattergrams are presented of the results obtained to show the relationship between the three analytes. Results are discussed.
Glutamine Amino Acids Gallotannins Tea Enzyme

"Fluorometric Biosensing Of The Total Amino Acid Content And The Glutamate Content Of Green Tea Infusions Using An Automated Multi-channel Flow System"
Biosci. Biotechnol. Biochem. 1996 Volume 60, Issue 1 Pages 99-102
Lee, M.H.;Chen, R.L.C.;Matsumoto, K.

Abstract: An automated multi-channel continuous-flow analyzing system was constructed for the rapid measurement of both the total amino acid content and the L-glutamate content of green tea infusions. L-Glutamate in samples was oxidized and deaminated enzymatically in a channel with a mini-reactor that was packed with L-glutamate oxidase immobilized on glass beads, and the evolved ammonium ions were measured by a fluorogenic reaction with o-phthalaldehyde and β-mercaptoethanol. The total amino acid content was measured in a channel with another mini-reactor which was filled with immobilized L-amino acid oxidase. The fluorometric method is not subject to interference by reducing substances such as tea catechins and ascorbate, and the analytes in tea infusions were measured without pretreatment of samples. The use of this system for evaluation of tea quality was investigated.
Amino Acids Glutamate Tea Fluorescence Multichannel Immobilized enzyme Interferences Glass beads

"Specific Proline And Hydroxyproline Detection Method By Post-column Derivatization For High Performance Liquid Chromatography"
Biosci. Biotechnol. Biochem. 1995 Volume 59, Issue 9 Pages 1764-1765
Ozaki, A.;Shibasaki, T.;Mori, H.

Abstract: Samples (10 l) were applied to a Sumiciral OA-5000 column (25 cm x 4.6 mm i.d.) at 38°C and eluted (1 ml/min) with 1 mM aqueous copper sulfate. The eluate was mixed with 25 mM EDTA in 0.3 M borate buffer of pH 9.6 at a flow rate of 0.2 ml/min. Derivatization was carried out by adding 7-chloro-4-nitrobenzo-2-oxa-1,3-diazole in methanol (1 g/l) at a flow rate of 0.5 ml/min at 60°C. Detection was at 541 nm (excitation at 503 nm). Calibration graphs were linear from 7.6-7600 pmol-trans-4-hydroxy-L-proline. Other stereoisomers were detected by this method (results tabulated). This technique can be applied to the analysis of microbial hydroxyproline with good results.
l-Proline Hydroxyproline HPLC Post-column derivatization

"Biosensing Of Glucose, Sucrose, And Lactate In Beverages With An Automated Multi-channel Flow Analyzer"
Biosci. Biotechnol. Biochem. 1995 Volume 59, Issue 5 Pages 813-816
Chen, R.L.C.;Matsumoto, K.

Abstract: A multi-channel continuous-flow analyzer equipped with biosensing devices was developed for multicomponent measurement and its use in automating routine analysis was evaluated. Biosensing was achieved by the aid of an immobilized enzyme reactor installed in the channel, and the channel switching process for the sensing of a different compound was made by using a column-switching rotary valve. Another rotary valve was used for auto-sampling. Both of the two rotary valves were interfaced to a system controller and work conjugatively in a programmed manner. Signal subtraction between different channels was found to be more precise compared with the multi-channel flow injection analysis method, which is of merit for an analysis utilizing enzyme relay reaction (as for sucrose analysis) or for background signal subtraction. Glucose, lactate, and sucrose content in real samples were measured automatically with high reproducibility, and the results agree well with the kit method.
Glucose Sucrose Lactate Beverage Immobilized enzyme Valve Multichannel

"Multi-functional Flow Injection Biosensor For The Simultaneous Measurement Of Creatinine, Glucose And Urea"
Biosci. Biotechnol. Biochem. 1993 Volume 57, Issue 2 Pages 191-194
Rui, C.S.;Ogawa, H.I.;Sonomoto, K.;Kato, Y.

Abstract: A manifold is described (diagram given) incorporating enzyme reactors containing urease, creatinine deiminase, glutamate dehydrogenase, glutamate oxidase and glucose oxidase, delay coils and an O electrode. The flow stream was split into three channels, those passing through the urease and creatinine deiminase reactors were merged before passing through the glutamate dehydrogenase and glutamate oxidase reactors. All streams were merged before passing to the O electrode. The working solution was 67 mM Na - K phosphate buffer solution (pH 8.0) containing 0.1 mM EDTA, 0.3 mM NADH and 5 mM 2-oxoglutarate. Calibration graphs were rectilinear from 0.2 to 5 mM creatinine, 0.2 to 10 mM glucose and from 0.5 to 20 mM urea. The removal of endogenous interfering substances such as NH3 may allow the analysis of urine with this system.
Creatine Glucose Urea Urine Sensor Multidetection Interferences

"Development Of Analytical Method For Selective Detection Of Cardenolides By High Performance Liquid Chromatography"
Biosci. Biotechnol. Biochem. 1992 Volume 56, Issue 6 Pages 967-967
Baku Maekawaa & Kazuo Morimoto

Abstract: Cardenolides were separated on a column (25 cm x 4.6 mm) of TSK-gel ODS 120T operated at 25°C, with gradient elution (1 mL min-1) with aqueous methanol (details given). The eluate was mixed with Kedde reagent and passed through a reaction coil (5 m x 0.33 mm) followed by detection at 540 nm. The method compares well with the method using UV detection at 220 nm. The method is suitable for the analysis of cardenolides biotransformed by plant cell cultures.
Cardenolides Fermentation broth HPLC Spectrophotometry Post-column derivatization