• KSBB Journal
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• v.13 no.1
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• pp.52-57
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• 1998

The present work proposes a simple electrochemical method applicable to any immobilization processes of oxidase using a Clark type oxygen electrode as a base transducer. The present work suggests an optimal immobilization technique among three different methods of glucose oxidase(GOD) onto one side of $37[\mu}$mthick blend membranes, composed o 80% of cellulose triacetate and 20% of polycaprolactone, on the basis of the maximum Michaelis-Menten parameter(Vm) determined by either steady state or transient analyses. The electrode system was made of disk type gold cathode(4mm diameter) and Ag/AgCl anode. One side of the blend membrane was in contact with the cathode surface while the other side was immobilized with GOD either in covalent-bond or cross-linked forms, the latter being covered by $25{\mu}$m thick dialysis membrane of cellulose acetate. The resultant current density was on-line monitored by a potentiostat while glucose level was varied from 1 to 20 mM. The present study shows that direct cross-linking of GOD with glutaraldehyde was mostly preferred for fabrication of glucose sensor, on the basis of resultant kinetic parameters from either steady state or transient analyses.

• The Korean Journal of Mycology
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• v.12 no.1
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• pp.21-26
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• 1984

Aspergillus awamori which produces glucoamylase was cultivated in the starch-Czapek-­Dox's medium in which sucrose was depleted. A rapid method for identification and assay of glucoamylase produced by the A. awamori in the culture was established by the use of the glucose oxidase. The levels of glucose derived from the breakdown of the starch medium were assayed by using glucose oxidase, which was proved to be effective in the screening of glucoamylase-producing fungi in terms of rapid and simple determination. After the cellulose acetate electrophoresis of the precipita ted culture broth, the glucoamylase band in the gel was contacted with 2% starch solution with glucose oxidase, and then color reaction was occurred. Also this method could be effective to identify rapidly the fungal glucoamylase.

• Journal of Environmental Health Sciences
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• v.8 no.2
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• pp.57-65
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• 1982

Saccharides in Korean honey have been analyzed by traditional wet chemical methods and several chromatographic technics gas, paper, column and thin layer chromatography. A simple, rapid and versatile method for the separation and determination of saccharides via high performance liquid chromatography were used eluting with $H_2O : CH_CN$ at 25:75, at a flow rate of 1.0ml/min. Acasia honey contained 36.8% fructose, 31.4% glucose, 1.7% sucrose and bush clover honey held 34.4% fructose, 32.3% glucose and 30% sucrose. Difference on the regional distribution were not found in the quantity of saccharides (42 species). The quality of inferior honey was assumed to contain much maltose, sugar and glucose than common honey.

• Proceedings of the Zoological Society Korea Conference
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• 1999.10b
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• pp.200.2-200
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• 1999

No Abstract, See Full Text

• Bulletin of the Korean Chemical Society
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• v.34 no.6
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• pp.1698-1702
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• 2013

Glucose is a common medical analyte measuring in human serum or blood samples. The development of a primary method is necessary for the establishment of traceability in measurements. We have developed an isotope dilution liquid chromatography tandem mass spectrometry as a primary method for the measurement of glucose in human serum. Glucose and glucose-$^{13}C_6$ in sample were ionized in ESI negative mode and monitored at mass transfers of m/z 179/89 and 185/92 in MRM, respectively. Glucose was separated on $NH_2P$-50 2D column, and the mobile phase was 20 mM $NH_4OAc$ in 30% acetonitrile/70% water. Verification of this method was performed by the comparison with NIST SRMs. Our results agreed well with the SRM values. We have developed two levels of glucose serum certified reference material using this method and distributed them to the clinical laboratories in Korea as samples for proficiency testings. The expended uncertainty was about 1.2% on 95% confidence level. In proficiency testings, the results obtained from the clinical laboratories showed about 3.6% and 3.9% RSD to the certified values. Primary method can provide the traceability to the field laboratories through proficiency testings or certified reference materials.

• Korean Journal of Food Science and Technology
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• v.17 no.1
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• pp.37-40
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• 1985

The reactor performance of a coimmobilized glucose oxidase and catalase enzyme system was investigated. In the determination of efficiencies of glucose oxidase and catalase of dual, mixed and soluble systems, the dual type immobilized one was superior to either the soluble or to the mixed system. In the continuous plugflow bed reactor system of glucose oxidase and catalase, $k-d$, deactivation rare constant of glucose oxidase only and catalase/glucose oxidase = 10 were $1.12\;{\times}\;10^{-2}\;and\;2.17\;{\times}10^{-3}\;hr^{-1}$, respectively. In the effect of ${\tau}$, space time, the point of $O_2$ limitation is $5.5\;g{\cdot}hr/l$ in both catalase/glucose oxidase = 1 and 10. In the effect of $O_2$ concentration to reduce the $O_2$ diffusion limitation, it appeared that ${\tau}\;=\;8.3g{\cdot}r/l$ is the maximum point of $O_2$ concentration in both catalase/glucose oxidase = 1 and 10.

• Journal of the Korean Chemical Society
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• v.37 no.10
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• pp.874-880
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• 1993

Spectrophotometric enzymatic analysis and amperometric enzymatic analysis for the determinations of glucose and ethanol were studied utilizing glucose oxidase (GO) and alcohol oxidase (AO), respectively, which commonly consume $O_2$ and produce $H_2O_2$. For the determination of glucose, $H_2O_2$ were coupled to $K_4Fe(CN)_6$ via peroxidase producing $K_3Fe(CN)_6$ whose absorbance was measured at 418 nm or whose diffusion current was measured on the glassy carbon electrode at an applied potential of -55 mV vs. Ag/AgCl (sat. KCl) reference electrode. Amperometric analysis was 1000 times more sensitive as well as 10 times better in the linear concentration range than spectrophotometric analysis. For the determination of ethanol, AO only was used for the enzymatic analysis, since $K_3Fe(CN)_6$ was completely disappeared as soon as AO was added. Either rate of $H_2O_2$ produced was amperometrically measured at +0.900 V or rate of $O_2$ consumed was measured at -0.500 V vs. Ag/AgCl(sat. KCl) reference electrode.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.50 no.5
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• pp.319-324
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• 2005

This study was conducted to identify the soluble carbohydrates in soybean seeds using on-line HPLC-RID-ES/MS and HPLC behavior, and to deter­mine their contents for high quality soybean breeding. The monosaccharide (glucose) and three oligosaccharides (sucrose, raffinose, and stachyose) were identified in Korean soybeans by their chromatographic behavior and results of on-line HPLC-RID-MS with Electro­spray Ionization mode. On the basis of HPLC with a RID detector, the 32 Korean major soybeans contain $0.37{\pm}0.26\%$ glucose, $4.55{\pm}0.91\%$ sucrose, $1.19{\pm}0.19\%$ raffinose, and $2.72{\pm}0.37\%$ stachyose on a dry basis. In 468 soybean germplasms, the ranges of glucose, sucrose, raffinose, and stachyose were $0.03 - 0.98\%$, $2.33 - 6.96\%$, $0.08 -1.87\%$ and $0.75 - 3.18\%$, respectively. Among 500 soybean samples, oligosaccharide contents of 32 Korean major cultivated soybeans and 468 soybean germplasms were varied $5.83 - 10.06\%$ and $3.66 - 10.32\%$, respectively. The composition of glucose, sucrose, raffinose, and stachyose in soluble carbo­hydrates of 500 soybean samples were $2.07 {\pm} 1.75\%$, $58.01{\pm}5.82\%$, $10.13{\pm}2.28\%$ and $29.80{\pm}4.54\%$, respectively. Sucrose appeared to be most prevalent in soy­bean soluble carbohydrates.

• Microbiology and Biotechnology Letters
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• v.23 no.5
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• pp.588-592
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• 1995

Fed-batch fermentation was used to produce the high concentrations of poly-$\beta $-hydroxybutyrate (PHB) and poly-$\beta $-(hydroxybutyrate-co-hydroxyvalerate) (PHB/V). Specific growth rate ($\mu $), yield of cell from glucose (Y$_{x/s}$) were calculated from the two samples in 3 to 5 hours of interval and they were reflected on the determination of glucose feeding rate to maintain the glucose concentration at around 10 g/l in the culture broth. PHB was accumulated after the nitrogen became limited at 60 g/l of dry cell weight by changing ammonia water to 4N-NaOH solution. As results, the final dry cell weight (DCW) of 170 g/l, PHB of 115 g/l were obtained in 50 hours and the overall productivity was 2.4 g/l$\cdot $h. After PHB accumulation, cosubstrate of glucose and propionic acid (PA) was fed to accumulate PHB/V. But, PA feeding rate was decreased from 3 g/l$\cdot $h to 1 g/l$\cdot $h to prevent PA from accumulating to high level in the broth, which is very inhibitory to the cells. As results, DCW, PHB and PHV were 147.5 g/l, 90 g/l and 8 mole % of hydroxyvalerate, respectively.

• Analytical Science and Technology
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• v.10 no.5
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• pp.362-369
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• 1997

Chemometric technique was applied to the sugar composition in five honeys of known botanical or geographical origin following HPLC. Fructose and glucose were predominant carbohydrates in honeys, and small amount of sucrose was also detected in one sample. Sugar contents in honeys samples were compared by the geographical or botanical origin. Fructose/glucose ratio ranged from 0.99 to 1.55 was obtained and these results are in good agreement with the ratio of literature. The plot of principal components analysis(PCA) showed that different honey samples grouped into distinct cluster by the geographical or botanical origin. Increasing the first or second principal component score, higher amount of sugar or less fructose/glucose ratio was observed in PCA plot. Chemometric approach was very useful to provide pattern recognition of sugar profile or quality indices of honey sample and to detect adulteration.