• Journal of the Korean Society of Food Science and Nutrition
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• v.46 no.1
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• pp.39-45
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• 2017

This study investigated the glycyrrhizic acid content and anti-diabetic activities of Glycyrrhiza uralensis (GU) depending on the cultivation region (Jecheon, Youngju, Gokseong, China, and Uzbekistan). Glycyrrhizic acid accuracy recovery and intra- and inter-day precisions (RSD%) of the method were calculated at 99.10~107.07% and 3.92 and 6.31% for GU samples, respectively, whereas the limits of detection and quantitation were 0.14 and $0.20{\mu}g/mL$. Anti-diabetic activity was measured by ${\alpha}-glucosidase$ and glucose uptake. GU (20 g) was extracted with 70% ethanol at $70^{\circ}C$ for 6 h. The Jecheon and Gokseong GU showed good inhibitory activity compared to the control. The Jecheon, Youngju, and Uzbekistan GU ethanol extracts ($100{\mu}g/mL$) showed glucose uptakes (in $C_2C_{12}$ myotube) of 124.19, 127.18, and 126.92%, respectively, compared to the positive control. In conclusion, these methods were validated for detection of glycyrrhizic acid in GU, and the results indicate that GU might have potential anti-diabetic activities.

• Archives of Pharmacal Research
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• v.13 no.1
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• pp.105-107
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• 1990

The absence, in the biomass, of glutamic-oxalacetic and glutamic-pyruvic transaminases and the prevalance of gamma-glutamic transpeptidase were taken as basic criteria to differentiate between Erwinia carotovora var. carorovora from E. carotovora var, citrullis and E. toxica. For further identification, detection of cholesterol in the biomass confirmed the toxica species whereas the absence of glucose confirmed the citrullis variety.

• KSBB Journal
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• v.14 no.3
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• pp.384-388
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• 1999

We have used high pH anion-exchange chromatography to analyze low level (below $20{\mu}M$) $\alpha$-D-glucose-1-phosphate (G-1-P) that can be used as a cytostatic compound, an antibiotic, and immunosuppressive drug. Our chromatographic method afforded excellent peak resolution and seletivity for glucose-6-phosphate and various maltooligosaccharides as well as G-1-P. The pulsed amperometric detector yielded linear response on G-1-P ranging from 2 - $20{\mu}M$, giving slope of $4.8{\times}10^4$(peak area/${\mu}M$). The detection limit was $2{\mu}M$. This method was applied to the purification of thermophilic $\alpha$-glucan phosphorylase from Thermus caldophilus. The technique will be extremely useful in future studies concerning carbohydrate metabolism in living organisms.

• Journal of the Korean Chemical Society
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• v.45 no.3
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• pp.223-229
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• 2001

A method for the determination of glucose in human whole blood by chemiluminescence method using a stopped flow injection system has been studied. The method is based on the differences in the chemiluminescence intensities of luminol due to the different amounts of hydrogen peroxide produced from the glucose oxidase catalyzed reaction. The enzyme reactor was prepared by immobilization of glucose oxidase on aminopropyl glass beads and the chemiluminescence from a flow cell was measured by means of an optical fiber bundle. In order to obtain the optimum experimental conditions, effects of pH for the chemiluminogenic solution and enzyme reactor, flow rate and temperature on the chemiluminescence intensity were investigated. The calibration curve obtained under optimum experimental conditions was linear over the range from $1.0{\times}10^{-1}$ mM to 7.0 mM and the detection limit was $6.0{\times}10^{-2}$ mM. The proposed method was applied to the determination of glucose in whole human blood sample and the results were compared with those obtained by an official method. The present method was also evaluated by the results of recovery experiments.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.31 no.2
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• pp.78-83
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• 2021

In this study, we prepared NiCo2O4 nanoparticles with large surface area by hydrothermal synthesis. In order to optimize the processing conditions for spinel NiCo2O4 nanoparticles with large surface area, experimental variables including concentration of Ni and Co precursor, reaction time, and temperature for post-heat treatment were evaluated. Optimized conditions for spinel NiCo2O4 with large surface area were [Ni]/[Co] 1:2 ratio, reaction time for 12 h, and post-heat treatment at 400℃. To investigate the feasibility as potential application for glucose sensor, electrochemical tests of the prepared NiCo2O4 nanoparticles in response to glucose was performed, which suggests that the NiCo2O4 can be suitable for a non-enzymatic-based electrochemical glucose sensor based on its high sensitivity and selectivity for glucose detection.

• 대한위암학회:학술대회논문집
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• 2002.10a
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• pp.24-33
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• 2002

Clinical application of positron emission tomography (PET) is rapidly increasing for the detection and staging of cancer at whole-body studies performed with the glucose analogue tracer 2-[fluorine-18]fluoro-2-deoxy-D-glucose (FDG). Although FDG PET cannot match the anatomic resolution of conventional imaging techniques in gastrointestinal and abdominal organs, it is particularly useful for identification and characterization of whole body at the same time. FDG PET can show foci of metastatic disease that may not be apparent at conventional anatomic imaging and can aid in the characterization of indeterminate soft-tissue masses. Most gastrointestinal cancer need to surgical management. FDG PET can improve the selection of patients for surgical treatment and thereby reduce the morbidity and mortality associated with inappropriate surgery. FDG PET is also useful for the early detection of recurrence and the monitoring of therapeutic effect. The gastrointestinal cancers, such as gastroeso-phageal cancer, colorectal cancer, liver cancer and pancreatic cancer, are common malignancies in Korea. PET is one of the most promising and useful methodology for the management of gastric cancer as well as other gastrointestinal cancers.

• Journal of Gastric Cancer
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• v.2 no.4
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• pp.184-190
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• 2002

Clinical application of positron emission tomography (PET) is rapidly increasing for the detection and staging of cancer at whole-body studies performed with the glucose analogue tracer 2-[fluorine-18]fluoro-2-deoxy-D-glucose (FDG). Although FDG PET cannot match the anatomic resolution of conventional imaging techniques in gastrointestinal and abdominal organs, it is particularly useful for identification and characterization of whole body at the same time. FDG PET can show foci of metastatic disease that may not be apparent at conventional anatomic imaging and can aid in the characterization of indeterminate soft-tissue masses. Most gastrointestinal cancer need to surgical management. FDG PET can improve the selection of patients for surgical treatment and thereby reduce the morbidity and mortality associated with inappropriate surgery. FDG PET is also useful for the early detection of recurrence and the monitoring of therapeutic effect. The gastrointestinal cancers, such as gastroesophageal cancer, colorectal cancer, liver cancer and pancreatic cancer, are common malignancies in Korea. PET is one of the most promising and useful methodology for the management of gastric cancer as well as other gastrointestinal cancers.

• BMB Reports
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• v.30 no.5
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• pp.326-331
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• 1997

To construct a competitive ELISA standard curve for the detection of glucose-6-phosphate debydrogenase (G6PD), we used highly purified native G6PD (nG6PD) as both immobilized and soluble antigens and anti-G6PD serum raised against nG6PD as antibody. The polystyrene cuvettes coated with nG6PD were challenged with a mixture of a limiting amount of anti-G6PD serum and various doses of nG6PD as competitors followed by incubation with alkaline phosphatase-anti-IgG conjugate. The competitive ELISA did not exhibit the typical sigmoidal dose-response curve characteristic of competition immunoassays under the optimal concentrations of antigen and antibody. The soluble nG6PD used as competitor failed to effectively inhibit the binding of antibodies to the immobilized nG6PD. The addition of NADP, a cofactor of G6PD enzyme, to coating buffer used for immobilizing nG6PD to the cuvettes and PBS-Tween-BSA buffer for diluting competitors did not improve the inhibition of antibody binding to immobilized nG6PD by soluble n/G6PD. The addition of BSA to coating buffer did not increase inhibition, either. Surprisingly, when partially active G6PD (paG6PD), obtained by repeated freeze-thawing, was used as competitor, the antibody binding to either immobilized nG6PD or immobilized paG6PD was inhibited 49-58%. We conclude that an effective competitive ELISA system with nG6PD enzyme and anti-G6PD serum for the detection of G6PD may not be established due to the poor inhibition of antibody binding to immobilized nG6PD by soluble nG6PD under the present assay conditions and that the inhibition may be improved by using an inactivated enzyme as competitor regardless of the type of immobilized antigen used. These results imply that the immobilized nG6PD may undergo denaturation upon binding to the polystyrene cuvettes and that our anti-G6PD serum may recognize denatured enzyme better than active enzyme.

• Journal of Microbiology and Biotechnology
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• v.17 no.11
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• pp.1826-1832
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• 2007

We describe the fabrication of poly(ethylene glycol) diacrylate (PEG-DA) hydrogel microstructures with a high aspect ratio and the use of hydrogel microstructures containing the enzyme ${\beta}$-galactosidase (${\beta}$-Gal) or glucose oxidase (GOx)/horseradish peroxidase (HRP) as biosensing components for the simultaneous detection of multiple analytes. The diameters of the hydrogel microstructures were almost the same at the top and at the bottom, indicating that no differential curing occurred through the thickness of the hydrogel microstructure. Using the hydrogel microstructures as microreactors, ${\beta}$-Gal or GOx/HRP was trapped in the hydrogel array, and the time-dependent fluorescence intensities of the hydrogel array were investigated to determine the dynamic uptake of substrates into the PEG-DA hydrogel. The time required to reach steady-state fluorescence by glucose diffusing into the hydrogel and its enzymatic reactions with GOx and HRP was half the time required for resorufin ${\beta}$-D-galactopyranoside (RGB) when used as the substrate for ${\beta}$-Gal. Spatially addressed hydrogel microarrays containing different enzymes were micropatterned for the simultaneous detection of multiple analytes, and glucose and RGB solutions were incubated as substrates. These results indicate that there was no cross-talk between the ${\beta}$-Gal-immobilizing hydrogel micropatches and the GOx/HRP-immobilizing micropatches.

• Korean Journal of Food Science and Technology
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• v.45 no.2
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• pp.156-160
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• 2013

A duplex polymerase chain reaction (PCR) method was developed to detect unapproved genetically modified (GM) potato (EH92-527-1) in Korea. The UDP-glucose pyrophosphorylase (UGP) gene was selected as an endogenous reference gene for potato and used to validate the specificity for 14 different crops. The primer pair EH92-F/R was designed to amplify the junction sequence between the genome and transgenic region introduced in GM potato. Its specificity was also validated using several different GM events. The detection limit of the duplex PCR method is approximately 0.05%. This duplex PCR method could be useful for monitoring cultivation of unauthorized GM potato in Korea.