• Korean Journal of Environmental Agriculture
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• v.15 no.1
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• pp.37-45
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• 1996

Abstracts From the previous metabolic study of Pentachlorophenol(PCP), PCP was found to be exclusively transformed into ${\beta}-glucose$ conjugates of PCP in soybean and rice cell suspension cultures. In order to gather structural information of of the glucose conjugate, their aglycons and glycon have been analyzed by GC and GC/MS respectively, after thorough purification by chromatographic techniques. The glucose conjugates were effectively purified through a 1-butanol extraction followed by Silica gel TLC, Sephadex column chromatography and HPLC. Aglycons of the metabolites were identified as PCP, isomeric mixture of tetrachlorophenol, and tetrachlorocatechol and glycon were identified as glucose, suggesting that there are at least three kinds of glucose conjugates with different phenolic moieties. Under controlled conditions, the glucose conjugates were separated into three HPLC peaks which released respective aglycon upon a hydrolytic treatment. These results give valuable information on the structure of the glucose conjugates such that some PCP-driven chlorophenols, in addition to PCP, are also conjugated with glucose.

• Korean Journal of Environmental Agriculture
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• v.15 no.2
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• pp.167-178
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• 1996

In order to identify PCP glucose conjugates transformed from PCP in soybean and rice cell suspension cultures, the purified metabolites were acetylated, purified twice by HPLC using a normal and a reversed phase column, and then subjected to fast atom bombardment(FAB) mass spectrometric analysis. As were the conjugates, their acetylated derivatives of the glucose conjugates formed at the early stage(48 hr) of metabolism were separated by HPLC into three fractions. FABMS analysis of each fraction revealed that, at least in two fractions, the locations of the spectral peaks were practically coincident with those deducible from the structures of pentachlorophenyl and tetrachlorophenyl ${\beta}-D-glucopyranosides$. Based on information obtained from mass spectral and chromatographic analysis of not only the water-soluble metabolites but also aglycones and glycone, it is concluded that PCP is primarily metabolized to glucose conjugates, which account for more than 50% recovery of the PCP-conveyed radioactivity from the water soluble metabolites : The conjugates are mainly made up of pentachlorophenyl ${\beta}-D-glucopyranoside$, tetrachlorophenyl ${\beta}-D-glucopyranosides$( probably 2 or more isomers), and 2-hydroxy-3,4,5,6-tetrachlorophenyl ${\beta}-D-glucopyranoside$.

• Korean Journal of Environmental Agriculture
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• v.11 no.3
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• pp.215-223
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• 1992

A metabolic study has been conducted to investigate the conversion of pentachlorophenol(PCP) to water soluble metabolites in soybean and rice cell suspension cultures as well as in intact rice plants. PCP in plant cells was found to be exclusively transformed into water soluble metabolites. The relative rate of the metabolic conversion of PCP in decreasing order was soybean cultures > rice cultures > rice plants. Also observed was that, the older the cultures grown, the lower the conversion rate was. Primary water soluble metabolites isolated from both the 5 day old soybean and 8 day old rice cells were specifically hydrolyzed only by ${\beta}$-glucosidic linkage specific glucosidase, suggesting that the metabolites are ${\beta}$-glucose conjugates. The amount of glucose conjugates was increased with increasing time of incubation of PCP up to 24 hr in both soybean and rice cultures; Thereafter, it was decreased progressively. Most of the glucose conjugates were further metabolized to more polar conjugates in cells, but a portion of them was excreted into the culture medium.

• Journal of Microbiology and Biotechnology
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• v.28 no.2
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• pp.298-304
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• 2018

The single-vessel multienzyme UDP-${\alpha}$-$\text\tiny{D}$-glucose recycling system was coupled with a forward glucosylation reaction to produce novel glucose moiety-conjugated derivatives of different tetracycline antibiotic analogs. Among five tetracycline analogs used for the reaction, four molecules (chlorotetracycline, doxytetracycline, meclotetracycline, and minotetracycline) were accepted by a glycosyltransferase enzyme, YjiC, from Bacillus licheniformis to produce glucoside derivatives. However, the enzyme was unable to conjugate sugar units to rolitetracycline. All glucosides of tetracycline derivatives were characterized by ultraviolet absorbance maxima, ultra-pressure liquid chromatography coupled with photodiode array, and high-resolution quadruple time-of-flight electrospray mass spectrometry analyses. These synthesized glucosides are novel tetracycline derivatives.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2001.05a
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• pp.297-298
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• 2001

Numerous studies have shown that ascorbic acid is an indispensable micronutrient required to maintain the physiological processes of different animals including most of fishes. L-ascorbyl-2-glucose (AA2G) is an $\alpha$-glucose conjugate of AA on the C-2 position and a newly found AA derivative front Kimchi, Korean traditional fermented vegetable food, AA2G s stable to ascorbate oxidase and heating, it can be effectively hydrolyzed in vitro by the rice seed $\alpha$-glucosidase. (omitted)

• Bulletin of the Korean Chemical Society
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• v.18 no.5
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• pp.515-519
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• 1997

In a competitive enzyme immunoassay, the performance was tested with different analyte-enzyme conjugates (signal generators) in their binding constants to antibody. Analyte (progesterone)-enzyme (glucose oxidase; GO) conjugates were chemically synthesized and purified by using a gel column with an immobilized antibody to progesterone. In an elution range from the column, four peaks were detected by measuring total enzyme activities. Results from further analysis indicated that the first peak contained mainly unreacted GO while the next three peaks conjugated GO with progesterone. These three conjugate preparations were compared in dose-response curves along with the unpurified mixture. The purified conjugates showed higher detection capabilities than did the mixture. Especially, the preparation in the second peak next to the free GO peak improved the detection limit five times. This performance was comparable to that of a progesterone-horseradish peroxidase conjugate that has been identified to have one progesterone ligand.

• Food Science and Biotechnology
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• v.14 no.6
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• pp.743-746
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• 2005

A dipstick-type immunochemical biosensor for the detection of the organophosphorus insecticide fenthion was developed using a screen-printed electrode system as an amperometric transducer with polyclonal antibodies against fenthion as a bioreceptor. The assay of the biosensor involved competition between the pesticide in the sample and pesticide-glucose oxidase conjugate for binding to the antibody immobilized on the membrane. This was followed by measurement of the activity of the bound enzyme by the supply of the enzyme substrate (glucose) and amperometric determination of the enzyme reaction product ($H_2O_2$). The activity of the bound enzyme was inversely proportional to the concentration of pesticide. The optimized sensor system showed a linear response against the logarithm of the pesticide concentration ranging from $10^{-2}$ to $10^3\;{\mu}g/L$.

• YAKHAK HOEJI
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• v.48 no.6
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• pp.369-373
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• 2004

We previously reported that Streptococcus pneumoniae capsule attached to the surface protein (JY-Pol) was protective to systemic pneumococcal infection. The JY -Pol antigen induced IgM, IgG, and IgA in mice and provoked cell-mediated immunity. In this current study, we investigated the effect of anti JY-Pol antiserun and monoclonal antibody C2 (Mab C2) specific for the JY-Pol antigen against the pneumococcal disease. Mice that were given the antiserum survived longer than mice that received antiserum pre-absorbed with S.pneumoniae cells or DPBS as a negative control. Heat-treated anti JY-Pol antiserum resulted in survival rates similar to intact fresh JY-Pol antiserum. Mab C2 isolated from JY-Pol-immunized mice also enhanced resistance of naive mice against the pneumococcal diseaser. This protection by Mab C2 appeared to be mediated by opsonization as determined in a RAW 264.7 monocyte/macrophage cell line. Epitope analysis showed that Mab C2 epitope consisted of glucuronic acid and glucose that blocked the interaction of JY-Pol to the C2. Taken together, these data indicate that the antiserum induced by the JY-Pol, a naturally pneumococcal conjugate formula, mediated the protection by passive transfer, which was confirmed by protective effect of Mab C2.

• Journal of Microbiology and Biotechnology
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• v.17 no.6
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• pp.1002-1009
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• 2007

A rapid, convenient homogeneous competitive enzyme immunoassay for estimating the amount of fenthion is described. The assay utilizes glucose-6-phosphate dehydrogenase-hapten conjugates that are inhibited in solution by antibodies obtained from bovine serum albumin-hapten conjugates. In order to investigate the effects of bridging group recognition on the sensitivity of dose response characteristics, the bridging groups of varying alkyl chain length were attached at the phosphate position of fenthion. Among the antibodies used, the one obtained from the use of hapten (fenthion analog) with the same bridging group structure that was used in preparing the enzyme-fenthion conjugates showed maximum inhibition (up to 51.8%) in the absence of fenthion. In the presence of fenthion, the activity of the enzyme-hapten conjugate is regained in an amount proportional to the fenthion concentration. Under the optimized condition, the $ED_{50}$ value for fenthion was $0.809{\mu}g/ml$. The assay developed in this study is a rapid effective screening method for fenthion prior to precise analysis.

• Proceedings of the IEEK Conference
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• 2005.11a
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• pp.755-758
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• 2005

This paper describes the novel immunoassay sensing system for a portable clinical diagnosis system. It consists of a bead cage reactor and a CMOS integrated biosensor. It showed the simple and easy antibody coating method on beads by flow-through avidin biotin complex technology in a microfluidic device. It showed just 90 nL sample consumption and good result for the application of alpha feto protein. The bead cage reactor has the role of the antibody coating, antigen binding and enzyme linking for the electrochemical sensing method. The CMOS biosensor consists of ISFET (ion selective field effect transistor) biosensor and temperature sensor for detecting pH that is the byproduct of enzyme reaction. The sensitivity is 8 $kHz/^{\circ}C$ in a temperature sensor and 33 mV/pH in a pH sensor. After filling the 15 um polystyrene beads in bead cage, antibody flowed and reacted to beads. Subsequently, the biotinylated antigen flowed and bound to the antibody and GOD (glucose oxidase)-avidin conjugate flowed and reacted to the biotin of the biotinylated antigen. After this reaction process, glucose solution flowed and reacted to the GOD on beads. The hydrogen was generated by glucose-GOD reaction. And it was detected by the pH sensor.