• Journal of Pharmaceutical Investigation
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• v.29 no.4
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• pp.287-293
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• 1999

Transport study of horseradish peroxidase and transferrin-horseradish peroxidase conjugate was performed using an in vitro Caco-2 cell cultured monolayer grown on a polycarbonate membrane of $Transwell^{\circledR}$, Horseradish peroxidase was not transported across Caco-2 cell monolayer. Transferrin-horseradish peroxidase conjugate was transported through Caco-2 cell monolayer. The apparent membrane permeability coefficient $(P_{app})$ of transferrin horseradish peroxidase conjugate was $6.54{\times}10^{-7}\;cm/sec$. The $P_{app}$ value of transferrin-horseradish peroxidase conjugate across Caco-2 cell monolayer was increased to $11.9{\times}10^{-7}\;cm/sec$ in the presence of $50\;{mu}g/ml$ brefeldin-A. These results suggest the transferrin receptor mediated transcytosis of transferrin-horseradish peroxidase conjugate across Caco-2 cell monolayer.

• KSBB Journal
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• v.13 no.5
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• pp.599-605
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• 1998

Soybean peroxidase was extracted from soybean hulls and purified by ammonium sulfate precipitations (25% and 75% saturation), pl fractionation, and anionic exchange and gel filtration chromatographies (DEAE-Sephadex A-50 and Superose 12). Modlecular weight and pl value were estimated to be ca. 45 kD and 4.2, respectively. Purified soybean peroxidase had an RZ value of 0.43. Compared with horseradish peroxidase, it showed superior thermal and pH stability. Assuming the first-order kinetics, the thermal deactivation rate constant of soybean peroxidase at 80$^{\circ}C$ was about 8 times lower than that of horseradish peroxidase. Deactivation energy was calculated to be 69.3 kcal/mol. Soybean peroxidase showed about 10% higher H2O2 degradation capacity than horseradish peroxidase. Exploiting these advantages, the soybean peroxidase purified from the domestic soybean hull is expected to replace horseradish peroxidase in various applications.

• Applied Biological Chemistry
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• v.22 no.1
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• pp.24-27
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• 1979

A study was carried out about the effect of free fatty acids and lecithin on the thermal inactivation of horseradish peroxidase. In presence of lecithin peroxidase was inactivated very rapidly at $70^{\circ}C$ and pH 7.0, and showed also a rapid inactivation curve at $0^{\circ}C$ and pH 4.0. Linoleic acid was more effective in an $O_2-stream$ than in a $N_2-stream$, but oleic acid showed a similar tendency in the presence of $O_2-and\;N_2$ stream. From the results of the experiment we suggested that the opening of the heme crevis of peroxidase in the presence of lecithin and the produced lipidperoxide from linoleic acid may accelerate the thermal inactivation of horseradish peroxidase respectively.

• The Korean Journal of Food And Nutrition
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• v.8 no.1
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• pp.37-42
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• 1995

The amino acid sequence of basic isozyme 55 of Horseradish Peroxidase (HRP E5) was determined by protein sequencing. HRP E5 consisted about 300 residues, and has a molecular weight of approximately 36,000 $\pm$ 500 dalton. The protein was rich In aspartic acid (14%), arginine(13%), and leucine(11%). The primary structure of HRP E5 was established by sequencing its tryptic (T1-T19) and lysylendopeptic (Al-A3) peptides. The sequence homology between HRP E5 and HRP C (neutral isozyme of horseradish peroxidase) is found to be more than 66%. The highest concentration of identical residues are found on residues 29~56, 90~123, and 155~173, but relatively low on 174~271.

• KSBB Journal
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• v.15 no.1
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• pp.22-26
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• 2000

Kraft Lignin which is produced abundantly in pulp industry, was chemically degraded into small oligomers and polymerized using horseradish peroxidase. Lignin acidolysis was optimized by controlling reaction time and HCI concentration. Acidolyzed lignin was polymerized and copolymers of acidolyzed lignin and phenol or p-cresol were synthesized. 70% of kraft lignin was degraded after acidolysis. Number average molecular weight of all lignin polymers were from 8,500 to 14,000 and did not show large difference. Differential scanning calorimeter analysis showed that acidolyzed lignin did not show any melting temparature under $300^{\circ}C$, which indicates that newly synthesized lignin polymers can be used in industry under mild condition.

• KSBB Journal
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• v.14 no.4
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• pp.465-469
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• 1999

Horseradish peroxidase(HRP) in organic solvent can be reactivated by evaporation. In order to measure the evaporation effect, the enzyme solutions were obtained by evaporation and dilution of organic solvent, respectively. Although two situations were thermodynamically identical, the activity from evaporation was higher than that from dilution. From the UV absorbance and the fluorescence intensity mesurements, it can be explained that reactivation of enzyme activity might be caused by reversible folding, and the enzyme obtained by evaporation was more refolded than that obtained by dilution.

• Korean Journal of Veterinary Research
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• v.33 no.4
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• pp.611-615
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• 1993

A rapid, solid-phase microtitre plate enzyme immunoassay(EIA) to determine the concentration of progesterone and testosterone in dairy cow is described. Both steroid hormones were analysed employing antibodies against $11{\alpha}$-hemisuccinate-progesterone bovine serum albumin and 4-androsten-$17{\beta}$-ol-3-one-carboxymethyloxime bovine serum albumin, respectively. as primary antibodies and sheep Ig G as secondary antibody. The conjugated used as labels for progesterone and testosterone was progesterone-$11{\alpha}$-hydroxy-hemisuccinate- horseradish peroxidase and 4 ${\alpha}$-androsten-$17{\beta}$-ol-3-hemisuccinate- horseradish peroxidase, respectively. Detection limit of microtitre plate EIA was 6.7 pg/well for progesteone and 1.0 pg/well for testosterone.

• Bulletin of the Korean Chemical Society
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• v.25 no.7
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• pp.997-1002
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• 2004

A hydrogenperoxide sensor containing peroxidase extracted from horseradish was constructed and pH effect on its sensing ability was investigated. Current profiles of the biosensor with pH and the electrophoretic analysis showed that horseradish peroxidase consists of two isozymes. Assuming that it is a hypothetical twoisozyme mixture, the current profiles were deconvoluted into two Gaussians. Application of the new Michaelis-Menten equation connoting pH concept to this system enabled to find all the related dissociation constants of the isozyme-substrates and the isozyme-proton complexes and to determine pHs for the maximal isozyme activities.

• Biotechnology and Bioprocess Engineering:BBE
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• v.11 no.5
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• pp.462-465
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• 2006

An important issue in the oxidation of pentachlorophenol (PCP) by the enzyme horseradish peroxidase (HRP) is enzyme inactivation during the reaction. This study was initiated to investigate the ability of two nonionic surfactants (Tween 20 and Tween 80) to mitigate HRP inactivation. The surfactants were tested at concentrations below and above their critical micelle concentrations (CMCs). Enhancement of PCP oxidation was observed at sub-CMCs, indicating effective protection of HRP by the two surfactants. Maximum levels of PCP removal were observed when the concentrations of Tween 20 and Tween 80 were 40 and 50% of the CMCs, respectively At supra-CMCs, both surfactants caused a noticeable reduction in the extent of PCP removal.

• KSBB Journal
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• v.16 no.2
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• pp.179-182
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• 2001

The use of 2,2-azinobis(3-ethylbenzthiazoline-6-sulfonic acid)(ABTS) as a radical mediator enhanced the bleaching efficiency of kraft pulp by horseradish peroxidase(HRP) and $H_2O_2$. High concentrations of up to 20 mM $H_2O_2$. were used. The bleaching of the kraft pulp increased as the amount of HRP and ABTS concentration were inceased up to 0.3 mg/90 mL and 2 mM, respectively. The bleaching of the kraft pulp was closely related with the HRPs activity and its adsorption onto the pulp. The activity of HRP and bleaching of kraft pulp were maximum at pH 7 and were reduced either in a acidic or alkaline solutions. The adsorption of HRP onto pulp was low in solutions of pH 6-8 and high in an acidic(pH5) and an alkaline solutions(pH 9). The adsorption of the enzyme was greater for alkali-lignin than for crystalline cellulose, the two major components of pulp.