• Journal of Korea Foresty Energy
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• v.20 no.1
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• pp.35-41
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• 2001

Lignin model compounds I-lV were pyrolyzed at 315$^{\circ}C$. The mixture compounds pyrolized were analyzed by GC-MS spectrometry. The results were summarized as follows : 1. From the pyrolysis of lignin model compound I and II, 0.45mo1 of guaiacol, 0.5mol of dimethoxyphenol(DMP), and 0.12 and 0.23mo1 of dimethoxyacetonphenone(DMAP) were produced respectively. 2. In the pyrolysis of lignin model compound III and IV, 0.26mol of guaiacol, 0.30mo1 of DMP, and 0.09 and 0.15mo1 of trimethoxyaretonphenone(TMAP) were produced respectively 3. Pyrolysis mechanism of lignin model compounds are dehydrated at first, and $\beta$-04 linkage cleavaged, and then guaiacol, DMP, DMAP and TMAP were produced. The above results show that lignin model compound I and II produce more aromatic compounds than lignin model compound III and IV. This is reason that veratryl unit structures may pyrolize easier than trimethoxyphenol unit structures. The closer research is proceeding.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.12 no.2
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• pp.95-102
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• 1979

Brevibacterium flavum treated with phenol derivatives, guaiacol and o-vanillin has been revealed the marked increased ability in glutamic acid fermentation as 14.2 g/l in o-vanillin treated, 12.5 g/l in guaiacol treated while the 7.0 g/1 in nontreated cell. The increased ability of phenol derivatives treated cells in glutamic acid fermentation was ascribed to the formation of charge-transfer complex between phenols and oxygen. The charge-transfer complex effectively supply the oxygen to the fermention system in spite of high potential gradient in oxygen transfer formed by high cell concentration as insulator on film of air-liquid interface.

• Restorative Dentistry and Endodontics
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• v.6 no.1
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• pp.27-35
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• 1980

This study was to evaluate the effectiveness of a few disinfectant on amputated pulps of domestic dogs. The materials employed for the purpose were zinc oxide eugenol paste, calcium hydroxide as control groups and guaiacol (1%, 5%, 10% by weight) added zinc oxide eugenol paste and formaldehyde (1%, 5%, 10% by weight) added calcium hydroxide as experimental groups. Following were the results obtained throngh histo-pathological examination. 1) In calcium hydroxide-formaldehyde groups, secondary dentin formation was observed in the 2 weeks, but the remaining pulp tissue was severely atrophied according to the concentration of formaldehyde and the time increased. 2) In zinc oxide eugenol-guaiacol groups, the first evidence of secondary dentin formation was observed in the 3 weeks. It seems that the concentration variety of guaiacol influenced very little to the potential ability of dentin formation. 3) Except 1% formaldehyde containing calcium hydroxide group, every group showed severe pulp degeneration. In all groups of zinc oxide eugenol-guaiacol cases revealed the tendency of recovery.

• International Journal of Industrial Entomology and Biomaterials
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• v.12 no.1
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• pp.21-28
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• 2006

Peroxidase activity was measured in brown leaf spot pathogen (Myrothecium roridum) inoculated potted mulberry (Morus alba) during pre-symptomatic to various symptom development stages and compared with corresponding healthy leaf tissues. The enzyme showed a pH optimum of 7.0 and the activity was linearly increased up to 15 min of incubation. The peroxidase had a broad substrate specificity and the rates of oxidation were in the rank of pyrogallol> guaiacol> ascorbate at pH 7.0. Catechol at 10 mM inhibited 89% of guaiacol-peroxidase and 76% pyrogallol-peroxidase activities, indicated higher non-specific peroxidation in pyrogallol dependent assay system in mulberry than guaiacol. The optimum requirement for the guaiacol dependent assay was 0.2 ml (${\approx}40-60{\mu}g$ equivalent of protein) of crude enzyme source. Excepting the 8th leaf from the apex, the peroxidase activity did not vary appreciably in different leaf positions. In pre-symptomatic phases, an initial (1 to 5 min) rise of peroxidase activity was noticed in inoculated leaves, and then maintained a plateau up to 300 min. In contrary, non-infected tissue showed a slightly increased trend of enzyme level up to 420 min. In infected tissue, a sharp transient increase (3.1 fold) of peroxidase activity appeared between 300 - 420 min post infections. Afterwards, significantly different but steady maintenance of enzyme levels were observed in two treatments. On the other hand, during symptom development, a sharp increase in peroxidase activity was noticed up to 4th grade of lesion appearance (25.1 % to 50% of leaf area infection), and then declined slightly. However, in non-infected but same age healthy leaves, such huge fluctuations of enzyme level did not apparent. A high positive correlation $(R^2=0.92)$ between peroxidase activity and leaf spot development grades was also marked. The result implies that pre-symptomatic burst (between 1 - 5 and 300 - 420 min) and subsequent increased trend of guaiacol peroxidase activity may require for the symptomatic manifestation of Myrothecium leaf spot in mulberry.

• Journal of Microbiology and Biotechnology
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• v.17 no.4
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• pp.600-603
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• 2007

The effect of a water-miscible ionic liquid, 1-butyl-3-methylimidazolium tetrafluoroborate $([BMIM][BF_4])$, on the horseradish peroxidase (HRP)-catalyzed oxidation of 2-methoxyphenol (guaiacol) with hydrogen peroxide $(H_2O_2)$ was investigated. HRP maintains its high activity in the aqueous mixtures containing various concentrations of the ionic liquid and even in 90% (v/v) ionic liquid. In order to minimize the effect of solution viscosity on the kinetic constants of HRP catalysis, the enzymatic reactions in the subsequent kinetic study were performed in water-ionic liquid mixtures containing 25% (v/v) ionic liquid at maximum. As the concentration of $[BMIM][BF_4]$ increased for the oxidation of guaiacol by HRP, the $K_m$ value increased with a slight decrease in the $K_{cat}$ value: The $K_m$ value increased from 2.8 mM in 100% (v/v) water to 22.5mM in 25% (v/v) ionic liquid, indicating that ionic liquid significantly weakens the binding affinity of guaiacol to HRP.

• Applied Biological Chemistry
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• v.30 no.3
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• pp.219-226
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• 1987

Peroxidase isozyme C was isolated from mung bean cotyledon and purified to homogeneity as ascertained by chromatography and polyacrylamide gel electrophoresis, and then crystallized. Purification procedures included ammonium sulfate precipitation and column chromatography on Sephadex G-75, DEAE-cellulose and DEAE-Sephadex A-50. Peroxidase isozyme C was purified about 63 fold with 5% recovery. Isozyme C showed optimal activity at pH 5.0 with o-dianisidine and at pH 6.0 with guaiacol as substrate, and the optimal temperature was $70^{\circ}C$. Molecular weight of 50,000 was estimated for the isozyme C by SDS-polyacrylamide gel electrophoresis. At $70^{\circ}C$, it took 30 min to inactivate the isozyme to 50%, and at $80^{\circ}C$, this isozyme was almost completely inactivated in 20 min. The Km value of isozyme C for o-dianisidine was 0.11mM and that for guaiacol was 60.98mM using hydrogen peroxide as cosubstrate, and the kinetic pattern showed a competitive cyanide inhibition with respect to substrate. The crystalline structure of isozyme C was rectangular in shape.

• Analytical Science and Technology
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• v.26 no.5
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• pp.299-306
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• 2013

Pyroligneous liquor as a byproduct from charcoal production of bamboo sprout produced damyang-gun has the broad benefits such as improvement of soil quality, plant growth control and is mainly used for the treatment of atopic dermatitis, fungi and many other skin diseases. In this study, flavor compounds of pyroligneous liquor from bamboo sprout produced in Damyang-gun were analyzed and compared using three different methods including direct analysis (DA), headspace solid phase microextraction (HS-SPME) and stir bar sorptive extraction (SBSE). Simultaneously, the analytical conditions of GC-MS for the determination of volatile compounds were optimized. Based on volatile organic compounds detected by GC-MS, SBSE and SPME methods showed higher sensitivity than direct analysis. Major compounds of pyroligneous liquor were cresol, guaiacol, p-ethyl guaiacol and syringol. These phenolic compounds are reported as the useful chemicals with medicinal activity.

• The Korean Journal of Mycology
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• v.39 no.1
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• pp.48-52
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• 2011

Breeding of Lentinula edodes generates a number of hybrid strains that are subject to evaluation for good traits for the mushroom production. As an effort to understand biochemical properties of the hybrid strains, this study tried to develop a fast and easy method for comparison of the ability of producing extracellular laccase among hybrid strains of Lentinula edodes. For this aim, we estimated the effect of media types and chromagenic chemicals on the detection of extracellular laccase in seven hybrid strains of L. edodes. When Remazol Brilliant Blue R (RBBR) dye was used for chromagenic reaction, the detection of the enzyme activity was feasible both in the solid and liquid media containing not potato dextrose but malt extract as a nutrient component. When guaiacol was used for chromagenic reaction, the detection of the enzyme activity was feasible both in the solid and liquid media containing either potato dextrose or malt extract as a nutrient component. Malt extract-based liquid culture with RBBR or guaiacol in 2 ml microfuge tube allowed us to economically and quantitatively detect and compare the enzyme activity within 3 days among the tested hybrid strains of L. edodes.

• The Korean Journal of Food And Nutrition
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• v.20 no.1
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• pp.9-13
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• 2007

In this study, sesame oils and sesame meals(A, B) were obtained from roasted sesame at $200^{\circ}C$ and $220^{\circ}C$, respectively. The total volatile component(VC) contents of these samples(A, B) were as follows : The sesame oils had 1,397.1 ppm and 1,518.8 ppm, and the sesame meals had 663.2 ppm and 775.3 ppm for samples A and B, respectively : sesame flavor was16,507.9 ppm, The major VCs in the sesame oils were pentane, 2-butanone, pyrazine, methylpyrazine, 2,5- and 2,6-dimethyl pyrazine, furfuryl alcohol, guaiacol and 4-vinylguaiacol. The pyrazine contents of the seasame oils were 834.4 ppm and 816.4 ppm for samples A and B, respectively. The major VCs in the sesame meals were 2-butanone, hexanal, pyrazine, methyl pyrazine, 2,6-dimethyl pyrazine, furfuryl alcohol, and so forth. For artificial sesame flavor, the total VC content was 16,507.9 ppm, and the major VCs were 2-butanone, guaiacol, and 4-vinylguaiacol. Approximately 35.02% of the total VC content of sesame flavor was composed of 2-butanone, guaiacol, and 4-vinylguaiacol, and these constituted more than 1,000 ppm of its total VC content.

• Proceedings of the Zoological Society Korea Conference
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• 1996.10a
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• pp.182.2-182
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• 1996