• Journal of the Korean Wood Science and Technology
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• v.35 no.6
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• pp.91-99
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• 2007

Activities of the extracellular enzyme from Fomitopsis palustris, a brown-rot fungi, and by which crystallinity changes of cellulose in the various softwoods, such as Larix leptolepsis, Finns rigida, Finns koraiensis and Finns densiflora by liquid culture, were investigated. Activity of Cellobiohydrolase (CBH) from F. palustris was detected in the every test softwoods culture, showing activities of the Endoglucanase (EG), $\beta$-glucosidase (BGL) and $\beta$-1,4-xylosidase (BXL). It was shown high enzyme activities in the sapwood culture than heartwood of the same wood species, However, the enzyme activities in most of test wood cultures increased with longer incubation time, indicating a possibility of intermix sapwood and heartwood for degradation process by enzyme. Also it was shown that protein patterns of the extracellular enzyme from F. palustris in wood particle substrate of the several domestic softwoods were similar with each other wood species, which suggested the possibility of mixing all softwoods in saccharification by enzyme from F. palustris. Crystallinity reduction value of cellulose by F. palustris was 4.2~20.4% in 4 weeks cultivation, 12.9~28.9% in 8 weeks.

• KSBB Journal
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• v.6 no.2
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• pp.167-174
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• 1991

Enzymatic cellulose hydrolysis depends on the several factors such as the structural features (CrI, particle size and surface area, etc.), the nature of cellulase enzyme system, the inhibitory effects of products, and enzyme deactivation. At the presence of products on the initial hydro- lysis rate of cellulose, cellobiose has more severe inhibitory effect than glucose. Othewise, the inhibition effect of products for adsorbed enzyme is related to the glucose and cellobiose conentration hyperbolically. Enzyme deactivation of FPA and ${\beta}-glucosidase$ were expressed by exponential decay profile.

• Biotechnology and Bioprocess Engineering:BBE
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• v.1 no.1
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• pp.18-21
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• 1996

A continuous production of fructooligosaccharides from sucrose was investigated by fructosyltransferase immobilized on a high porous resin, Diaion HPA25. The optimum pH(5.5) and temperature(55$^{\circ}C$) of the enzyme for activity was unaltered by immobilization, and the immobilized enzyme became less sensitive to the pH change. The optimal operation conditions of the immobilized enzyme column for maximizing the productivity were as follows: 600g/L of sucrose feed concentration, flow rate of superficial space velocity 2.7h-1. When the enzyme column was run at 50$^{\circ}C$, about 8% loss of the initial activity of immobilized enzyme was observed after 30 days of continuous operation, during which high productivity of 1174g/L$.$h was achieved. The kinds of products obtained using the immobilized enzyme were almost the same as those using soluble enzymes or free cells.

• Korean Journal of Pharmacognosy
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• v.17 no.1
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• pp.91-99
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• 1986

The single treatment of mice with steam distillate, non-volatile ether extract and methanol extract from mace (Arils of Myristica fragrans) caused a significant prolongation of hexobarbital-induced narcosis and increase in strychnine toxicity as well as a significant decrease in hepatic microsomal drug metabolizing enzyme activities. On 7 consecutive daily administrations, however, the duration of hypnosis was markedly shortened and significant increases in the hepatic enzyme activities were shown. With systematic fractionation by $SiO_2$ column chromatography of non-volatile ether fraction monitoring by animal tests a new lignan (mp $70{\sim}72^{\circ}$, MW 328, $[{\alpha}]^{20}_D+5.28$) was isolated as an active principle and its structure was elucidated as (2R, 3S)-1-(3,4-methylendioxyphenyl)-2,3 dimethyl-4-(4-hydroxy-3-methoxyphenyl) butane.

• Korean Journal of Pharmacognosy
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• v.17 no.3
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• pp.189-194
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• 1986

The single acute treatment of mice with the steam distillate, non-volatile ether extract and methanol extract from mace, arils of Myristica fragrans(Myristicaceae) caused a significant prolongation of hexobarbital-induced narcosis, an increase in strychnine toxicity as well as a significant decrease in hepatic microsomal drug metabolizing enzyme activities. On seven daily consecutive administrations, however, the duration of narcosis was markedly shortened and significant increases in the hepatic enzyme activities were shown. From the non-volatile ether fraction, macelignan, a new lignan, mp $70{\sim}72^{\circ}$ was isolated as an active principle.

• Archives of Pharmacal Research
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• v.13 no.3
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• pp.265-268
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• 1990

The effects of lignans, related to macelignan, on hepatic microsomal drug-metabolizing enzyme (DME) activity were evaluated to elucidate the structure-activity relationship in mice and rats. The compounds carrying the methylenedioxyphenyl nucleus were found to be the msot potent among compounds tested; which not only produced a marked inhibition of DME with a single dose but a significant induction with repeated treatments. Lack of the methylenedioxy group caused marked decrease in the activity, implying that a methylenedioxy group is essential and of major importance eliciting DME modifying activity.

• Journal of Applied Biological Chemistry
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• v.49 no.4
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• pp.135-139
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• 2006

A alkalophilic strain, Bacillus licheniformis MH31 producing an alkaline protease was isolated from mine soil of Boryeong in Korea. Production of a high level of alkaline protease was achieved 42 h after incubation when the bacterium was grown at pH 9.0 and $35^{\circ}C$ in Horikoshi medium supplemented with 0.5%(w/v) starch and 1%(w/v) skim milk as carbon and nitrogen source, respectively. The molecular weight of partially purified enzyme was estimated to be 30 kDa by SDS-PAGE and its optimum pH was pH 10. The enzyme showed optimum temperature at $50^{\circ}C$, and was stable up to $60^{\circ}C$ after 1 h incubation. The protease was strongly inhibited by 1 mM of PMSF which was known well as strong inhibitor of serine proteases, but almost not inhibited by 5 mM of EDTA and 1,10-phenanthroline. When the protein hydrolysis products of 1% skim milk by partially purified protease was compared with available commercial proteases using HPLC analysis, most of hydrolysis products were detected below molecular weight of 10,000 and the hydrolysis ratio of purified enzyme was 24.8% lower than those(above 32%) of commercial proteases.

• Journal of Microbiology and Biotechnology
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• v.30 no.7
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• pp.1092-1096
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• 2020

YjiC, a glycosyltransferase from Bacillus licheniformis, is a well-known versatile enzyme for glycosylation of diverse substrates. Although a number of O-glycosylated products have been produced using YjiC, no report has been updated for nucleophilic N-, S-, and C- glycosylation. Here, we report the additional functional capacity of YjiC for nucleophilic N- and S- glycosylation using a broad substrate spectrum including UDP-α-D-glucose, UDP-N-acetyl glucosamine, UDP-N-acetylgalactosamine, UDP-α-D-glucuronic acid, TDP-α-L-rhamnose, TDP-α-D-viosamine, and GDP-α-L-fucose as donor and various amine and thiol groups containing natural products as acceptor substrates. The results revealed YjiC as a promiscuous enzyme for conjugating diverse sugars at amine and thiol functional groups of small molecules applicable for generating glycofunctionalized chemical diversity libraries. The glycosylated products were analyzed using HPLC and LC/MS and compared with previous reports.

• Biomedical Science Letters
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• v.8 no.1
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• pp.29-37
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• 2002

Listeria monocytogenes poses an increasing health risk, which in part is due to increasing health risk, consumption of ready-to-eat food products and the introduction of increasing numbers of food products from regions with different dietary habits. L. monocytogenes can be present in meat, shellfish, vegetables, unpasteurised milk and soft cheese and poses a risk if food containing these products is stored at refrigeration temperature and is not properly heated before consumption, as L. monocytogenes is psychrophilic. Amplified-fragment length polymorphism (AFLP) analysis is the method of genotypic techinique in which adaptor oligonucleotides are ligated to restriction enzyme fragments and then used as target sites for primers in a PCR amplification. The amplified fragments are electrophoretically separated to give strain-specific band profiles. Single-enzyme approach that did not require costly equipment or reagents for the fingerprinting of strains of Listeria monocytogenes was developed. Single-enzyme amplified fragment length polymorphism (SE-AFLP) analysis was used to perform species and strain identification of Salmonella, Shigella, Yersinia and E. coli. By careful selection of AFLP primers, it was possible to obtain reproducible and sensitive identification to strain level. The AFLP patterns of L. monocytogenes are divided by the kinds of specimens in which were isolated. SE-AFLP fragments can be analyzed using standard gel electrophoresis, and can be easily scored by visual inspection, due to the low complexity of the fingerprint obtained by this method. These features make SE-AFLP suitable for use in either field or laboratory applications.

• Korean Journal of Microbiology
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• v.27 no.1
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• pp.35-42
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• 1989

The mode of transglycosylation reaction observed during the action of low-molecular-weigh $\beta$-D-glucosidase ($\beta$-D-glucoside glucohydrolase, EC3.2.1.21) purified from Trichoderma koningii ATCC 26113 was investigated using $^{1}H$-NMR spectroscopy. The enzyme was purified by the series of procedures including ammonium sulfate precipitation, and fractionations by column chromatographies on Bio-Gel P-150, DEAE-Sephadex A-50, and SP-Sephadex C-50. The final purification was performed by the band eluation after preparative polyacrylamide gel electrophoresis. The enzyme showed its molecular size of 78,000 through the analysis of sodium dodecyl sulfate-polyacrylamide gel electrophoresis and its isoelectric point of 5.80 through the analysis of analytical isoelectric focusing. The H-1 proton resonances were analyzed. After the reaction of the enzyme with cellobiose, the reaction products were separated by high performance liquid chromatography using refractive index detector. H-1 resonances of the products were consisted with those of gentiobiose [$\beta$-D-glucopyranosyl--(1,6)-D-glucopyranose], and cellotriose [$\beta$-D glucopyranosyl-(1,4)-$\beta$-D-glucopyranosyl]-(1,4)-D-glucopyranose] with minor resonances of sophorose [$\beta$-D-glucopyranosyl-(1,2)-D-glucopyranose], respectively.