• Korean Journal of Soil Science and Fertilizer
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• v.21 no.1
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• pp.61-71
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• 1988

This study was conducted to find out the effect of herbicides on soil micro-organism and soil enzyme in loam soil, and on pathogenic microorganism in continuous pepper cropping soil. The result was summarized as follows: When herbicides were treated, the number of soil microorganism generally decreased at the early stage of incubation, and gradually increased at 30 days incubation. The number of fungi was significantly decreased seven times comparison with control plot. The number of actinomycetes was increased at 20 days incubation and that of pytium was increased for all days incubation in Linuron treatment plot. Although the activity of soil enzyme tended to decrease when herbicides were treated, the activities of urease and phosphatase were higher than that of control plot at the early stage of incubation in MO, Linuron and Simetryne treatment plot. In Simetryne treatment plot, the activity of protease was increased at the early stage, and suddenly decreased after 30 days incubation. There was no significant effect of herbicides on the activities of ${\beta}$-glucosidase and polygalacturonase. The activity of cellulase was inhibited at the early stage of incubation, but that of cellulase was higher than that of control plot after 20 days incubation. High significance was showed the correlation coefficient between soil microorganisms except fungi and soil respiration as herbicides were treated, and the total microorganism and soil respiration in Linuron plot. when Dicamba and Simetryne were treated, the correlation coefficient between the total microorganism and the activities of protease and urease were considerably significant.

• Korean Journal of Soil Science and Fertilizer
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• v.29 no.2
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• pp.173-180
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• 1996

Effects of inoculation with phosphate-solubilizing microorganisms, Pseudomonas putida and Aspergillus niger, were studied in both acidic red-yellow and alkaline calcareous soils cropped with pimiento. In red-yellow soil after cultivation, the amounts of soil available phosphorus on non-fertilizer and fertilizer plots inoculated with Aspergillus niger, and on rice straw plot inoculated with Pseudomonas putida and Aspergillus niger were significantly higher than uninoculation treatments, but there were no differences in calcareous soil. With inoculation of either Pseudomonas putida or Aspergillus niger, increase in phosphorous uptake by pimiento cultivated in calcareous soil was detected on non-fertilizer, and fertilizer plots except rice straw plot. Although there were no significant differences in soil cellulase activities among treatments, the activity was the highest on rice straw plot in red-yellow soil. The phosphatase activities in red-yellow soil were increased by the inoculation with Aspergillus niger only, and the activity in calcareous soil was improved by the inoculation with either Pseudomonas putida or Aspergillus niger.

• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.11
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• pp.1482-1485
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• 2007

In this study, extraction yield of ginseng and contents of phenolic compounds were increased through enzyme and heat treatment, and antioxidant activities of each treatment group were investigated. In the case of enzyme treatment groups, the extraction yields showed remarkable difference: pectinase (76.0%)> cellulase (44.7%)> ${\alpha}-amylase$ (43.1%)> protease (34.3%). Heat treatment groups did not show much difference in extraction yields $(51.1{\sim}53.1%)$ except for $90^{\circ}C-treated$ group (48.7%). Pectinase-treated group (2.21%) and $90^{\circ}C$ heat treatment group (2.34%) showed the highest total phenol contents. DPPH radical scavenging activities of the solvent-treated, enzyme-treated and heat-treated extracts were $12.3{\sim}33.2%$, $29.7{\sim}40.3%$ and $57.8{\sim}75.2%$, respectively, at 100 mg/mL concentration. The pectinase-treated extract exhibited the greatest ABTS radical scavenging activity (60%), followed by $150^{\circ}C$, $ 120^{\circ}C$, and $90^{\circ}C-treated$ groups.

• Korean Journal of Food Science and Technology
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• v.37 no.3
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• pp.504-507
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• 2005

Trichoderma reesei KCTC 6952 possesses cellulase system consisting of three enzymatic components necessary to synergistically hydrolyze crystalline cellulose, among which ${\beta}$-glucosidase effectively releases glucose from glycoside derivatives. ${\beta}$-Glucosidase of T. reesei KCTC 6952 grown in modified Mandels' medium showed maximum activity(1.33 unit/mL) 4 days after initiation of growth. Optimal reaction conditions of the enzyme were 50 mM sodium acetate (pH 5) at $70^{\circ}C$ for 10 min. Enzymatic activities stabilized below $50^{\circ}C$ at pH range of 4-5. Results show ${\beta}$-glucosidase exerted its catalytic activities at relatively high temperatures and broad pH range.

• Journal of Sericultural and Entomological Science
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• v.51 no.2
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• pp.164-172
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• 2013

This study was carried out to investigate functional quality characteristics of extract obtained after sugar-leaching for 12 weeks (SLE) and extract obtained after lactic acid fermentation for 8 weeks (LFE) of mulberry leaves. The yield, sugar content, pH, and total acidity of SLE were 27%, 43 $^{\circ}Brix$, 4.6, and 0.45%. The yield, sugar content, pH, and total acidity of LFE were 166%, 33 $^{\circ}Brix$, 3.6, and 1.17% respectively. The lactic acid bacteria viable numbers ($1.2{\times}10^{10}$ CFU/ml) of LFE were more than those of SLE ($2.8{\times}10^2$ CFU/ml). The LFE expressed activities of hydrolytic enzymes (amylase, cellulase, pectinase, protease), but SLE did not express. The contents of acetic acid, citric acid, and malic acid of SLE were higher than those of LFE, but lactic acid content of LFE was higher than that of SLE. The main free sugars of SLE were glucose (200.93 mg/g), fructose (236.32 mg/g), and sucrose (18.41 mg/g), but LFE did not detect all free sugars. The contents of polyphenol, anthocyanin, and piperidine alkaloid of LFE were higher than those of SLE. ${\alpha}$-Glycosidase activities were inhibited 3.4% and 16.2% by SLE and LFE. These results suggest that lactic acid fermentation extraction is an effective method to increase the yield and contents of functional quality of mulberry leaves extract.

• Korean Chemical Engineering Research
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• v.49 no.1
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• pp.101-104
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• 2011

Cellobiose dehydrogenase(CDH) as a hemoflavoenzyme is secreted out of cell in the cellulose degradation. As CDH strongly bound to amorphous cellulose, it helps cellulose hydrolysis by cellulase. CDH may have an important role of saccharification process for bioethanol production. In this study, Phanerochaete chrysosporium ATCC 32629 was selected for the production of CDH among other strains tested. The optimal temperature and pH of CDH produced by P. chrysosporium ATCC 32629 were ${55^{\circ}C}$ and 4, respectively. To improve the activity of CDH, the mutation of P. chrysosporium was performed using proton beam that has high energy level partially. As a result, P. chrysosporium mutant with the high activity was selected at 1.2 kGy in a range of 99.9% lethal rate. The CDH and $\beta$-glucosidase activities of mutant were 1.4 fold and 20 fold higher than those of wild strain. Therefore, P. chrysosporium mutant with the high activities of CDH and $\beta$-glucosidase was obtained from mutation by proton beam irradiation.

• Applied Biological Chemistry
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• v.50 no.2
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• pp.87-94
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• 2007

A bacterium which has high enzymatic activities such as amylase, cellulase and protease was isolated from Korean traditional soybean food, doenjang. The isolated bacterium was identified to Bacillus subtilis HS25 by the test of morphological and biochemical properties according to Bergey's Manual of Systematic Bacteriology and API 50 CHL kit, and by the 16S rDNA sequence. The isolated B. subtilis HS25 had a potent antibacterial activity against food born causative or pathogenic bacteria. B. subtilis HS25 is endospore forming cell and contained flagella and abundant viscous material at the out layer of cell wall. It was rod type bacterium $(0.5{\sim}0.8{\times}3{\sim}5{\mu}m)$ having biochemical characteristics such as gram staining(+), catalase(+), oxidase(-) and hydrolysis of esculin(+). The optimal medium compositions for production of antibacterial substance in the B. subtilis HS25 were 1% of soluble starch, 0.5% of yeast extract, 0.5% of peptone and 0.05% of MgCl$_2{\cdot}6H_{2}O$. The optimum temperature and pH of the growth of the B. subtilis HS25 was 35$^{\circ}C$ and pH 7.5, respectively. The antibacterial activity was more high in neutral to a little alkaline pH (6.5-10.5) than in acidic pH. The optimal shaking speed to grow and to produce antibacterial substance of the B. subtilis HS25 was 160${\sim}$200 rpm. The optimal culture time for antibacterial activities of the bacterium were shown to be in the range of 12-36 hr.

• Microbiology and Biotechnology Letters
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• v.35 no.3
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• pp.255-260
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• 2007

This study was conducted to isolate and identify bacteria producing xylanase and cellulase from spent mushroom substrates and to determine the optimal medium conditions for their growth. Bacteria showing high xylanase and carboxymethyl cellulase activities and low protease and amylase activities were strain 201-3 and strain 206-3. Strain 201-3 was identified as Enterobacter ludwigii and named Ent. ludwigii KU201-3. 206-3 was identified as Bacillus cereus and named B. cereus KU206-3. The optimal medium condition of Ent. ludwigii KU201-3 was obtained when 1%(w/v) of soybean meal and 3%(w/v) of sucrose were used as nitrogen and carbon source, respectively. That of B. cereus KU206-3 was obtained when 3%(w/v) of soybean meal and 1%(w/v) of molasses were used as nitrogen and carbon sources, respectively.

• The Korean Journal of Mycology
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• v.46 no.2
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• pp.145-160
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• 2018

Members of Chlorociboria are soft-rot ascomycetes that produce blue-green pigment. We investigated the growth characteristics of two Korean species of Chlorociboria, eight strains of Chlorociboria aeruginascens and Chlorociboria poutoensis, under various culture conditions (solid media, temperature, pH) and screened them for extracellular enzyme activity. Although the growth rate was slow, all tested strains of Chlorociboria spp. grew well on potato dextrose agar (PDA; 16.3~42.6 mm after 60 days) or Sabouraud dextrose agar (SDA), but not on malt extract agar (MEA). Compared with C. aeruginascens strains, C. poutoensis strains exhibited higher expression of blue-green pigments on both PDA and SDA media. The optimal temperature for mycelial growth was $20{\sim}25^{\circ}C$, and mycelial growth was lower at $30^{\circ}C$ than at $10^{\circ}C$. All strains tended to have increased mycelial growth as the incubation temperature increased in the range of 10 to $20^{\circ}C$. The optimal pH of potato dextrose broth (PDB) for mycelial growth varied according to the strain under static culture conditions. Maximum biomass production was obtained at pH 6.0 for NIFoS 579 ($114.3{\pm}5.1mg/60days$), but it maintained a stable pigment expression under a broad pH spectrum. The activities of both cellulase and laccase were observed in all tested strains of Chlorociboria spp. Enzyme activities of NIFoS 579 were remarkably higher than those of the other strains. From these results, we suggest that C. poutoensis NIFoS 579 is a potential candidate for use as a source of natural blue-green dye.

• Korean Journal of Food Science and Technology
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• v.51 no.3
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• pp.286-294
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• 2019

The purpose of this study was to investigate the possibility of enhancing the functional compounds in apple and pear pomace (APP) by fermentation with mycelia from the mushroom Lentinula edodes. A 30% (w/v) APP with added rice bran and Biji was fermented with L. edodes at $24^{\circ}C$ and 80% humidity. The cellulase and pectinase activities in the fermented APP (FAPP) were higher than those in the non-fermented control. In addition, the physiological activities of the FAPP, including DPPH, ABTS radical scavenging, and SOD-like activity, as well as the total polyphenol and ${\beta}-glucan$ contents were higher than those in the control. FAPP treatment significantly reduced LPS-induced nitric oxide (NO) levels in Raw 264.7 cell. Therefore, FAPP treatment was considered to more effectively suppress cell injury caused by inflammatory cytokines through inhibition of LPS-induced NO production. These results suggest that the levels of functional components in APP can be increased by fermentation with this mushroom mycelium. However, further studies are needed before it can be used as a functional material.