• KSBB Journal
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• v.17 no.2
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• pp.189-194
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• 2002

Laccase produced from Trametes sp. was immobilized on CNBr-activated Sepharose-4B (CAS4B) and tested for degradation of azo dyes. Laccase was efficiently immobilized on CAS4B. Immobilization of laccase on CAS4B increased pH, thermal and proteolytic stabilities. Optimum pH and temperature of immobilized laccase were pH 3 and 40$\^{C}$, respectively as same as those of free laccase. The K$\_$m/($\mu$mol/ml) values of free and immobilized laccase for Reactive Blue 19 as the substrate were 0.34 and 2.07, respectively V$\_$max/($\mu$mol/mL$.$min) values of them were 0.12 and 0.1, respectively. In repeated batch reactions, conditions retained high stability and degradation of dye for immobilized laccase were pH 5 and 30$\^{C}$. HBT didn\\`t decrease highly activity of immobilized laccase. Immobilized laccase was very stable for degrading dyes continuously in a packed-bed reactor containing laccase immobilized on CAS4B. For continuous degradation of 100 $\mu$M Reactive Blue 19 and 50 $\mu$M Acid Red 57 in the presence of 0.1 mM HBT under optimum conditions, immobilized laccase retained 70% of degradation ability even after 30 hours.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 2001.04a
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• pp.18-25
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• 2001

A new wood-degrading fungus Trichophyton rubrum LKY-7 secretes a high level of laccase in a glucose-peptone liquid medium. The production of laccase by the fungus was barely induced by 2,5-xylidine. The laccase has been purified to homogeneity through three chromatography steps in an overall yield of 40%. The molecular mass of the purified laccase was about 65 kDa by sodium dodecyl sulfate polyacrylamide gel electrophoresis. The purified laccase had the distinct blue color and had basic spectroscopic features of a typical blue laccase: two absorption maxima at 278 and 610 nm and a shoulder at 338 nm. The N-terminus of the laccase has been sequenced, revealing high homology to laccases from wood-degrading white-rot fungi such as Ceriporiopsis subvermispora. The enzyme had a "low" redox potential (0.5 V vs normal hydrogen electrode), yet it was one of the most active laccases in oxidizing a series of representative substrates/mediators. Compared with other fungal laccases, the laccase has a very low Km value with ABTS [2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid] as a substrate and a very high Km value with violuric acid as a substrate. The laccase has the isoelectric point of 4.0. The laccase had very acidic optimal pH values (pH 3-4) while it was more stable at neutral pH than at acidic pH. The laccase oxidized hydroquinone faster than catechol and pyrogallol. The oxidation of tyrosine by the laccase was not detectable under the reaction conditions. The laccase was strongly inhibited by sodium azide and sodium fluoride. fluoride.

• Journal of the Korean Society of Food Science and Nutrition
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• v.25 no.2
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• pp.240-248
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• 1996

To clarify the potentiality of sea cucumbers as dietary food, the effects of those glycoprotein on dietary proteins and physicochemical properties of those proteins were studied. Crude glycoprotein was efficiently extracted using 20mM sodium phosphate beffer(pH 7.0) and by salting out with 80% ammoniym sulfate saturation. The fractions obtained through the DEAE-cellulose ion exchange chromatography was identified as glycoprotein by Schiff's reagent and SDS polyacrylanide gel electro-phoresis. The yields of each glycoprotein from the three kinds of sea cucumbers were 0.814(red), 0.184(blue) and 0.232(black) and the molecular weights of the glycoproteins subunits were ranged from 20,000 dalton(blue and black) to 29,000 dalton(red), respectively. The electrophoretic patterns of the glycoprotein isolates were similar to each other and any significant difference in amino acid pattern was observed. Predominant arnino scids were Asx(aspartic acid and asparagine) and Glx(glutamic acid and glutamine) ; in contrast, histidine and methionine were below 2% as compared to total amino acids. water holding capacities of the glycoprotein isolates from red, blue and black cucumbers were equally 100% and emulsion activities ranged from 53% to 64%. In addition the emulsion stabilities were 7.04, 1.37 and 2.44, respectively. In vitro digestibility of some proteins(casein, SPI and squid) was decreased as increasing the level of the freeze dried sea cucumber powder and glycoprotein isolates. But squid protein was not affected.

• The Korean Journal of Food And Nutrition
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• v.13 no.4
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• pp.383-389
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• 2000

Stabilities to heat, pH, light were investigated about isolated red color pigment from the Korean Lithospermum erythrorhizon. The extracted pigment, acetylshikonin was stable heating at 40∼80$\^{C}$ for 1∼2 hours, hut it was specially unstable on the storage above 55$\^{C}$. The extracted pigment, acetylshikonin was stable on the sunlight under the red and green filters but unstable under the yellow and blue filters. The extracted pigment, acetylshikonin was stable under the pH of 4∼8 but unstable under the pH above 10. The extracted pigment, acetylshikonin was stable under the KCl and NaCl at concentration of 10$\^$-1/Mole. The pigment was very unstable under the CaCl$_2$, FeCl$_3$, CoCl$_2$, AlCl$_3$ and MnCl$_2$ at concentration of 10$\^$-1/Mole. The red pigment, acetylshikonin was stable under citric acid and acetic acid at concentration of 1 Mole. Especially, acetic acid was effective for the stability of the pigment.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.27 no.3
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• pp.259-264
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• 1994

The possibility of shellfish utilization of juice as seasoning materials was examined through the analyzing proximate compositions and N-containing materials. The amounts of the sucking liquid wastes were estimated as 58,819 tons for oyster, 764 tons for pen-shell, 604 tons for cockle and 3,896 tons for blue-mussel from 1985 to 1990 in Korea. Water contents ranged from 95.2 to $97.4\%$ and crude protein level was $1.0{\sim}1.4\%$. Taurine was the most abundant nitrogenous compound($40{\sim}56\%$) in extracts, and glycine($10.4{\sim}36.1\%$), alanine($4.8{\sim}8.6\%$) and glutamic acid($3.1{\sim}5.3\%$) followed. More than $40\%$ of ADP and AMP as mucleotide were contained in all shellfish samples but pen-shell and cockle had $20\%$ of inosine, also. Glycinebetaine was present in corcentrations of 139.8mg/g in oyster and $45.5{\sim}61.9mg/100g$ in pen-shell, cockle and blue-mussel. Total creatinine and trimethylamine oxide levels were $30.4{\sim}59.1mg/100g$ and $0.82{\sim}47.2mg/100g$, respectively.

• Korean Journal of Plant Resources
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• v.29 no.4
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• pp.363-375
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• 2016

Potentilla kleiniana is a perennial herb beloning to Rosaceae family. Herein we investigated the effect of light intensity, light quality and chemical elicitor on plant growth and the accumulation of bioactive compounds in P. kleiniana. After 60 days of cultivation under different shading level [0% (200 μmol·m⁻²·s⁻¹), 35% (95 μmol·m⁻²·s⁻¹), 55% (65 μmol·m⁻²·s⁻¹), 75% (40 μmol·m⁻²·s⁻¹)] in the greenhouse, chlorophyll and carotenoid content were the highest under 35% treatment, however, plant height, leaf number and biomass were the highest under non-shading. As a result of cultivation among strong light condition as a control, florescence and three mixture light sources [red:white:blue (RWB) = 8:1:1, red:blue (RB) = 8:2, red:green:blue (RGB) = 8:1:1] as treatments in plant growth chamber (25 ± 2℃, 185 ± 3 μmol·m⁻²·s⁻¹), growth, biomass, chlorophyll content low difference between total phenolic compouds and flavonoid content were higher under RWB treatment. DPPH radical elimination ability was the highest under all treatments especially florescence and RGB treatment except control. As a result of treating chemical elicitor [salicylic acid (SA), methyl jasmonate (MeJA)] concentration (0, 50, 100, 200 μM) respectively, plant height, petiole diameter and biomass were higher under non-treatment, MeJA 50 μM. It was investigated that fresh weight and dry weight under MeJA 50 μM treatment were especially a little high. Total phenolic compounds and flavonoid content of SA 50 μM treatment was the highest but DPPH radical elimination ability was significantly the highest under MeJA 200 μM (88.65%) and MeJA 50 μM (87.84%) treatment. Thus, this study suggested that we determined optimal shading and light quality in the greenhouse and plant growth chamber also confirmed bioactive compound content, antioxidant ratio increase according to different chemical elicitation concentration.

• Journal of the korean academy of Pediatric Dentistry
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• v.35 no.2
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• pp.216-224
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• 2008

The purpose of this study was to evaluate the effectiveness of fissurotomy and double application time of acidic primer of self-etching adhesive system of acid treatment on enamel surfaces for prevention of microleakage of pit and fissure sealants. The microleakage of pit and fissure sealants was evaluated by measuring the penetration depth of methylene blue solution. Specimens were divided by 4 groups according to the method of treatment. Group I: 35% phosphoric acid etching, 20 seconds. Group II: Priming with self-etching primer, 20 seconds. Group III: Priming with self-etching primer, 40 seconds. Group IV: Priming with self-etching primer, 20 seconds, after fissurotomy. The etched pattern produced on enamel was observed using a scanning electron microscope. Obtained data were analysed statistically using Kruscal-Wallis test followed by Mann-Whitney test for comparison of groups. The results are as follows: 1. Microleakage scores of group IV priming with self-etching primer 20 seconds after fissurotomy was the lowest. 2. Microleakage scores between group II and group III were not shown significant difference. 3. Enamel for 20 seconds etching with 35% phosphoric acid was observed the most effective etching pattern. And the etching pattern on the fissure enamel with self-etching adhesive 20 seconds after fissurotomy was more prominent than group II, III only using self-etching primer.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 2003.11a
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• pp.1-8
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• 2003

변색목재의 화학적 성질을 조사한 결과, 처리전.후의 유기용매추출물 함량에 있어서 소나무재 및 리기다소나무재 공히 노화 및 변색균처리포 그 함량이 낮아지는 결과를 나타냈는바, fatty acids와 sterols 은 3주간 노화처리로 10.6-11.2%, 변색균처리로 36-41.1%의 높은 감소율을 나타냈다. triglycerides도 3주간 노화처리로 5.68-9.4%, 변색균처리로 38.5-40.0% 높은 감소율을 나타냈다. resin acids의 경우 3주간 노화처리로 6.1-11.3%, 변색균처리로 36-41.5%의 감소율을 나타냈다. 변색목재의 펄프화와 관련하여 소나무재 및 리기다소나무재의 크라프트펄프화결과, 알칼리펄프화에 비하여 펄프수율이 2-3% 높아졌다. 최적펄프화조건으로 활성알칼리농도 20%에서 펄프수율이 46.9-47.8%, reject율이 3.21-3.52%로 낮았다. 변색균처리한 목재도 활성알칼리 20%에서 펄프수율이 비교적 높은 43.5-45%를, reject율이 1.3-1.45%로서 변색균처리 모두에서 현저히 낮아짐을 알 수 있었다.

• Bulletin of the Korean Chemical Society
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• v.35 no.6
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• pp.1809-1816
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• 2014

This study demonstrates gel-to-fluid transition temperatures of polydiacetylene bilayer vesicles could play important roles in their colorimetric transition temperatures. We prepared five types of polydiaceylene vesicles with 10,12-pentacosadiynoic acid (PCDA) and cholesterol (0-40 mol % of total content). From temperature-dependent observations of the optical signals (colors and UV-vis spectra), the blue-to-red colorimetric transition temperatures of polydiacetylene vesicles were decreased with the cholesterol contents. A further study with microcalorimetry and dynamic light scattering revealed that the polydiacetylene vesicles first underwent gel-to-fluid transitions, which were followed by event(s) responsible for the colorimetric transitions. Energies required for each event were quantified from analysis of the peaks in the microcalorimetry thermograms. The inclusion of cholesterol in the vesicles decreased both the gel-to-fluid and the colorimetric transition temperatures, suggesting that the colorimetric transition of the polydiacetylene vesicles was mediated by the former event although the event was not the direct reason for the color change.

• Natural Product Sciences
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• v.10 no.2
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• pp.74-79
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• 2004

Dietary flavonoids are currently receiving considerable attention in developing novel cancer-preventive approaches because of their potential capacities to actively induce apoptosis of cancer cells. In our previous report, a flavonoid fraction, which consisted mainly of protocatechuic acid, fustin, fisetin, sulfuretin, and butein and named RCMF (RVS chloroform-methanol fraction), was prepared from a crude acetone extract of Rhus verniciflua Stokes (RVS) that is traditionally used as food additive and herbal medicine. In this study, we evaluated the effects of the RCMF on cell proliferation and apoptosis using SV40-transformed tumorigenic hepatocytes, BNL SV A.8. Tritium uptake assay showing the proliferative capacity of the cells was strongly suppressed in the presence of RCMF. This anti-proliferative effect was further confirmed through trypan blue exclusion. RCMF-mediated suppression of cell growth was verified to be apoptotic, based on the increase in DNA fragmentation, low fluorescence intensity in nuclei after propidium iodide staining, and the appearance of DNA laddering. Collectively, this study demonstrated that RCMF can be approached as a potential agent that is capable of significantly inhibiting cell growth of hepatic cancer cells.