• BMB Reports
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• 제36권2호
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• pp.167-172
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• 2003

The kinetics of thermal inactivation of copper-containing amine oxidase from lentil seedlings were studied in a 100 mM potassium phosphate buffer, pH 7, using putrescine as the substrate. The temperature range was between $47-60^{\circ}C$. The thermal inactivation curves were not linear at 52 and $57^{\circ}C$; three linear phases were shown. The first phase gave some information about the number of dimeric forms of the enzyme that were induced by the higher temperatures using the "conformational lock" pertaining theory to oligomeric enzyme. The "conformational lock" caused two additional dimeric forms of the enzyme when the temperature increased to $57^{\circ}C$. The second and third phases were interpreted according to a dissociative thermal inactivation model. These phases showed that lentil amine oxidase was reversibly-dissociated before the irreversible thermal inactivation. Although lentil amine oxidase is not a thermostable enzyme, its dimeric structure can form "conformational lock," conferring a structural tolerance to the enzyme against heat stress.

• Journal of Ginseng Research
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• 제9권1호
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• pp.15-23
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• 1985

The study was carried out to confirm the changes of soil physico-chemical properties and population of Fusarium solani by soil managements at preplanning fields for ginseng cultivation. Soil porosity and aggregation had been significantly increased during the managements while exchangeable nitrogen content and bulk density of the soil had been decreased. Available phosphate and exchangeable potassium content, in addition, seemed to be slightly increased. And soil aggregation showed positive correlation with clay, organic matter, soil moisture, and Ca content in the soil but negative with K content. Decrease rate of NH4-N and NO3-N content after soil managements were 55% and 41% in average, respectively. And better decrease effect for NH4-N was obtained in sand loam soil whereas no effect for NO3-N with soil textures. The more ploughing seemed to result in less propagules of F solani in the soil, however there was non significant decrease in population of the pathogen after the soil management. Number of F. solani in soil was significantly less in the fields where gramineous and leguminous crops had been grown as a precrop than other crops tested. Meanwhile there was no correlation between soil texture and population of the pathogen in the soil.

• Journal of Plant Biology
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• 제34권4호
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• pp.289-296
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• 1991

Cultures of hairy root induced from ginseng(Panax C.A. Meyer) transformed with Agrobacterium rhizogenes (strain A4, ATCC 15834) were established and morphologically two different hairy root strains (HB1, HB2) were obtained. To determine the optimum growth rate, the hairy root (HB2) was cultured in various liquid medium supplemented with or without plant growth hormone. The growth rate of hairy root cultured on MS medium was 1.3-3.1 times higher than those cultured on other media, and the optimum sucrose concentration and pH were 3-6%, 5.5-6.5, respectively. Also, the growth rate of hairy root was increased when 0.02 M ammonium nitrate, 1.2 mM potassium phosphate (monobasic) and 0.5 mg/l IBA were supplied to liquid medium. The saponin patterns and contents of hairy root (HB2) were determined by TLC and HPLC. The crude saponin contents were 4.67% and the total saponin contents were 1.0%, on dry weight basis.

• 한국세라믹학회지
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• 제42권5호
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• pp.338-345
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• 2005

To prepare the complex gel of flux and pseudo-boehmite used in precursor of the flaky ${\alpha}-A1_2O_3$ crystal, aqueous solution of the mixture of sodium carbonate and sodium phosphate was added with stirring in aqueous solution of the mixture of sodium sulfate, potassium sulfate and titanium sulfate. The complex gel was dried at $110^{\circ}C$ and was crystallized above $1,050^{\circ}C$, and then the effect of the amount of titanium sulfate on size, morphology, thickness and crystal size distribution of the flaky ${\alpha}-A1_2O_3$ crystal was investigated. Addition of titanium sulfate was prevented the aggregation and generation of twin crystal, and had an effect on the crystal size and the thickness during crystal growth. When the amount of titanium sulfate was more than 6 g, particle size was decreased but was free from crystal twining and aggregation. On the other hand, when the amount of titanium sulfate was lower than 6 g, crystal size was increased but crystal twinning and aggregation were noticed.

• Journal of Nutrition and Health
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• 제32권1호
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• pp.90-100
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• 1999

In order to investigate dietary risk factors for hypertension in th elderly, dietary intakes and dietary habits of 405 elderly subjects, aged 60-94, were assessed by the questionnaire, anthropometric measurement and a 24-hour dietary recall. The prevalence of definite (>95mmHg for diastolic or>160mmHg for systeolic blood pressue) and borderline(90-95mmHg for diastolic or 140-160mmHg for systolic blood pressure) hypertensive subjects 33.3% and 19.3%, respectively. The distribution of the subjects for Body Mass Index(BMI), waist-hip ratio, and alcohol consumption were significantly different among definite, borderline, and normal groups(p<0.05). The distribution of the subjects for smoking, exercise, and preference of salty food were not significantly different among definite, borderline, and normal groups(p>0.05). From the generalized logistic regression analysis of the risk factors for the hypertension, the subjects with over 27 of BMI had significantly higher risk of hypertension. Alcohol consumption and preference of salty food were significant risk factors of hypertension in the elderly. Dietary risk factors for the hypertension that had significant relationship to the hypertension were intakes of potassium, calcium, phosphate, sodium, vitamin B1, niacin, and folate. There was no significant difference of consumption frequencies of food and dish among definite, borderline, and normal groups(p>0.05). The amount of intakes for cereals and grain product, bean and their products, eggs were significantly different among definite, borderline, and normal groups(p<0.05). In summary, the amount of dietary intakes to hypertension in elderly population. Longitudinal studies for dietary risk factors on incidence of hypertension are needed in general population, especially in the elderly.

• 한국미생물·생명공학회지
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• 제22권6호
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• pp.665-671
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• 1994

For the production of pyrogallot from gallic acid, about 100 strains of bacteria capable of assimilating gallic acid as a sole carbon and energy source were isolated from the soil. JH- 004 strain showing the highest activity of gallate decarboxy#lase was selected from them and identi- fied as Erwinia sp. The optimal conditions for the production of pyrogallol from gallic acid were examined. The resting cells of JH-004 cultured in a complex medium containing 0.2%(w/v) gallic acid were prepared after the treatment of the pellet with a freezing and thawing, and used as a enzyme source. The reaction mixtures for the maximal production of pyrogallol were shown to be 6 g/l of resting cells and 15 g/l of gallic acid in 25 mM potassium phosphate buffer. The optimal pH for the reaction was 5.0 and the optimal temperature was 35$\circ$C . Additionally, Triton X-100(0.01%, w/v) was found to be most effective for the production of pyrogallol. Under the above conditions, 10.27 g/l of pyrogallol was produced from 15 g/l of gallic acid after incubation of 35 hrs. This amount of pyrogallol corresponds to a 92.37% yields, based on gallic acid.

• 한국식품위생안전성학회지
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• 제2권2호
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• pp.67-73
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• 1987

Kluyveromyces fragilis로부터 $\beta$-galactosidase의 생성조건과 조효소액의 성질 그리고 당 전이 반응에 의한 oligosaccharide 생성을 조사한 결과 다음과 같은 결과를 얻었다. \circled1 Peptone-Yeast extract 배지에 6% lactose를 첨가하였을 때 최대 효소생산을 보였다. \circled2 0.05 M potassium phosphate buffer (pH 7.0)에서 3% toluene를 첨가하여 37$^{\circ}C$ 5시간 배양하였을 때 K. fragilis로부터 효소가 최대로 추출되었다. \circled3 효소의 최적온도는 4$0^{\circ}C$이고 4$0^{\circ}C$ 이상의 열처리에서는 효소가 파괴되었으며, pH6-7에서는 상당히 안정하였다. \circled4 ONPG 기질로 사용하였을 때 Km 값은 2.5mM이었다. \circled5 당 전이 반응의 결과, 7개의 oligosaccharide가 생성되었다. 이상의 실험결과로 볼 때, 본 실험에 사용한 K. fragilis SKD 7001은 Beta-galactosidase의 생산을 위해서 이용 가치가 인정되었으며, 특히, 이 효소의 활성이 중성 pH에서 강하고 안정한 상태를 보이는 것은 시유나 원료우유의 lactose를 중성에서 해야 한다는 점을 고려할 때, 실용적 가치가 있다고 본다. 또, 이 효소의 작용과정에서 생성되는 oligosacchride는 장내 bifidus균의 생육을 촉진시키는 효과가 인정되고 있기 때문에 이용가치를 더욱 높여주는 것으로 생각된다.

• 한국작물학회지
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• 제36권3호
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• pp.259-265
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• 1991

시비법과 생장조정제등의 여러가지 재배방법을 강구하여 참깨의 단경화와 수량성의 변화를 구명하였던 결과를 요약하면 다응과 같다. 1. 단경화의 효과적인 방법은 참깨의 출현후50일에 적심함으로서 10cm의 주경단축을 가져왔고 그 다음으로 B-9생장조정제의 엽면살포가 8cm, 다찌가랜 엽면살포가 6cm의 단경화에 기대되는 방법이었다. 2. 종실수량에 관여한 수량구성요소들은 주당삭수 주당입수, 상단부위 및 중단부위 삭내 등숙율 등 이었고 특히 상단부위의 삭내 등숙율은 종실수량과 밀접한 관계가 있었다. 3. 퇴비의 증시는 단경화의 효과는 없었으나 주당삭수, 주당입수 및 상단부위 삭내 등숙율을 향상시켜 12%의 증수효과를 가져왔다 4. 다찌가랜의 엽면산포는 6cm의 단경화는 물른 주당삭수, 주당입수 및 상단부위의 삭내 등숙율의 향상에 의한 8%의 증수효과를 가져 왔으며 특히 건근중비를 높여 도복에 의한 근의 발취현상이 최소화될 것으로 기대된다.

• Plant Resources
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• 제6권2호
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• pp.102-107
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• 2003

To find out the optimum fertilizer level for high yielding variety, Velox, experiment was conducted with 15 compositions of fertilizer levels at the experiment field of forage crop in Sunchon National University from Mar. 2000 to Aug. 2000. The effects of nitrogen fertilizer on plant growth were significant but increasing rate of application in potassium and phosphate fertilizers above 6 kg/a had negligible effects on plant growth. The optimum nitrogen application level of fertilizers turned out to be 16-6-6 kg/l0a of N-P$_2$O$_{5}$-K$_{5}$O. Content of crude protein was highest and that of crude fiber such as NDF, ADF, cellulose and lignin were lowest at this rate of fertilizer application. Furthermore, IVDMD was high and dry matter yield were highest at the optimum raterate

• 한국축산식품학회:학술대회논문집
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• 한국축산식품학회 2004년도 정기총회 및 제33차 춘계 학술대회
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• pp.198-201
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• 2004

To investigate hydrostatic pressure (HP) effect on myofibrillar protein (Mf) extracted from bovine Semitendinosus muscle, Ca- and Mg-ATPase activities to evaluate denaturation of myosin and actin, and soluble protein contents were observed. In Mf treated with 100 MPa for 5 min was not observed denaturation of myosin and actin. In Mf treated with 200 MPa for 5 min, denaturation of myosin and actin were observed but inactivation rate was low (0.0136 $min^{-1}$). Inactivation rate of myosin and actin was dramatically increased above 300 MPa treatment. However denaturation of myosin and actin was not that critical with duration time. By increasing pressure size, the amount of myosin and actin in soluble protein eluted in 20 mM potassium phosphate buffer (pH 7.0) containing 0.6 M NaCl were decreased. SDS-PAGE of soluble protein released from Mf suspension in 0.1 M NaCl buffer (pH 7.0) showed that low molecular weight proteins (15${\sim}$36 KDa) were released by HP treatment above 200 MPa. From the results, denaturation of myosin and actin, and release of light molecule proteins of Mf were observed by HP treatment over 200 MPa.