• Proceedings of the Korean Society of Life Science Conference
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• 2002.05a
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• pp.17-22
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• 2002

지구상에는 수천종의 버섯류가 자생하고 있어 유전자원으로서의 중요성이 지대할 뿐만 아니라 기능성 식품소재 및 각종 약리 활성을 나타내는 신약개발 소재로도 크게 주목을 받고 있다. 이들 버섯은 균사체의 영양대사로 얻어지는 대사산물이 축적된 자실체의 형태로 나타나는데, 최근에 와서 자실체 및 균사체의 추출물이나 균사체 배양물이 체질개선이나 각종 병의 예방과 치료에 효과가 있는 것으로 밝혀져 건강식품이나 의약품으로서의 용도가 크게 증가하고 있는 실정이다. 특히, 담자균이 생산하는 특정 구조를 갖는 다당류는 오래전부터 종래의 화학요법제와는 달리 숙주내의 면역 기능을 부활하여 소위 면역요법제로서의 항암효과를 나타냄이 알려져왔었다. 현재까지 제약 및 의학적인 방법이 질병의 주된 치료방법으로 이용되어 왔지만 최근에 특정식품의 섭취가 만성질환의 발생을 억제 또는 지연시킨다는 연구 보고가 나오면서부터 만성질환의 치료방법으로서 식이요법을 중요하게 생각하게 되었다. 따라서 새로운 식품소재 및 가공식품의 개발을 통한 성인병 등의 각종 질병예방이 국민보건문제 해결에 필수적이다. 현재 일본 등에서는 표고버섯, 구름버섯 및 치마버섯 유래의 다당체 또는 단백다당체인 lentinan, krestin 또는 PS-K, schizophyllan 및 PSP 등이 실용화되어 높은 가격에 판매되고 있다. 국내에서도 야생 구름버섯 자실체로부터 추출한 단백 다당체인 Copolang(광동제약)이 개발되어 PS-K와 유사하게 암의 치료에 병행 사용되고 있고, 또 강력한 항암활성이 보고된 상황버섯의 균사체 추출물인 단백 다당체가 Mesima-Ex FK(한국신약)라는 상품명으로 암의 치료에 병행 사용되고 있는 것으로 알려지고 있다. 담자균류와 아울러 미생물 유래 다당체는 그 구조와 특성에 있어서 매우 다양함을 지니고 있다. 이러한 미생물 유래 다당류의 공업적 생산과 이용에 대한 연구로서는 Leuconostoc mesenteroides가 생산하는 dextran이 혈장증량제로 개발된 이래 Xanthomonas campestris가 생산하는 pullulan, Zoogloea rgmigera가 생산하는zooglan둥이 대표적인 예로 보고되고 있다. 한편, 미생물 유래 다당류는 구성당, 분자량, 화학적 구조 등과 같은 특성의 차이에 의해 많은 종류가 존재하고 있으며, 다양한 물성 및 유화제, 응고제, gel 형성제, 필름 형성제, 흡착제, 안정제, 접착제 등과 같은 용도로 광범위하게 이용되고 있다. 또한 근래에 들어서는 미생물 유래 다당체가 지니는 항암활성이 확인되어 새로운 의약품으로서의 개발 가능성이 기대된다. 그 밖에도 기존에 알려져 있는 식물 및 해조류 유래의 다당체와는 달리, 발효조를 이용한 연속배양에 의해 공업적 대량 생산이 가능하며, 더욱이 생산된 다당체의 분리 및 회수가 용이하다는 이점을 지니고 있다. 최근에 들어서는 유전공학적 기법을이용한 고생산성 변이균주 및 새로운 기능을 지닌 다당체의 개발에 관한 연구가 보고되고 있는 등 고부가가치를 지닌 새로운 바이오 소재로서의 기능 및 용도 개발에 관한 연구가 활발히 진행되고 있다. 이러한 항암 활성을 나타내는 여러 가지 담자균류중 Agaricus blazei로부터 생산되는 다당체는 고형암 이외에 S형 결장암, 난소암, 유방암, 폐암, 간암 등에 효과가 입증되었고, 천연물질에 의한 암 면역요법으로 각광을 받고 있으며, 항암 및 항virus의 완치율과 저지율에서 현재 여러가지 약효가 있는 버섯중에서도 탁원한 효과가 있는 것으로 증명되고 있다. 이들 다당체는 사이토카인을 생산시켜서 T임파구와 B임파구의 항원 특이적인 면역반응을 활성화시키고, 세포장해성 T세포와 활성화 대식세포의 세포장해 기능을 충진시켜서 암세포를 파괴시킨다. 또한 콜로니 자극인자인 사이토카인을 생산시켜서 면역담당세포의 신생을 촉진시키기도 하며, 암의 화학요법과 방사선 요법으로 저하된 백혈구를 회복시키는 역할을 한다. 따라서 최근의 연구동향은 생산된 다당체의 항암활성을 향상시키고자 하여 배양기간중에 interleukin을 의도적으로 첨가하는 경향이 있다. 이러한 항암 활성을 나타내는 담자균체 유래 다당체는 버섯의 기원에 따라 그 형태에 약간의 차이를 나타내기는 하나 그 기본 형태는 ${\beta}-(1,6)-glucosyl$ 분지를 가진 ${\beta}-(1,3)-glucan$이며, 평균 분자량은 50 ${\sim}$ 200만 정도이다. Agaricus blazei의 원산지인 브라질의 피에다데(Piedade) 지방의 환경조건(산지의 습도는 80%, 낮 기온 $35^{\circ)C$, 밤 기온 $20{\sim}25^{\circ}C$로 대단히 높으며, 정기적으로 열대지방 특유의 소나기가 내리는 지역)에서 볼 수 있듯이 Agaricus blazei의 성장 환경은 매우 까다로운 편이며, 날것으로는 보관이 잘 안되기 때문에 그 재배에 큰 어려움이 있다. 또한, 고체배양에 의해 생산된 버섯 자실체로부터 유기용매 및 열수추출 방법으로 다당체를 생산하는 방법은 균일한 형태의 버섯 자실체를 공급받기가 어렵기 때문에 다당체의 생산 수율이 낮고, 많은 노동력이 요구되는 어려움이 있다. 그러나 액체배양에 의한 다당체 생산의 경우는 고체배양에 의한 다당체 생산에 비해 일정한 조건하에서 배양이 가능하다는 장점이 있으며, 항상 균일한 균사체 및 배양액을 얻을 수 있다. 따라서 원하는 유용물질을 쉽게 획득할 수 있는 장점이 있다.

• Korean Journal of Agricultural Science
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• v.7 no.2
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• pp.190-201
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• 1980

This experiment was designed to optimize the process of manufacturing the soybean cheeses and to elucidate the chemical changes during ripening when the chemical changes during ripening when the milk components and enzyme preparations were added to the raw materials. Conditions for extracting soybean protein such as temperature, duration and amount of water added were determined; various coagulaters were compared by checking the curd texture and yield; starters from S. thermophilus, S. lactis MLB and S. cremoris EB-9 were tested as single- or multi-stain combinations; and the effects of skim milk and/or rennins-both microbial and calf origin-addition upon the process of manufacturing and ripening were studied. The results obtained were as follows. 1. optimal conditions for soybean extraction were found to be: temperature $100^{\circ}C$, duration 10 minutes, and amount of water added 9-fold, as considered the extraction rate of solids and proteins, and curd yield. 2. Sodium gluconate was the most effective among the coagulators tested, and 5% of single-strain starter from S. thermophilus was appered to be adequate inoculum for curd formation. 3. The effects of skim milk and/or rennins addition on the process of manufacturing and ripening of soybean cheeses were: 1) The addition of rennins resulted in fast formation of curd, especially with skim milk it was so. And Hansen rennet extracts brought better results in curd formation than Meito rennet extracts did. 2) No significant effect was observed on the changes in moisture content during ripening, however the levels of moisture contents in the products were higher in case of using Meito rennet extracts. 3) Effect on pH changes during ripening was also not significant in general, while levels of pH were decrease markedly during manufacturing and the initial stage of ripening. 4) The levels of bacterial counts were much higher in case of skim milk addition throughtout the ripening period. In general the numbers were reached to approximately $10^8cells/g$ during manufacturing, then decreased gradually to below $10^2cells/g$ in 8 weeks of ripening. 5) The addition of skim milk and/or rennin resulted in higher ripening index, and skim milk plus Meito rennet extracts was appeared to be best combination for the ripening index.

• Korean Journal of Biological Psychiatry
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• v.15 no.4
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• pp.275-287
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• 2008

Depression and coronary artery disease are both highly prevalent diseases. Many previous studies suggest that depression is a common comorbid condition in patients with coronary artery disease and has a significant negative impact on the onset, course, and prognosis of coronary artery disease. However, the exact mechanisms that underlie the association between these two diseases remain unclear. Pathophysiologic mechanisms that may explain the effect of depression on coronary artery disease include hypercoagulability, hypothalamus-pituitary-adrenal axis and autonomic nervous system dysregulation, altered inflammatory response. On the contrary, pathophysiologic mechanisms in coronary artery disease that affect depression are less well known. It is also suggested that both diseases may share a common genetic vulnerability. The authors reviewed the literature on the pathophysiologic relationships of depression and coronary heart disease.

• Applied Biological Chemistry
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• v.8
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• pp.101-111
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• 1967

Daily doses of phenylmercuric acetate arranged in $30{\gamma}\;(group\;I)$, 3{\gamma}\;(group\;II)$ and $0.3{\gamma}\;(group\;III)$ were administered respectively to rabbits for 90 days. The chief histopathological changes in the organs and the analytical data on mercury residues in the excretion and liver were as follows. 1. Kidney: In group I, severe degrees of vacuolization and cloudy swelling were occurred in the epithelial cells of proximal convoluted tubules and severe cloudy swelling and coagulative necrosis were observed in the proximal straight tubules. There were many hyaline casts in the collecting tubules. In group II, moderate degrees of vacuolization and cloudy swelling were observed in the epithelial cells of proximal convoluted tubules and moderate cloudy swelling and coagulative necrosis were encountered in the proximal straight tubules. A little numbers of hyaline casts were located in the lumen of collecting tubules. In group III, slight degree of cloudy swelling were observed in the epithelial cells of proximal convoluted and straight tubules. 2. Liver: In group I, cloudy swelling, fatty changes and coagulative necrosis were observed in the central zone of hepatic lobules. Dissociation of hepatic cell cords was encountered. Hyperplsia of hepatic cells were remarkable in group II. No Pathological changes were observed in group III. 3. Spleen: Deposition of hemosiderin pigment was prominant in group I and small amount of the pigment was observed in group II. There were no pathological changes in group III. 4. Adrenal, colon and heart: No pathological changes were detected in all 3 groups. 5. In an average about 76.5% of mercury was excreted from group I, 85.4% from group II and 79.8% from group III. 6. Mercury content in the liver was 0.0348 g in group I, 0.00378 g and 0.00066 g in group II and group III respectively. 7. In general, as to increased mercury doses the concentration of mercury accumulation in the liver became higher, how·ever, the accumulation quantity against a total amount of mercury doses showed an adverse trend. In other word, the quantity of mercury accumulation was not increased proportionately by higher dose of mercury.

• Tribology and Lubricants
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• v.28 no.4
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• pp.178-183
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• 2012

The fuel system of a vehicle is a very important compotent, as it provides the firing resources to the combustion chamber of the engine. However, improper operation of the system can generate bad condition or start-off during engine revolution. This study analyzed several examples of failure that had originated in the field. In the first example, the driver operated a vehicle containing both gasoline and LPG in the fuel tank, but the gasoline fuel remained unused for a few months. Therefore the fuel pump was clogged because of gasoline congelation. The second example, dealt with fuel leakage that occurred from the slightly torn O-ring connecting the fuel lines. The third example, pertained to engine damage and power-down owing to the usage of proor-quality fuel and ingredient. Therefore, it is necessary to take adequate measures to prevent the failure of the fuel system of vehicle.

• Journal of the Korean Home Economics Association
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• v.17 no.1
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• pp.12-19
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• 1979

Five kinds of soybean curd were propared with five coagulants, such as, calcium sulfate, calcium chloride, magnesium chloride, glucono delta lactone and acetic acid. The products were evaluated by the sensory and objective examination. Optimal concentrations of each coagulant were determined. Soybean curd preparation was also standardized. The textural characteristics of the five soybean curds which were made by the standard recipe were measured by a Texturometer and a Penetrometer. The results were as follows : 1. From the proliminary study, the optimal concentration of coagulants for the soybean curd preparation, as determined by the sensory evaluation was 1.84% of calcium sulfute, 1.05% of calcium chloride. 1.84% of calcium sulfute, 1.05% of calcium chloride. 1.84% of magnesium chloride, 1.97% of glucono delta lactone and 0.48% 11of acetic acid. 2. As the result of the sensory evaluation, the most acceptable soybean curd was determined to be one with acetic acid. Next, in order of accetability , were magnesium chloride, calcium chloride, glucono delta lactone, calcium sulfate soybean curds and commerical soybean curd. 3. Through the objective examination of the five soybean curds by a Texturometer and a Penetrometer, it was found out that, calcium sulfate soybean curd was the hardest and the hardness decreased in order of glucono delta lactone, magnesium chloride, calcium chloride, and acetic acid soybean curd. Acetic acid soybean curd, the most acceptable , was 0.47 TU ; and calcium sulfate soybean curd, the least acceptable, was 1.73 TU.

• Microbiology and Biotechnology Letters
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• v.10 no.4
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• pp.283-288
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• 1982

Trypsin inhibitor produced by Streptomyces sp. was investigated its reactive characteristics against trypsin. The mode of inhibition against trypsin was mixed type of non-competitive and competitive with casein, and enzyme-inhibitor complex was formed rapidly. The inhibitory activity was increased by the addition of isoleucine and depressed by silver, mercuric or cupric ion. And when egg albumin or hemoglobin was used as substrate for trypsin, the inhibition ratio was changed. The inhibitor inhibited coagulation of blood of bovine.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2005.11a
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• pp.13-21
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• 2005

I consider the structure of steady wave system which is admitted by the continuum equations for materials that undergo phase transformations with exothermic chemical reaction. In particular, the dynamic phase front structures between liquid and gas phases, and solid and liquid phases are computationally investigated. Based on the one-dimensional continuum shock structure analysis, the present approach can estimate the nano-width of waves that are present in combustion. For illustration purpose, n-heptane is used in the evaporation and condensation analysis and HMX is used in the melting and freezing analysis of energetic materials of interest. On-going effort includes extension of this idea to include broad range of liquid and solid fuels, such as rocket propellants.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.40 no.3
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• pp.113-116
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• 2007

We investigated the characteristics of various Tofu coagulants extracted from sea tangle using treated deep ocean water (DOW) as the solvents. The coagulants were typical solutions extracted from sea tangle using raw DOW and strongly electrolyzed acidic (SAC) or alkaline (SAK) water. The total dissolved solids (TDS), NaCl and electric conductivity were increased in the coagulant solution extracted by SAC than the others. In the coagulant solutions extracted by acidic electrolyzed solvent, aspartic acid content (13.5 mg/100 g) was higher than others (11.2 and 12.1 mg/100 g). The Tofu obtained using coagulants extracted with treated DOW had the water contents ranging from 79.55% to 80.04%. The contents of crude protein (12.1 g/100 g) and Na, Ca, K and Mg were relatively higher than general Tofu commercially available. Therefore, coagulant solutions extracted from sea tangle using treated DOW can be used to develop natural high-grade tofu for practical use.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.3 no.1
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• pp.1-11
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• 1993

A suppression of turbulent fluid motion and a control of oxygen and dopants could be improved by application of magnetic field in Czochralski growth of silicon. The effect of an axial magnetic field on Czochralski system was numerically calculated. The fluid motions induced by temperature gradients and by crystal and crucible rotations were suppressed by magnetic force. The S/L interface was gradually flattened in proportion to the increase of magnetic field due to a reduced ascending velocity in the vicinity of center line. The t.emperature distributions in the melt at 8=0.3 Tesla were similar to those analyzed by the conduction heat transfer only. The dissipated amounts of heat flux from melt and crystal surfaces by Ar gas blowing was Jess than 3 %.