• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.21 no.3
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• pp.236-241
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• 2008

The effect of organic solvent mixture ratio on the rheology property of slurry and thickness control of ceramic green sheet was investigated. For selecting a suitable dispersant multiple light scattering method was used to evaluate the particle migration velocity and variation of clarification layer thickness. Using the selected dispersant the dispersion property of solution according to solvent mixture ratio was investigated. Binder and plasticizers were added to formulate slurries and their viscosity was evaluated according to solvent mixture ratio. Ceramic green sheets with average thickness of 30, 50 urn were fabricated via tape casting and their thickness tolerances measured. As a result according to solvent mixture ratio the solution and slurry properties varied and for the mixture ratio of ethanol/toluene of 80/20 the ceramic green sheet with the lowest thickness tolerance was obtained.

• Journal of Microbiology and Biotechnology
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• v.27 no.6
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• pp.1171-1179
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• 2017

Butanol is a promising alternative to ethanol and is desirable for use in transportation fuels and additives to gasoline and diesel fuels. Microbial production of butanol is challenging primarily because of its toxicity and low titer of production. Herein, we compared the transcriptome and phenome of wild-type Escherichia coli and its butanol-tolerant evolved strain to understand the global cellular physiology and metabolism responsible for butanol tolerance. When the ancestral butanol-sensitive E. coli was exposed to butanol, gene activities involved in respiratory mechanisms and oxidative stress were highly perturbed. Intriguingly, the evolved butanol-tolerant strain behaved similarly in both the absence and presence of butanol. Among the mutations occurring in the evolved strain, cis-regulatory mutations may be the cause of butanol tolerance. This study provides a foundation for the rational design of the metabolic and regulatory pathways for enhanced biofuel production.

• Bulletin of Food Technology
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• v.23 no.2
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• pp.214-219
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• 2010

Saccharomyces cerevisiae는 전통적으로 알코올 음료와 bioethanol 생산에 이용되지만, 발효가 진행되는 동안 효모의 에탄올 생성은 에탄올의 축적에 의한 충격으로 세포활성에 손상을 초래한다. 본 연구는 S. cerevisiae의 에탄올 스트레스 반응과 에탄올 내성의 분자적 기초에 관해 수행되었으며, 에탄올 스트레스가 진행되는 동안 효모의 에탄올 생성 향상을 위한 유전 공학 전략의 수립에 활용될 수 있다. 이전의 연구들은 유전자 발현에 대한 에탄올 스트레스의 충격이 환경적 영향을 받기 때문에 다양한 균주와 조건들에 관해 이루어졌다. 그러나 에탄올 공격에 의해 영향을 받은 gene ontology 범주에서의 일부 공통점은 S. cerevisiae의 에탄올 스트레스 반응이 해당과정 및 미토콘드리아 기능과 관련된 유전자 발현의 증가와 에너지가 요구되는 성장과정과 관련된 유전자의 발현 감소에 따라 에너지 생산에 제약 받음을 의미한다. Genomewide screens를 이용한 연구는 vacuole function의 유지가 에탄올 내성에 대해 중요함을 암시한다. 아마도 단백질 turnover와 이온 항상성 유지에 이 세포기관의 역할이 중요하기 때문인 것으로 사료된다. 특히 에탄올 스트레스가 일어날 때 핵 내 Asr1과 Rat8의 축적은 비록 이 가설이 논란이 많은 주제로 남아있지만 S. cerevisiae가 에탄올 스트레스에 대한 특별한 반응을 가지고 있음을 의미한다.

• Microbiology and Biotechnology Letters
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• v.22 no.6
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• pp.571-576
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• 1994

One strain of cellulose-producing Acetobacter was isolated from the traditionally fermen- ted grape vinegar in Korea. The isolated strain, designated as KI strain was identified as the Acetobacter xylinum with respect to physiological and biochemical characteristics. KI produced acetic acid from ethanol, and then decomposed acetate to CO$_{2}$ and H$_{2}$O. When the isolated strain was cultivated statically in broth culture, a thick cellulose pellicle was formed. KI was tolerance of 8% ethanol and 30% glucose, and the isolate was positive in ketogenesis from glycerol, $\gamma$-pyrone from glucose and fructose, and 2-ketogluconic acid from glucose. KI strain possessed straight-chain C$_{18:1}$, C$_{16:0}$, and C$_{14:0}$ fatty acid, and contained ubiquinone Q$_{9}$ and Q$_{10}$ as isoprenoid quinone. DNA base composition of KI strain was 57.6% G+C.

• Journal of Chest Surgery
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• v.12 no.4
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• pp.383-394
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• 1979

Treatment of valvular heart disease with valve replacement has been one of the most popular procedures in cardiac surgery recently. Although, first effort was directed toward the prosthetic valve, it soon became popular that bioprosthesis, the valvular xenograft, was prefered in the majority cases. Valvular xenograft has some superiority to the artificial prosthetic valve in some points of thromboembolism and hemolytic anemia, and it also has some inferiority of durability, immunologic reaction and resistance to Infection. Tremendous efforts were made to cover the inferiority with several methods of collection, preservation, and valve mounting of the porcine valve or pericardium of the calf, and also with surgical technique of the valvular xenograft replacement. Auther has collected 320 porcine aortic valves immediately after slaughter, and aortic cusps were coapted with cotton balls in the Valsalva sinuses to protect valve deformity after immersion in the Hanks' solution, and oxidation, cross-linking and reduction procedures were completed after the proposal of Carpentier in 1972. Well preserved aortic valves were suture mounted in the hand-made tissue valve frame of 19, 21, and 23 mm J.d., and also in the prosthetic vascular segment of 19 mm Ld. with 4-0 nylon sutures after careful trimming of the aortic valves. Completed valves were evaluated with bacteriologic culture, pressure tolerance test with tolerane gauge, valve durability test in the saline glycerine mixed solution with tolerance test machine in the speed of 300 rpm, and again with pathologic changes to obtain following results: 1. Bacteriologic culture of the valve tissue in five different preservation method for two weeks revealed excellent and satisfactory result in view of sterilization including 0.65% glutaraldehyde preservation group for one week bacteriologic culture except one tissue with Citobacter freundii in 75% ethanol preserved group. 2. Pressure tolerance test was done with an apparatus composed of V-connected manometer and pressure applicator. Tolerable limit of pressure was recorded when central leaking jet of saline was observed. Average pressure tolerated in each group was 168 mmHg in glutaraldehyde, 128 mmHg in formaldehyde, 92 mmHg in Dakin's solution, 48 mmHg in ethylene oxide gas, and 26 mmHg in ethanol preserved group in relation to the control group of Ringer's 90 mmHg respectively. 3. Prolonged durability test was performed in the group of frame mounted xenograft tissue valve with 300 up-and-down motion tolerance test machine/min. There were no specific valve deformity or wearing in both 19, 21, and 23 mm valves at the end of 3 months (actually 15 months), and another 3 months durability test revealed minimal valve leakage during pressure tolerance test due to contraction deformity of the non-coronary cusp at the end of 6 months (actually 30 months) in the largest 23 mm group. 4. Histopathologic observation was focussed in three view points, endothelial cell lining, collagen and elastic fiber destructions in each preservation methods and long durable valvular tolerance test group. Endothel ial cell lining and collagen fiber were well preserved in the glutaraldehyde and formaldehyde treated group with minimal destruction of elastic fiber. In long durable tolerance test group revealed complete destruction of the endothelial cell lining with minimal destruction of the collagen and elastic fiber in 3 month and 6 month group in relation to the time and severity. In conclusion, porcine xenograft treated after the proposal of Carpentier in 1972 and preserved in the glutaraldehyde solution was the best method of collection, preservation and valve mounting. Pressure tolerance and valve motion tolerance test, also, revealed most satisfactory results in the glutaraldehyde preserved group.

• Proceedings of the Ginseng society Conference
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• 1988.08a
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• pp.25-27
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• 1988

To assess the effect of Panax ginseng on the detoxification of ethanol. we examined its effect on blood ethanol clearance in both man and experimental animals and on the rate of ethanol oxidation to carbon dioxide in experimental animals. Fourteen healthy male volunteers were subject to studies. The blood alcohol level in the test group receiving ginseng extract (3g/kg b.w.) along with alcohol (70g/65kg b.w.) was about $35\%$ lower than their control levels at 40 min after ethanol intake. When the blood alcohol level was compared on individual bases. blood alcohol concentrations in 10 subjects ranged from 32 to $51\%$ lower than their control values. The remaining 4 subjects appeared to have a high tolerance level. In experimental animals. the blood alcohol clearance was also much faster in test animals receiving ginseng along with ethanol. The rate of ethanol elimination was determined by the amount of $^{14}CO_2$ in exhaled air following the administration of [$^{14}C$] ethanol. During the first 7 1/4 hr (Phase I) after the ethanol administration. the $CO_2$ output was greater in test animals receving ginseng along with ethanol. whereas from beyond 7 1/4 hr to the near end (Phase II). the $CO_2$ output in control animals was over twice that in test animals. The present studies clearly demonstrate that ginseng promotes the overall metabolism of ethanol. resulting in an enhanced blood alcohol clearance and alcohol elimination.

• Journal of the Korean Society of Food Science and Nutrition
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• v.46 no.10
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• pp.1216-1224
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• 2017

Acetic acid bacteria strains were isolated from commercial natural vinegar. Ten isolated strains were identified using 16S rRNA gene sequencing data after evaluating the ethanol- and sulfur-tolerance. Eight of the strains isolated were identified as Acetobacter pasteurianus. A. pasteurianus JAC002, JAC005, and JAC008 strains, which showed a high ethanol tolerance, were selected for making "Makgeolli seed-vinegar". Rice wine vinegars were manufactured with the selected strains through fermentation, and their physicochemical properties and antimicrobial activities were evaluated. A. pasteurianus JAC002 strain showed the highest oxidation ability to acetic acid from ethanol on the twentieth day of fermentation, resulting in 4.21% total acidity, 3,791.77 mg% acetic acid content, and 2,931.78 mg% ethanol consumption content. Rice wine vinegar manufactured with the A. pasteurianus JAC002 strain showed increased antimicrobial activities against Staphylococcus aureus (KACC1927) and Escherichia coli (KACC10115). As a result, A. pasteurianus JAC002 strain was found to be the most suitable strain for "Makgeolli seed-vinegar".

• Advances in Traditional Medicine
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• v.10 no.2
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• pp.90-102
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• 2010

Effect of ethanol (ASE) and water (ASW) extracts of Argyreia speciosa on blood glucose and lipid profile was investigated in normoglycemic and Streptozotocin (STZ)-induced diabetic animals. In oral glucose and sucrose tolerance test, treatment with ASE and ASW (100 and 200 mg/kg) and Glidenclamide (10 mg/kg) significantly improved the glucose and sucrose tolerance in normal animals. In addition, respective treatment for fifteen-day resulted in significant percentage reduction in serum glucose (SG) ie., 30.39% (lower dose of ASE) and 33.21% (higher dose of ASW). In standardized STZ (50 mg/kg, iv)-induced diabetic rats, a single dose of ASE and ASW treatment exhibited reduction in SG levels at different time intervals compared to basal levels. Administration of both the doses of ASE and ASW for fifteen-day days exhibited greater percentage reduction in glycemia (24.6%, 24.7%, 23.9% and 21.9% respectively) and also ameliorated restored to near normal value of all tested lipid parameters. Further, treatment also exhibited significantly improved glucose tolerance over the period of 120 min compared to diabetic control group. Eventhough treatment failed to increase serum insulin levels significantly but peripheral utilization of insulin was increased as evident by insulin tolerance test. Taken together, present study supports the traditional usage of title plant in the treatment of diabetes mellitus.

• Microbiology and Biotechnology Letters
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• v.45 no.1
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• pp.51-56
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• 2017

Cellulosic biomass is a renewable source for biofuel production from non-edible biomass. An optimized pretreatment process is required for the efficient utilization of cellulosic biomass. Among various pretreatment processes, the use of ionic liquids has been reported recently. However, the residual ionic liquid after pretreatment acts as an inhibitor of microbial fermentation. Recently, we isolated mutant Saccharomyces cerevisiae strains resistant to the ionic liquid 1-ethyl-3-methylimidazolium acetate ([EMIM][Ac]) by using a directed evolutionary approach. When 3% [EMIM][Ac] was added to a medium containing 80 g/l of glucose, mutants D452-B2 and D452-S3 produced 35.6 g/l and 36.3 g/l of ethanol, respectively, for 18 h while the parental strain (S. cerevisiae D452-2) produced 1.3 g/l of ethanol. Thus, these mutant S. cerevisiae strains might prove advantageous when ionic liquids are used for biofuel production from cellulosic biomass.

• Membrane Journal
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• v.2 no.1
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• pp.33-48
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• 1992

OSRO process was developed and it was confirmed more effective in ethanol concentrating process comparing to reverse osmosis process. It may be industrialized if more effective membrane for OSRO and reverse osmosis, which indicate the value greater than zero, it was shown that OSRO process was more effective than reverse osmosis for the ethanol concentration process. The decrease of feed concentration and flow rate and the increase of applied pressure made more effective operating conditions in OSRO process to concentrate ethanol. From the numerical esults for the multi-plates, theoretical DC values of reverse osmosis and OSRO process was increased as the umber of stages increased. DC values were increased with the increase of applied pressure in same number of stages. The theoretical values of DC by numerical calculation were corresponded to the experimental values within 15% tolerance. DC value was increased proportional to applied pressure and osmotic sink solution flow rate but it was decreased proportional to feed concentration and flow rate. The numerical calculation over the wide ranges inclading experimental condition was proposed in this study.