• 제목/요약/키워드: B-GT

검색결과 131건 처리시간 0.025초

GT0236+610의 궤도에 따른 밝기 변화 연구

  • 김순욱
    • 한국지구과학회:학술대회논문집
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    • 한국지구과학회 2010년도 춘계학술발표회 논문집
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    • pp.112-112
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    • 2010
  • GT0236+618은 고중력 천체와 B0형별이 짝을 이루는 근접 쌍성계이다. 약 한 달을 주기로 공전함에 따라 그 밝기가 변하는데, 일반적으로는 두 별의 근일점 근처에서 많이 밝아지지만, 그 변화는 아주 규칙적이지는 않다. 예상외로 갑자기 더 많이 밝아지는 때가 각각 다른 이유는 잘 알려져 있지 않다. 고중력 천체의 정체도 동정되지 않은 상태이다. 가시광선 및 적외선을 이용한 GT0236+618의 최근 관측 연구를 소개하고자 한다.

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온도와 시간을 주요 변수로 한 냉장 돈육에서의 native isolated Listeria monocytogenes에 대한 성장예측모델 (Predictive Growth Model of Native Isolated Listeria monocytogenes on raw pork as a Function of Temperature and Time)

  • 홍종해;심우창;천석조;김용수;오덕환;하상도;최원상;박경진
    • 한국식품과학회지
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    • 제37권5호
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    • pp.850-855
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    • 2005
  • 본 연구는 냉장돈육에서의 식중독 원인균이면서 냉장온도에서 성장이 가능한 병원성균인 L. monocytogenes에 대한 적절한 위생관리를 제시하기 위하여 포장돈육 작업장 원료돈육에서 분리된 야생균주 L. monocytogenes 이용하여 돈육포장공정 및 유통조건에서의 L. mnocytogenes에 대한 성장예측모델을 제시하고자 실시하였다. 성장실험은 온도 5, 10, 15, $20^{\circ}C$ 시간은 0, 1, 2, 3, 18, 48, 120시간에서 실시하였으며, 이를 바탕으로 온도별 Gompertz value인 A, C, B, M의 값과 Growth kinetic인 exponential growth rate(EGR), generation time(GT), lag phase duration(LPD), maximum population density(MPD)를 산출하였다. GT, LPD는 온도가 상승할수록 그 값이 점점 낮아지는 경향을 나타났으며, EGR의 경우는 반대로 온도가 높아질수록 점점 높아지는 경향을 나타냈다. Gompertz value중 B와 M 값을 이용하여 온도를 주요 control factor로 선정한 반응표면분석(Response surface analysis)을 실시하여 온도에 따른 다항식을 산출하였고 이 식을 Gompertz 식에 적용하여 온도와 시간에 따른 냉장돈육에서의 L. monocytogenes에 대한 성장정도를 예측할 수 있는 성장예측모델을 제시하였다. 개발된 성장예측모델에 대한 검증은 GT, LPD, EGR에 대한 실험값과 예측값의 비교를 통하여 실시하였으며, 그 결과 GT, LPD, EGR 모두 통계적으로 유의하게 나타났다(p<0.01). 따라서 이 모델은 risk assessment 중 exposure assessment를 위한 성장예측모델로 충분히 이용가능 한 것으로 보이며, 추후 냉장돈육 위성관리기준에 대한 과학적 근거자료로 활용될 수 있을 것으로 보인다.

Exploration of the Glycosyltransferase BmmGT1 from a Marine-Derived Bacillus Strain as a Potential Enzyme Tool for Compound Glycol-Diversification

  • Liu, Quanquan;Ren, Pengfei;Liu, Yang;Qin, Wen;Li, Huayue;Li, Wenli
    • Journal of Microbiology and Biotechnology
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    • 제28권6호
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    • pp.931-937
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    • 2018
  • Glycosyltransferases (GTs) from microbes are an emerging and rich source for efficient glycol-transformation of natural/unnatural compounds. Here, we probed the catalytic capability and substrate promiscuity of BmmGT1 from marine-derived Bacillus methylotrophicus B-9987. The regioselectivity of BmmGT1 on macrolactin A (1) was explored by optimization of the reaction conditions, in which a series of O-glycosylated macrolactins (1a-1e) were generated, including two new di/tri-O-glucosyl analogs (1b and 1e). Furthermore, BmmGT1 was able to catalyze the glycosylation of the thiol (S-) or amine (N-) sites of phenolic compounds (2 and 3), leading to the generation of N- (2a) or S-glycosides (3a and 3b). The present study demonstrates that BmmGT1 could serve as a potential enzyme tool for O-, N-, or S-glycosyl structural diversification of compounds for drug discovery.

Similarities and differences between alpha-tocopherol and gamma-tocopherol in amelioration of inflammation, oxidative stress and pre-fibrosis in hyperglycemia induced acute kidney inflammation

  • Shin, Hanna;Eo, Hyeyoon;Lim, Yunsook
    • Nutrition Research and Practice
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    • 제10권1호
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    • pp.33-41
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    • 2016
  • BACKGROUND/OBJECTIVES: Diabetes mellitus (DM) is a major chronic disease which increases global health problems. Diabetes-induced renal damage is associated with inflammation and fibrosis. Alpha (AT) and gamma-tocopherols (GT) have shown antioxidant and anti-inflammatory effects in inflammation-mediated injuries. The primary aim of this study was to investigate effects of AT and GT supplementations on hyperglycemia induced acute kidney inflammation in alloxan induced diabetic mice with different levels of fasting blood glucose (FBG). MATERIALS/METHODS: Diabetes was induced by injection of alloxan monohydrate (150 mg/kg, i.p) in ICR mice (5.5-week-old, male) and mice were subdivided according to their FBG levels and treated with different diets for 2 weeks; CON: non-diabetic mice, m-DMC: diabetic control mice with mild FBG levels (250 mg/dl ${\leq}$ FBG ${\leq}$ 450 mg/dl), m-AT: m-DM mice fed AT supplementation (35 mg/kg diet), m-GT: m-DM mice with GT supplementation (35 mg/kg diet), s-DMC: diabetic control mice with severe FBG levels (450 mg/dl < FBG), s-AT: s-DM mice with AT supplementation, s-GT: s-DM mice with GT supplementation. RESULTS: Both AT and GT supplementations showed similar beneficial effects on $NF{\kappa}B$ associated inflammatory response (phosphorylated inhibitory kappa B-${\alpha}$, interleukin-$1{\beta}$, C-reactive protein, monocyte chemotactic protein-1) and pre-fibrosis (tumor growth factor ${\beta}$-1 and protein kinase C-II) as well as an antioxidant emzyme, heme oxygenase-1 (HO-1) in diabetic mice. On the other hands, AT and GT showed different beneficial effects on kidney weight, FBG, and oxidative stress associated makers (malondialdehyde, glutathione peroxidase, and catalase) except HO-1. In particular, GT significantly preserved kidney weight in m-DM and improved FBG levels in s-DM and malondialdehyde and catalase in m- and s-DM, while AT significantly attenuated FBG levels in m-DM and improved glutathione peroxidase in m- and s-DM. CONCLUSIONS: the results suggest that AT and GT with similarities and differences would be considered as beneficial nutrients to modulate hyperglycemia induced acute renal inflammation. Further research with careful approach is needed to confirm beneficial effects of tocopherols in diabetes with different FBG levels for clinical applications.

콩에서 분리한 근류균의 생리, 생화학적 특성 (Physiological and Biochemical Properties of Isolates of Rhizobia from Soybean)

  • 박기선;최재을
    • 한국식물병리학회지
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    • 제12권3호
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    • pp.351-357
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    • 1996
  • 콩으로부터 분리한 140균주의 근류균은 25균주(17.9%)가 Rhizobium fredii로 115 균주(82.1%)가 Brady-rhizobium japonicum으로 동정되었다. R. fredii에 속하는 분리 균주의 생존 pH 범위는 4..5∼9.0이었고 B. japonicum의 생육 pH 범위는 5.5∼8.0로 비교적 좁게 나타났다. B. japonicum에 속하는 98균주 중에서는 53균주(54%)가 IAA를 생산하지 않는 GT I group으로, 45균주(46%)는 IAA를 생산하는 GT II group으로 명확하게 구분되었으며, 항생물질에 대한 내성 유무에 의해 10개의 group으로 구분되었다.

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Gamma-tocopherol ameliorates hyperglycemia-induced hepatic inflammation associated with NLRP3 inflammasome in alloxan-induced diabetic mice

  • Lee, Heaji;Lim, Yunsook
    • Nutrition Research and Practice
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    • 제13권5호
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    • pp.377-383
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    • 2019
  • BACKGROUND/OBJECTIVES: Hyperglycemia-induced hepatic damage has been recognized as one of the major cause of complications in diabetes. Hepatic complications are associated with inflammation and oxidative stress in diabetes. In this study, we investigated the hypothesis that gamma-tocopherol (GT) supplementation ameliorates NLRP3 inflammasome associated hepatic inflammation in diabetes. MATERIALS/METHODS: Diabetes was induced by the intraperitoneal injection of alloxan (150 mg/kg. BW) in ICR mice. All mice were fed with a control diet (AIN-76A). After diabetes was induced (fasting glucose level ${\geq}250mg/dL$), the mice were treated with tocopherol-stripped corn oil or GT-supplemented (35 mg/kg) corn oil, respectively, by gavage for 2 weeks. RESULTS: GT supplementation reduced fasting blood glucose levels in diabetic mice relative to non-treated diabetic mice. Moreover, GT supplementation ameliorated hyperglycemia-induced hepatic damage by regulation of NOD-like receptor protein 3 (NLRP3)-inflammasome associated inflammation represented by NLRP3, apoptosis-associated speck-like protein containing a caspase-recruitment domain, caspase-1, nuclear $factor-{\kappa}B$ pathway as well as oxidative stress demonstrated by nuclear factor erythroid 2-related factor 2, NAD(P)H dehydrogenase quinone 1, catalase and glutathione-dependent peroxidase in diabetic mice. CONCLUSION: The findings suggested that GT supplementation ameliorated hepatic damage by attenuating inflammation and oxidative stress in alloxan-induced diabetic mice. Taken together, GT could be a beneficial nutrient that can ameliorate inflammatory responses associated with NLRP3 inflammasome in hyperglycemia-induced hepatic damage.

GREEN TEA AND ITS CATECHINS AS DIETARY AND PHARMACOLOGICAL MEANS OF LOWERING CHOLESTEROL ABSORPTION

  • Koo Sung I;Noh Sang K.;Loest Helena B;Wang Shu
    • 한국식품영양과학회:학술대회논문집
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    • 한국식품영양과학회 2001년도 International Symposium on Food,Nutrition and Health for 21st Century
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    • pp.74-87
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    • 2001
  • Evidence shows that the serum level of cholesterol (CH) is decreased with increasing green tea (GT) consumption. This presentation summarizes our recent findings on the effect of GT extract on intestinal absorption of [$^{14}C$-labeled CH and phosphatidylcholine (PC). Ovariectomized (OX) adult rats were infused intraduodenally with lipid emulsions containing radiolabeled lipids [$^{14}C$-CH or $^{14}C$-phosphatidylcholine (PC)] in the presence of GT extract or catechins to determine the rates and amounts of CH absorption and the intestinal hydrolysis and lymphatic output of PC. During lipid infusion, lymph was collected hourly for 8 h. The lymphatic absorption of $^14C$-CH was drastically lowered by infusion of GT extract at two dosage levels (GTl =5.4 mg catechins/h and GT2 = 15.1mg catechins/h). The cumulative lymphatic absorptions of $^{14}C$-CH in rats infused with GT1 and GT2 were 20.7$\pm$4.3 and $4.8{\pm}4.1{\%}$ dose, respectively, whereas the absorption of $^{14}C$-CH in rats infused with no GT extract (GT0) was $36.3{\pm}1.1{\%}$ dose. GT extracts also significantly lowered the absorption of-tocopherol (TP) in a dose dependent manner ($29.6{\pm}4.9{\%}$ dose in GT0, $20.8{\pm}5.8{\%}$ dose in GTl, and $7.9{\pm}5.4{\%}$ dose in GT2 groups). Both (+)-catechin and EGCG significantly lowered the lymphatic outputs of $^{14}C$-radioactivity after intraduodenal $^{14}C$-PC infusion. A significantly higher amount of $^{14}C$-PC remained unhydrolyzed in the intestinal lumen of the EGCG rats ($22.8{\%}$) compared with the (+)-catechin ($15.8\%$) and control groups ($11.9\%$). GT extracts, (+)-catechin, and EGCG significantly reduced the absorption of TP. The inhibitory effect of GT extract and catechins on lipid absorption may be mediated in part through the inhibition of pancreatic PLAz. The findings provide the first direct evidence that green tea and catechins have a profound inhibitory effect on the intestinal absorption of CH in OX rats. Results suggest that green tea and catechins may be used as a dietary or pharmacological means of lowering cholesterol absorption.

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연초의 적심방법이 품질구성형질에 미치는 영향 (Effect of Topping Method on the Quality Components of Flue-cured Tobacco)

  • 이종두;한종구;반유선;이정덕
    • 한국작물학회지
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    • 제33권1호
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    • pp.23-30
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    • 1988
  • 본 시험은 연초의 생육작황에 따라서 적심시기와 정도를 두어 처리하였을 때 잎담배의 품질형질에 미치는 영향을 구명코자 수행하였던 바 다음과 같은 결과를 얻었다. 1. 책상조직 및 발달은 적심시기에 따라 발뢰기&gt;개화시&gt;개화만기&gt; 만기 순으로 적심정도에 따라서는 치엽 4매&gt; 치엽 2매&gt; 화뢰 적심 순으로 발달되었다. 2. A급작황에서는 개화만기 B급작황에서는 개화시 치엽 2매를 적심할 때 끽미에 관련있는 전당/니코틴의 비는 9.0, 9.7로 가강 양호하였으며, 방향성 물질인 석유에텐추출물을 9.9%, 8.4%로 가장 높게 나타났다. 3. 품질에 크게 영향하는 요인은 생태조직과 건조엽중 내용성분으로 생태조직의 구성형질들이 품질에 직접 영향하는 효과를 보면 책상조직 43.2%, 해면조직 26.5%, 조직비 17.7%, 엽후 6.7%, 세포간극율 3.1 %, 엽형지수 2.8% 순이며, 내용성분 형질은 니코틴 40.6%, 전당/니코틴 35.7%, 전당 10.0%, 전질소/니코틴 7.0% 전질소 4.6%, 석유 에텔추출물 2.1% 순으로 품질에 영향을 미쳤다. 4. 양질엽 생산을 위해서는 수량이 10a당 250∼280kg 생산되는 A급작황에서는 개화만기에 치엽 2매 적심을, 200kg 내외 생산되는 B급작황에서는 개화시 치엽 2매를 붙여 적심하는 것이 가장 바람직 할 것으로 생각된다.

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프로펠러 레이싱에 대비한 SOFC/GT 하이브리드시스템의 대책 방안에 관한 기초적 연구 (A Study on Proposing Practicable Configurations against Propeller Racing for SOFC/GT Hybrid System in Ships)

  • 김명환;임태우
    • Journal of Advanced Marine Engineering and Technology
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    • 제32권2호
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    • pp.256-261
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    • 2008
  • The purpose of this study is to propose practicable configurations against Rapid Load Down like propeller racing of ships which have been using SOFC/GT hybrid system on board. This paper suggests four kinds of countermeasures against propeller racing. The types A and B keep a fixed load of SOFC and save a surplus electric power to a storage system. In types of C and D, the load of SOFC is changed with the propeller racing. The best desirable countermeasure for Rapid Load Down depends upon the size of the ship, the propulsion power, and the characteristics of the engine system.

한국산 다류(茶類)의 항(抗)지아민 영향에 관한 연구 (A Study on the Antithiamin Effects of Korean Teas)

  • 유양자;디 엠힐커
    • Journal of Nutrition and Health
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    • 제12권3호
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    • pp.33-39
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    • 1979
  • 우리나라에서 시판되고 있는 각종 다류(인삼차 2종, 인삼 extract 2종, 인삼분말, 생강차, 오미자차, 홍차, 인스턴트 홍차 2종)중의 antithiamin activity (ATA)와 탑닌함량을 정량하였 다. 한펀, Wistar계의 이유기의 숫쥐 30마리를 인스턴트홍차, 인삼차 B 인삼extract B와 Lipton tea 및 물 투여구(대조구)의 5군으로 나누어 일정향의 지아민을 첨가한 기본사료로 사육하면서 등물의 증체량, 사료 및 음료섭취량, 식이효율을 매주마다 측정하였고, 4주후 24시간 동안 각 투여구의 동물뇨중의 지아민의 함량을 비교하였다. 본 실험에서 사용한 다류중 ATA는 홍차 및 인스턴트 홍차 A가 가장 높았고, 인삼차 A와 오미자차는 비교적 낮았다. 일반적으로 ATA가 높은것은 탄닌의 함량도 많았고 ATA가 낮은 것은 탄닌의 함량도 낮은 경향이었으나, 같은 종류의 차라할지라도 ATA와 탄닌의 함량은 매우 상이하였다. 한편 동물실험에서 증체량은 인삼차 B와 인삼 extract B 투여구가 물, Lipton tea, 인스턴트 홍차 B 투여구에 비해 낮았으나 유의적인 차는 없었으며, 사료 및 음료섭취량, 식이효율도모든 실험구에서 유의적인 차가 없었다. 그리고 뇨중의 지아민 함량은 대조군에 비해 Lipton tea, 인삼차차 B, 인삼 extract구에서 높았고, 인스턴트 홍차 A구는 낮았으나 유의적인 차이는 없었다.

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