• 한국식품과학회지
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• 제36권6호
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• pp.1001-1007
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• 2004

암세포 성장 억제효과가 인정된 산수유 methanol 추출물의 chloroform층으로부터 silica gel column과 thin layer chromato-grapies를 이용하여 항암활성물질을 분리하고, IR, mass spectrometer, $^1H-NMR$ 및 $^{13}C-NMRs$을 통해 순수물질을 동정하였다. 이 물질은 triterpenoid로서 $C_{30}H_{48}O_3$의 구조식을 가진 화합물로 분자량이 456인 ursolic acid($3{\beta}$-hydroxyrus-12-ene-28-oic acid)로 동정되었다. 정제된 화합물을 A549 및 MCF-7 암세포주에 48시간동안 처리한 결과 농도 의존적으로 암세포주의 성장을 억제하였으며, 화합물을 처리하지 않은 대조구에 비하여 $30\;{\mu}g/mL$농도로 처리시 40% 이상 그 성장을 억제하였으며, $100\;{\mu}g/mL$농도로 처리시 90% 이상 그 성장을 억제하였다. 정제 화합물을 처리한 암세포를 광학현미경으로 관찰한 결과 뚜렷한 세포수의 감소와 함께 심한 형태학적 변화가 관찰되었다. 암세포 주에 정제시료를 $10\;{\mu}g/mL$농도로 처리하고, 15시간 배양한 후 세포주기를 분석한 결과 sub-G1 phase의 비율이 A549의 경우는 대조구에서 4.0%이었던 것이 11.7%로, MCF-7의 경우는 대조구에서 2.1%이었던 것이 처리구에서는 11.2%로 각각 증가된 것으로 나타나 정제물질은 apoptosis에 의한 세포사멸 유도를 시사하였다.

• Journal of Microbiology and Biotechnology
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• 제17권5호
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• pp.769-773
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• 2007

With the aim to produce ascorbic acid-2-phosphate(AsA-2-P) from L-ascorbic acid(AsA, Vitamin C), nine bacteria conferring the ability to transform AsA to AsA-2-P were isolated from soil samples alongside known strains from culture collections. Most isolates were classified to the genus Brevundimonas by 16S phylogenetic analysis. Among them, Brevundimonas diminuta KACC 10306 was selected as the experimental strain because of its the highest productivity of AsA-2-P. The optimum set of conditions for the AsA-2-P production from AsA using resting cells as the source of the enzyme was also investigated. The optimum cultivation time was 16 h and the cell concentration was 120g/l(wet weight). The optimum concentrations of AsA and pyrophosphate were 550mM and 450mM, respectively. The most effective buffer was 50mM sodium formate. The optimum pH was 4.5 and temperature was $40^{\circ}C$. Under the above conditions, 27.5g/l of AsA-2-P was produced from AsA after 36 h of incubation, which corresponded to a 19.7% conversion efficiency based on the initial concentration of AsA.

• 한국항행학회논문지
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• 제15권4호
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• pp.495-501
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• 2011

GPS 수신기의 신호 추적 루프에서 추적 오차를 추정하는 판별기(Discriminator)의 특성은 잡음 전력에 의해 영향을 받으며, 실제로 판별기 함수의 기울기는 잡음 전력이 커질수록 작아지는 특성을 보인다. 본 논문에서는 추정한 C/N0를 이용하여 작아진 기울기를 보상할 수 있는 방법을 연구하였으며, GPS 수신기의 신호 추적 루프중에서 측위 성능에 직접적인 영향을 주는 코드 추적 루프에 적용함으로써 일반적인 판별기보다 더 정확한 추적 오차를 가지는 코드 추적 루프 설계 기법을 제안한다. 또한 모의실험 결과로부터 20g/s의 기동을 갖는 항체에 대하여 제안한 코드 추적 루프의 정확도가 약 50% 개선되는 것을 확인하였다.

• BMB Reports
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• 제36권2호
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• pp.185-189
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• 2003

Chitinase (EC 3.2.1.14) was isolated from the culture filtrate of Streptomyces sp. M-20 and purified by ammonium sulfate precipitation, DEAE-cellulose ion-exchange chromatography, and Sephadex G-100 gel filtration. No exochitinase activity was found in the culture filtrate. The molecular mass of the purified chitinase was 20 kDa, estimated by a sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and was confirmed by activity staining with Calcofluor White M2R. Chitinase was optimally active at pH of 5.0 and at $30^{\circ}C$. The enzyme was stable from pH 4 to 8, and up to $40^{\circ}C$. Among the metals and inhibitors that were tested, the $Hg^+$, $Hg^{2+}$, and p-chloromercuribenzoic acid completely inhibited the enzyme activity. The chitinase activity was high on colloidal chitin, chitotriose, and chitooligosaccharide. The purified chitinase showed antifungal activity against Botrytis cinerea, and lysozyme activity against the cell wall of Botrytis cinerea.

• 한국균학회지
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• 제6권1호
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• pp.53-56
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• 1978

The carpophores of Mycroporus affinis (Blume et Nees) Kuntze which grows wildly in Korea were collected in the Gyeong Gi Province and extracted with chloroform and methanol. Two compounds were isolated from the extract and one of these compounds was identified as ergosterol by T.L.C., G.L.C. and chemical tests.

• 한국균학회지
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• 제6권1호
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• pp.1-4
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• 1978

Attempts were made to investigate the sterol components of Coriolus versicolor (Fr.) Quel, which is one of medicinal fungi and which grows wildly in Korea.Its carpophores were collected in the Gyeong Gi Province and extracted with chloroform and methanol. Four Compounds were isolated and one of these compounds was identified as ergosterol by T.L.C., G.L.C. and chemical tests. ${\beta}-Sitosterol$ appears to exist also in the carpophore.

• 한국해양학회지:바다
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• 제4권2호
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• pp.101-106
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• 1999

마산만 부영양화 진행과정을 파악하기 위하여 1994년 1월 모도부근 해저 주상퇴적물에 들어있는 엽록소 a, 유기탄소 및 유기물의 탄소 안정동위원소비(${\delta}^{13}C$) 수직분포를 조사하였다. 엽록소 a와 유기탄소함량은 퇴적물깊이가 증가함에 따라 감소하였다. 0~20 cm 깊이까지 평균 엽록소 a함량(페오피틴 a 제외)과 유기탄소함량은 각각 9.6 ${\mu}g\;g^{-1}$(건조중량), 2.5%로서 높다. 퇴적물중 엽록소 a 함량 수직분포와 퇴적율 및 분해속도를 근거로 추정하면 마산만 부영양화는 약 1960년대부터 가속화된 것으로 예상된다. 유기탄소:엽록소 a 비가 25라 가정한다면 해저최적물로 향하는 유기탄소 플럭스는 약 10 $gCm^{-2}yr^{-1}$이다. 이는 식물플랑크톤에 의해 고정된 탄소중 약 1.3%가 해저에 축적됨을 암시한다.

• 대한한방내과학회지
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• 제30권3호
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• pp.495-509
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• 2009

Objective : Membranous nephropathy(MN) is an organ-specific autoimmune disease and a relatively common cause of nephrotic syndrome in adults worldwide. But treatment of MN is not defined. This study was to evaluate the effects of Acasia Catechu extract(ACE) on the MN induced by cBSA in mice. Methods : Mice were divided into 4 groups. The normal group was injected with a saline solution. The control group was treated with cBSA(10 mg/kg i.p.) only. The third group was treated with cBSA (10 mg/kg i.p.) and ACE (250 mg/kg, p.o.). The fourth group was treated with cBSA (10mg/kg i.p.) and ACE (500mg/kg, p.o.). After cBSA and ACE treatment for 6 weeks, we measured change of body weight, 24hrs proteinuria, serum albumin, total cholesterol, triglyceride, BUN, creatinine, TNF-$\alpha$, IL-6, IL-$1{\beta}$, IFN-$\gamma$, IgA, IgM and IgG levels. The morphologic changes of renal glomeruli were also observed with a light microscope. Results : The levels of 24 hrs proteinuria, total cholesterol, triglyceride, IgG, IgM, IgA, TNF-$\alpha$, IL-6, IL-$1{\beta}$, IFN-$\gamma$ significantly decreased in both ACE groups. The level of albumin significantly increased in both ACE groups. The mRNA expression of IL-$1{\beta}$ in splenocytes considerably decreased in the ACE-500 group. In histological findings of kidney tissue, thickening of GBM decreased in both ACE groups. Conclusions : This study shows that ACE might be effective for treatment of MN. More clinical data and studies are to be done for efficient application.

• Macromolecular Research
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• 제17권12호
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• pp.1021-1024
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• 2009

We successfully prepared high-flow polycarbonate (PC) by blending commercial PC with a low molecular weight PC oligomer. The oligomer was synthesized by the addition of a large quantity of mono functional phenol groups, and the chain end group was reacted with p-tertiary butyl phenol (PTBP) to block the reactivity. The viscosity average molecular weight ($M_v$) for the oligomer was about 4,000-5,000 g/mol, compared to ~19,000 g/mol for the PC blend obtained by blending 10 wt% of the prepared oligomer with the commercial grade PC ($M_v$ of 21,000 g/mol). The blended PC had a melt flow index of 45, which is 2.5 times higher, and a processing temperature that was $20^{\circ}C$ lower, than that of commercial grade PC having a similar $M_v$.

• Journal of Applied Biological Chemistry
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• 제55권1호
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• pp.55-59
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• 2012

본 연구에서는 목재로부터 신속한 폼알데하이드 정량분석 시험법을 개발하고자 챔버법을 변형한 방법을 설계하였으며, 톱밥시료는 0.15-2.0 mm 크기의 입자를 사용하였고, 휘발부와 포집부가 분리된 장치에서 휘발온도 및 질소유량별 폼알데하이드 포집률을 측정하였다. 그 결과 질소유량 40 mL/min, $100^{\circ}C$ 조건에서 30분간 포집 할 경우 94.8%의 최대 포집률이 확인되었으며, 본 공정의 농도별 폼알데하이드 포집률은 71.0-94.8% ($r^2$=0.9968)로 확인되었으며, 목재 중 총 폼알데하이드 농도가 증가 할수록 휘발된 폼알데하이드량이 정량적으로 증가함을 확인할 수 있었다($r^2$=0.8234). 목재종류 별 폼알데하이드 평균 함량은 천연톱밥(0.7-4.6 ${\mu}g/g$), 방부목(3.9-5.6 ${\mu}g/g$), 접착제 사용 가공목재(5.9-211.5 ${\mu}g/g$) 순으로 낮은 함량을 확인하였고, 각 그룹별 폼알데하이드 분석결과에 대한 Duncan's multiple range test 수행결과 천연톱밥과 접착제를 사용하지 않는 방부목은 95% 신뢰수준에서 유의적 차이를 나타내지 않았으나, 천연톱밥과 접착제 사용목재간에는 동일 수준에서 유의차가 확인되었다. 이러한 결과로 볼 때, 접착제가 사용된 목재는 본 시험분석을 통해 신속하게 천연목재와 구분이 가능 할 것으로 판단된다.