• 한국미생물·생명공학회지
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• 제43권4호
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• pp.314-321
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• 2015

대한민국 제주도 연안 해수로부터 agarase를 생산하는 균주 S4를 분리하였다. 균주 S4는 그람-음성의 막대형 세포로 부드러운 베이지색 원형 콜로니를 형성하며, 한 개의 극성 편모를 갖는다. S4 균주는 $15-42^{\circ}C$, 0.5-5%(w/v) NaCl, pH 6.0-9.0, 0.5-5%(w/v) NaCl 농도에서 안정된 성장을 보인다. S4 균주의 G+C content는 49.93 mol%, 세포내 주요 지방산 (>15%)은 $C_{18:1}{\omega}7c$, $C_{16:0}$, Summed feature 3(comprising $C_{16:1}{\omega}7c/iso-C_{15:0}$ 2-OH)이다. 16S rRNA 염기서열, 생화학적 및 분류학정 특징에 기초하여 S4 균주를 Vibrio sp. S4로 명명하였다. 0.1% agar를 첨가한 액체배지에서 S4 균주는 72시간에 세포농도와 agarase 활성이 최대치를 보였다. 반면, agar 를 첨가하지 않은 배양액에서의 agarase 활성은 무시할만한 수준이었으며, 이는 균주의 agarase 유전자 발현이 agar에 의해 유도됨을 시사하고 있다. 균주 S4가 세포외부로 분비하는 총 agarase는 $45^{\circ}C$와 pH 7.0에서 최상의 효소 활성을 보였으며, agarose를 분해하여 (neo)agarotetraose와 (neo)agarohexaose를 생산하였다.

• 한국수소및신에너지학회논문집
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• 제18권1호
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• pp.32-39
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• 2007

CO oxidation and selective CO oxidation of $La_xCe_{1-x}Co_yCu_{1-y}O_{3-{\alpha}}$ perovskite(x=1, 0.9, 0.7. 0.5; y=1, 0.9, 0.7, 0.5) were investigated. For CO oxidation, catalytic activities were studied according to different preparation conditions such as pH and calcination temperature. The influence of the change of the $O_2$ concentration for selective CO oxidation was studied, too. The substitution of Ce for La improved the catalytic activity for CO oxidation and selective CO oxidation and best activity was observed for $La_{0.7}Ce_{0.3}CoO_3$ prepared at pH 11 and calcined at $600^{\circ}C$. The temperature of 90% CO conversion for CO oxidation using $La_{0.7}Ce_{0.3}CoO_3$ was $230^{\circ}C$. In contrast to the enhancement effect by Ce substitution, the partial substitution of Cu for Co in $LaCo_yCu_{1-y}O_{3-{\alpha}}$ decreased catalytic activities for CO oxidation reaction compared to that using $LaCoO_3$. For selective CO oxidation, the best CO conversion was 66% at $230^{\circ}C$ for $La_{0.7}Ce_{0.3}CoO_3$. The CO conversion of $La_{0.7}Ce_{0.3}CoO_3$ was greatly increased from 66% to 91% as increasing $O_2$ concentration from 1% to 2%.

• 대한약학회:학술대회논문집
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• 대한약학회 2003년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.1
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• pp.143.1-143.1
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• 2003

In this study. we investigated whether the cardioprotective effect shown by quercetin 3-O-$\alpha$-arabinofuranoside extracted from Lindera erythrocarpa against ROS-induced cell death in H9c2 cardiac myocytes. Cell death was induced by BSO, buthionine sulfoximine, which inhibits GSH level and subsequntly increase ROS level. Cell death was quntitatively determined by measuring lactate dehydrogenase (LDH) activity. (omitted)

• 한국식품과학회지
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• 제53권6호
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• pp.775-784
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• 2021

Clostidium butyricum을 분리하기 위하여 국내 모유수유 신생아 분변으로부터 혐기성 균주를 선별하였고 버블을 생성하는 100개의 균을 확보하였다. 이중 Clostridium perfringens에 대한 항균력과 butyric acid의 생산이 가장 우수한 DIMO 52 균주를 선발하였고, 형태학적 특성, 생리 생화적 특성 및 16S rRNA 유전자 분석을 통하여 C. butyricum으로 동정되어 C. butyricum DIMO 52로 명명하였다. 성장률, butyric acid 생산 및 pH 변화를 배양 36시간 동안 모니터링하였다. 배양 24시간 후 DIMO 52 균주의 최대 성장에 도달하였고, butyric acid 최대 농도는 대략 34.73±4.27 mM이었으며, pH는 7.2에서 2.5로 변경되었다. DIMO 52 균주는 낮은 pH와 oxgall에 높은 저항성이 있다. pH 2에서 2시간 동안 접종의 약 67.5%의 유의성 있는 생존율을 보였다(p<0.05). 그리고, 0.3% oxgall이 함유된 RCM 액체배지에서 24시간 동안 접종의 약 64.9%의 유의성 있는 생존율을 보였다(p<0.05). 또한, DIMO 52은 Escherichia coli KCTC 2441와 Salmonella Typhimurium KCTC 1925에 대해 억제효과를 나타냈다. 두 균주에 대한 항균효과는 아마도 butyric acid에 의한 낮은 pH 때문인 것으로 보였다. 5×10³ CFU/mL 생균수 까지는 RAW264.7 세포에 세포독성이 없는 것으로 관찰되었고, NO 생성을 억제할 수 있는 최저 균수를 확인한 결과 약 1×10³ CFU/mL 생균수에서 LPS만 처리한 군 대비 약 33%의 NO 생성을 억제하는 것으로 분석되었다(p<0.01). 이 결과는 C. butyricum DIMO 52이 NO radical 소거 및 항염증 활성을 가지고 있음을 시사한다. 결론적으로, 본 연구에서 분리된 C. butyricum DIMO 52의 프로바이오틱스 특성을 확인하였다.

• 한국가축번식학회지
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• 제19권2호
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• pp.95-104
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• 1995

Mouse mammary epithelial cells(NMuMG) were maintained onto 6-well plates (3$\times$105 cells/well) or chambered slide (1$\times$104 cells/well), in DMEM supplemented with 10% fetal calf serum. After serum starvation for 24 hours, DMNB (1$\mu$M) was added and exposed to UV light (300nm, 3 second pulse) after 2 hours from DMNB addition in order to activate DMNB which induces a rapid transient increase in intracellular cAMP upon UV irradiation. EGF (100ng/ml) and/or IGF-I (10ng/ml) were treated at the time of UV irradiation. Nuclear labeling index was estimated as percent of nuclear labeled cells(percent of S phase of cells) by incorporation of 3H-thymidine into DNA(1 hour pulse with 1$\mu$Ci/ml). DMNB(1$\mu$M), EGF (100ng/ml) and/or IGF-I (10ng/ml) signifciantly increased nuclear labeling index than those of control (P<0.05). Addition of DMNB＋EGF or DMNB＋EGF＋IGF-I showed the interaction effect in nuclear labeling index (P<0.05). Protein kinase A activities by addition of EGF, IGF-I or EGF＋IGF-I were 10.5, 9.8 or 9.4 unit/mg protein, respectively, and no statistical difference was found in comparison with control (P>0.05). Additon of DMNB＋EGF showed the moderate interaction effect on tyrosyl kinase activity (P<0.1). In the fluorography analysis, there were no specific protein phosphorylation patterns were found at 1 or 15 minute by addition of DMNB. EGF and/or IGF-I. These results suggest that the interaction effect in nuclear labeling index by addition DMNB and EGF could be mediated through the modulation of tyrosyl kinase activity by cAMP.

• 동의생리병리학회지
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• 제18권5호
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• pp.1418-1425
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• 2004

The water extract of Chongmyung-tang has been traditionally used for treatment of memory-disorder in oriental medicine. This study was designed to investigate the protective mechanisms of Chongmyung-tang on β-amyloid or H₂O₂-induced cytotoxicity in Neuro 2A cells. The water extract of Chongmyung-tang significantly reduced both β-amyloid or H₂O₂-induced cell death and apoptotic characteristics through reduction of intracellular peroxide generation. Also, it inhibited the mitochondrial dysfunction including the disruption of mitochondria membrane permeability transition(MPT) and the modulation in expression of Bcl-2 family proteins in H₂O₂-treated H9c2 cells. Furthermore, pretreatment of quercetin inhibited the activation of caspase-3, in turn, degradation of ICAD/DFF45 were completely abolished in H₂O₂-treated cells. Taken together, that data suggest that the protective effects of the water extract of Chongmyung-tang against β-amyloid induced oxidative injuries may be achieved through modulation of mitochondrial dysfunction.

• Asian Pacific Journal of Cancer Prevention
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• 제17권3호
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• pp.1553-1564
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• 2016

Identification of novel therapeutics in glioblastoma remains crucial due to the devastating and infiltrative capacity of this malignancy. The current study was aimed to appraise effect of arsenic trioxide (ATO) in U87MG cells. The results demonstrated that ATO induced apoptosis and impeded proliferation of U87MG cells in a dose-dependent manner and also inhibited classical NF-${\kappa}B$ signaling pathway. ATO further upregulated expression of Bax as an important proapoptotic target of NF-${\kappa}B$ and also inhibited mRNA expression of survivin, c-Myc and hTERT and suppressed telomerase activity. Moreover, ATO significantly increased adhesion of U87MG cells and also diminished transcription of NF-${\kappa}B$ down-stream targets involved in cell migration and invasion, including cathepsin B, uPA, MMP-2, MMP-9 and MMP-14 and suppressed proteolytic activity of cathepsin B, MMP-2 and MMP-9, demonstrating a possible mechanism of ATO effect on a well-known signaling in glioblastoma dissemination. Taken together, here we suggest that ATO inhibits survival and invasion of U87MG cells possibly through NF-${\kappa}B$-mediated inhibition of survivin and telomerase activity and NF-${\kappa}B$-dependent suppression of cathepsin B, MMP-2 and MMP-9.

• Nutrition Research and Practice
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• 제13권3호
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• pp.196-204
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• 2019

BACKGROUND/OBJECTIVES: Non-alcoholic fatty liver disease (NAFLD) is a common metabolic disease triggered by epigenetic alterations, including lysine acetylation at histone or non-histone proteins, affecting the stability or transcription of lipogenic genes. Although various natural dietary compounds have anti-lipogenic effects, their effects on the acetylation status and lipid metabolism in the liver have not been thoroughly investigated. MATERIALS/METHODS: Following oleic-palmitic acid (OPA)-induced lipid accumulation in HepG2 cells, the acetylation status of histone and non-histone proteins, HAT activity, and mRNA expression of representative lipogenic genes, including $PPAR{\gamma}$, SREBP-1c, ACLY, and FASN, were evaluated. Furthermore, correlations between lipid accumulation and HAT activity for 22 representative natural food extracts (NExs) were evaluated. RESULTS: Non-histone protein acetylation increased following OPA treatment and the acetylation of histones H3K9, H4K8, and H4K16 was accelerated, accompanied by an increase in HAT activity. OPA-induced increases in the mRNA expression of lipogenic genes were down-regulated by C-646, a p300/CBP-specific inhibitor. Finally, we detected a positive correlation between HAT activity and lipid accumulation (Pearson's correlation coefficient = 0.604) using 22 NExs. CONCLUSIONS: Our results suggest that NExs have novel applications as nutraceutical agents with HAT inhibitor activity for the prevention and treatment of NAFLD.

• Journal of Microbiology and Biotechnology
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• 제11권1호
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• pp.40-49
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• 2001

The present work presents a novel approach for the dynamic quantification of respiration rates on a small scale by using lysine-producing Corynebacterium glutamicum ATCC 21253. Cells sampeld from batch cultures at different times were incubated ina 12-ml scale bioreactor equipped with a membrane mass spectrometer. Under dynamic conditions, gas exchange across the gas-liquid phase, specific respiration rates, and RQ values were precisely measured. For this purpose, suitable mass balances were formulated. The transport coefficients for $O_2$ and $CO_2$, crucial for calculating the respiration activity, were determined as $k_La_{O2}=9.18h^{-1}$ and $k_La_{CO2}=5.10h^{-1}$ at 400 rpm. The application of the proposed method to batch cultures of C. glutamicum ATCC 21253 revealed the maximum specific respiration rates of $q_{O2}=8.4\;mmol\;g^{-1}h^{-1}\;and\;q_{CO2}=8.7\;mmol\;g^{-1}h^{-1}$ in the middle of the exponential growth phase after 5 h of cultivation. When the cells changed from growth to lysine production due to the depletion of the essential amino acids theonine, methionine, and leucine, $q_{O2}\;and\;q_{CO2}$ decreased significantly and RQ increased. The respiration data exhibited an excellent agreement with previous cultivations of the strain [13]. This confirms the potential of the developed approach to realistically reflect the metabolic activities of cells at their point of sampling. The short-term influence of added threonine, methionine, and leucine was highest during the shift from growth to lysine production, where $q_{O2}\;and\;q_{CO2}$ increased 50% within one minute after the pulse addition of these compounds. Non-growing, yet lysine-producing cells taken from the end of the batch cultivation revealed no metabolic stimulation with the addition of threonine, methionine, and leucine.

• Asian Pacific Journal of Cancer Prevention
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• 제13권8호
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• pp.3803-3807
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• 2012

Prohibitin (PHB), an evolutionarily-conserved protein, has been found to be over-expressed in gastric cancer and be closely related with tumor malignancy. In this study, to investigate the relationship between PHB expression and cell apoptosis in the BGC823 gastric cancer cell line, low and high expression PHB in BGC823 cells was accomplished using RNA interference technology and gene transfer techniques. Cell proliferation, cell cycling, apoptosis, Bax, Bcl-2 and Cyt.c protein expression and the activation of Caspase-3,9 were assessed after 48h. Over-expression of PHB gene in BGC823 cells resulted in slow cell growth, cell arrest in G2 phase, and an increased apoptosis ratio while the opposite was found for PHB under-expressing cells. In PHB over-expressing cells, the expression of Bax gene was increased, the expression of Bcl-2 was decreased, the activation level of Caspase-3, 9 was increased, but the activation level of Caspase-8 demonstrated no change. These results indicate that PHB induced apoptosis through the mitochondrial pathway.