• 한국미생물학회:학술대회논문집
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• 한국미생물학회 2002년도 추계학술대회
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• pp.59-62
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• 2002

The role of a TolC homologue in the virulence of Vibrio vulnificus, a marine bacterium causing serious wound infection and fulminant septicemia in persons with underlying conditions, has been studied. TolC, an outer membrane protein, has been implicated in a variety of bacterial functions including export of diverse molecules ranging from large proteins to antibiotics. A homologue of the tolC gene of V. cholerae, which has been shown to be required for bile resistance, cytotoxicity and colonization of this organism, was identified in the partially determined genome sequence of V. vulnificus. To determine the role of TolC in the virulence of V. vulnificus, a TolC-deficient (TD) mutant was isolated by in vivo allelic exchange. Compared with the parent strain, the TD mutant was more sensitive to bile, and much less virulent in mice challenged subcutaneously. This mutant was noncytotoxic to the HEp-2 cells, but its metalloprotease and cytolysin activities in the culture supernatant were comparable to the parent strain. In addition, the resistance of the TD mutant to human serum bactericidal activity as well as its growth in either human or murine blood was not affected. Collectively, our data suggest that TolC may be involved in colonization and/or spread of V. vulnificus to the blood stream, probably by secreting a cytotoxin other than the cytolysin.

• Journal of Microbiology and Biotechnology
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• 제19권11호
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• pp.1328-1332
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• 2009

An activity-guided fractionation method was used to isolate anticancer components from Nuruk (Rhizopus oryzae KSD-815:KSD-815). Dried powder of KSD-815 was extracted with 80% methanol and partitioned successively using n-hexane, ethyl acetate, n-butanol, and water. The n-hexane and n-butanol fractions showed a strong antimigratory effect on human cancer cells. Both of these fractions were subjected to separation and purification procedures using silica gel, octadecyl silica gel, and Sephadex LH-20 column chromatographies to afford four purified compounds. These were identified as ergosterol peroxide (1), stigmast-5-en-$3\beta$,$7\beta$-diol (2), ergosta-7,22-dien-$3\beta$,$5\alpha$,$6\beta$,$9\alpha$-tetraol (3), and daucosterol (4), respectively, by spectroscopic methods such as nuclear magnetic resonance spectrometry, mass spectrometry, and infrared spectroscopy, and comparison with those in the literature. Compounds 1-4 were isolated from KSD-815 for the first time. Compounds 1 and 4 inhibited the migration of MDA-MB-231 cells at concentrations lower than $20\;{\mu}M$.

• Journal of Microbiology and Biotechnology
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• 제27권11호
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• pp.1925-1931
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• 2017

Korean red pine (Pinus densiflora) bark extract, PineXol (PX), was investigated for its potential antioxidant and anti-inflammation effects in vitro. It was hypothesized that PX treatment ($25-150{\mu}g/ml$) would reduce the lipid synthesis in HepG2 hepatocytes as well as lipid accumulation in 3T3-L1 adipocytes. Hepatocytes' intracellular triglycerides and cholesterol were decreased in the PX $150{\mu}g/ml$ treatment group compared with the control (p < 0.05). Consequently, de novo lipogenic proteins (acetyl-CoA carboxylase 1, stearoyl-CoA desaturase 1, elongase of very long chain fatty acids 6, glycerol-3-phosphate acyltransferase 1, and sterol regulatory element-binding protein 1) were significantly decreased in hepatocytes by PX $150{\mu}g/ml$ treatment compared with the control (p < 0.05). In differentiated 3T3-L1 adipocytes, the lipid accumulation was significantly attenuated by all PX treatments (p < 0.01). Regulators of adipogenesis, including CCAAT-enhancer-binding proteins alpha, peroxisome proliferatoractivated receptor gamma, and perilipin, were decreased in PX $100{\mu}g/ml$ treatment compared with the control (p < 0.05). In conclusion, PX might have anti-obesity effects by blocking hepatic lipogenesis and by inhibiting adipogenesis in adipocytes.

• 한국약용작물학회지
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• 제22권5호
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• pp.369-377
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• 2014

In order to find out anticancer activity of Korean pepper (Capsicum annuum L.), the cytotoxicity against 8 cell lines including 293 (normal kidney cells) and A-431 (epidermoid carcinoma cells) of extracts by extraction solvents and plant parts were investigated using MTT assay. Also the correlation between content of capsaicin known as anticancer ingredient and cytotoxicity of extracts from pepper were analyzed. The distilled water extracts from seed and germinated seed showed very high cytotoxicity against 6 cancer cell lines including A549 (lung carcinoma cells), AGS (stomach adenocarcinoma cells), HeLa (cervix adenocarcinoma cells), HepG2 (hepatoblastoma cells), HT-29 (colon adenocarcinoma cells), and MCF-7 (breast adenocarcinoma cells). But 80% ethanol and methanol extracts showed cytotoxicity against 293 and AGS. The $RC_{50}$, that was, the concentration of sample required for 50% reduction of cell viability, of seed and germinated seed extracts against AGS were $33.4{\sim}389.1{\mu}g/m{\ell}$ and $63.9{\sim}1,316.7{\mu}g/m{\ell}$, respectively, so anticancer activity was higher in seed than in germinated seed. In capsaicin contents, seed with high cytotoxicity and pericarp with a little cytotoxicity contained $47.4{\sim}1,260.0{\mu}g/g$ and $58.3{\sim}1,498.0{\mu}g/g$, respectively. As these results, the correlation was not between cytotoxicity and capsaicin content.

• 동의생리병리학회지
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• 제19권4호
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• pp.950-954
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• 2005

Phellinus linteus (Berk. & M.A. Curtis) Teng, commonly referred to as Sangwhang in Korea, is a well-known species of the genus Phellinus, which attracts great attention due to its phamarcological values. P. linteus has been reported to produce anti-tumor, anti-angiogenic, anti-mutagenic and immunomodulatory activities in vivo and in vitro. However, despite extensive biochemical studies on P. linteus, the wine produced by P. linteus fermentation (WPLF) has poorly investigated. In the present study, it was compared the in vitro cytotoxic effects of WPLF with ethanol as positive control. WPLF as well as ethanol induced the inhibition of cell proliferation and morphological changes in both HepG2 and A549 cells in a concentration-dependent manner, however, WPLG treatment has less cytotoxic effects than ethanol treatment. These cytotoxic effects were associated with the induction of apoptotic cell death, but, WPLG treatment has less apoptotisis inducing effects than ethanol treatment.

• Toxicological Research
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• 제30권1호
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• pp.19-25
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• 2014

Licochalcone (LC), a major phenolic retrochalcone from licorice, has anti-inflammatory activity. This study investigated the effects of licochalcone A (LCA) and licochalcone E (LCE) on Liver X receptor-${\alpha}$ ($LXR{\alpha}$)-mediated lipogenic gene expression and the molecular mechanisms underlying those effects. LCA and LCE antagonized the ability of $LXR{\alpha}$ agonists (T0901317 or GW3965) to increase sterol regulatory element binding protein-1c (SREBP-1c) expression and thereby inhibited target gene expression (e.g., FAS and ACC) in HepG2 cells. Moreover, treatment with LCA and LCE impaired $LXR{\alpha}/RXR{\alpha}$-induced CYP7A1-LXRE-luciferase (CYP7A1) transactivation. The AMPK-Sirt1 signaling pathway is an important regulator of energy metabolism and, therefore, a potential therapeutic target for metabolic diseases, including hepatic steatosis. We found here that LCE increased AMPK phosphorylation and Sirt1 expression. We conclude that LC inhibits SREBP-1c-mediated hepatic lipogenesis via activation of the AMPK/Sirt1 signaling pathway.

• 한국식품과학회지
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• 제43권3호
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• pp.396-400
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• 2011

We examined the in vitro mutagenic and antimutagenic effects of hexane-extracted hemp (Cannabis sativa L. subsp. sativa var. sativa) seed oil (HO) with and without S9-mediated metabolic activation, using the TA98 and TA100 Salmonella Typhimurium strains. The MTT assay revealed no cytotoxicity in HepG2 cells for HO quantities $\leq400g$/mL. In the mutagenicity test, revertant colonies did not exceed spontaneous colonies in number. Colony numbers did not increase in either strain after HO treatment, with or without metabolic activation. HO showed no mutagenic effects and did not induce a mutation in either strain. In the antimutagenicity test, HO reduced the number of mutated colonies induced by 4NQO in both strains. The inhibition rates of HO (TA98, 21-91%; TA100, 21-85%) indicated a potent reduction in mutagenicity induced by 4NQO. HO showed no significant mutagenicity and may have antimutagenic effects, as assessed by Ames testing.

• Macromolecular Research
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• 제8권6호
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• pp.276-284
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• 2000

A wettability chemogradient on poly(L-lactide-co-glycolide) (PLGA) films was prepared by treating the films in air with corona from a knife-type electrode whose power increases gradually along the sample length. The PLGA surfaces oxidized gradually with the increasing corona power, and the wettability chemogradient was created on the surfaces as evidenced by the measurement of water contact angles and electron spectroscopy for chemical analysis. The wettability chemogradient PLGA surfaces were used to investigate the interaction of four different types of cells such as hepatoma (Hep G2), osteoblast (MG 63), bovine aortic endothelial (CPAE), and fibroblast (NIH/3T3) cells in terms of the surface hydrophilicity/hydrophobicity of PLGA. The cells adhered and grown on the chemogradient surface along the sample length were counted and observed by scanning electron microscopy. It was observed that the cells were adhered, spread, and grown more onto the positions with moderate hydrophilicity of the wettability chemogradient PLGA surface than the more hydrophobic or hydrophillic positions, regardless of the cell types used. The maximum adhesion and growth of the cells appeared at around water contact angles of 53～55°. This result seems closely related with the serum protein adsorption on the surface; the serum proteins were also adsorbed more onto the positions with moderate hydrophilicity of the wettability chemogradient surface. It seems that the wettability plays important roles for cell adhesion, spreading and growth on the PLGA surface. The surface modification technique used in this study may be applicable tothe area of tissue engineering for the improvement of tissue compatibility of films- or scaffold-type substrates.

• Macromolecular Research
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• 제16권5호
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• pp.473-480
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• 2008

In this study we investigated bacterial and cell adhesion to poly(propylene carbonate) (PPC) films, that had been synthesized by the copolymerization of carbon dioxide (a global warming chemical) with propylene oxide. We also assessed the biocompatibility and biodegradability of the films in vivo, and their oxidative degradation in vitro. The bacteria adhered to the smooth, hydrophobic PPC surface after 4 h incubation. Pseudomonas aeruginosa and Enterococcus faecalis had the highest levels of adhesion, Escherichia coli and Staphylococcus aureus had the lowest levels, and Staphylococcus epidermidis was intermediate. In contrast, there was no adhesion of human cells (cell line HEp-2) to the PPC films, due to the hydrophobicity and dimensional instability of the surface. On the other hand, the PPC films exhibited good biocompatibility in the mouse subcutaneous environment. Moreover, contrary to expectation the PPC films degraded in the mouse subcutaneous environment. This is the first experimental confirmation that PPC can undergo surface erosion biodegradation in vivo. The observed biodegradability of PPC may have resulted from enzymatic hydrolysis and oxidative degradation processes. In contrast, the PPC films showed resistance to oxidative degradation in vitro. Overall, PPC revealed high affinity to bioorganisms and also good bio-degradability.

• 생명과학회지
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• 제17권10호
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• pp.1381-1386
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• 2007

황금에 대한 수 추출물의 열 변환에 의한 생리활성 변화를 보기 위하여 HPLC를 통한 peak분석과 기능성 평가를 하였다. 열처리 전의 시료 (CW)와 열처리 후의 시료 (CHW)간의 peak분석에서 CW와 CHW의 비교 시 A와 B가 없어지고 열처리 후에 C라는 다른 물질의 peak가 형성됨을 알 수 있었다. 또한, 전체적인 기능성 평가에서 항산화성에서는 CW와 CHW 별 차이가 없었고, 항고혈압 활성은 CW가 높았다. 항암성에 있어서 폐암에서는 CW가 높았고, 위암, 간암, 후두암 등에는 CHW가 높게 나왔다. 그리고, 멜라닌 생성세포의 멜라닌 생성 억제는 CHW에서 약 80%로 매우 높게 나타났다. 결론적으로 열처리를 통한 시료 내 구성성분의 변환이 기능성 차이를 보여주며, 이는 새로운 열 변환 물질의 생성 때문으로 판단된다. 이들 변화된 물질은 황금의 주성분인 Baicalin 외의 물질이 열 변환 된 것으로, 생성된 물질에 대한 구조분석이 필요한 것으로 사료된다.