• BMB Reports
• /
• 제32권4호
• /
• pp.379-384
• /
• 1999

Taxol, a natural product with significant anti-tumor activity, stabilizes microtubules and arrests cells in the G2/M phase of the cell cycle. It has been reported that taxol has additional effects on the cell such as an increase in tyrosine phosphorylation of proteins and activation of mitogen-activated protein (MAP) kinase. This phosphorylated kinase translocates into the nucleus and phosphorylates its substrate c-jun, c-fos, ATF2, and ATF3. The MAP kinase family is comprised of key regulatory proteins that control the cellular response to both proliferation and stress signals. First examination was cytotoxicity and apoptosis-induced concentration with paclitaxel in HeLa cell. A half-maximal inhibition of cell proliferation ($IC_{50}$) occurred at 13 nM paclitaxel. When DNA fragmentation was analyzed by agarose gel electrophoresis, a nucleosomal ladder became evident 24 h after a taxol (50 nM) addition to the cells. In addition, an apoptotic body was detected by electron microscopy. Taxol-treated cells were arrested at the S phase at 10 nM. Treatment of 50 nM taxol activated the extracellular signal-regulated protein kinase (ERK1), and a fraction of the activated MAP kinases entered the nucleus. It was also discovered that nucleus substrates c-jun was phosphorylated and activated in the cell. The activated ERK1 could subsequently translocate into the nucleus and phosphorylate its substrate c-jun as well. This study suggests that taxol-induced apoptosis might be related with signal transduction via MAP kinases.

• 한국축산식품학회지
• /
• 제24권2호
• /
• pp.176-181
• /
• 2004

우유내 Salmonella를 검출하기 위한 Sandwich ELISA의 특이성을 조사하였다. Sandwich ELISA에 사용한 항체들은 OMP 분획을 닭에 면역주사하여 얻은 IgY와 OMP 분획을 gel filtration하여 얻은 분자량 40,000의 OMP를 토끼에 면역 주사하여 얻은 토끼 IgG를 사용하였다. Immnoblot assay에서 IgY는 분자량 6,000의 OMP에 강하게 반응하였으며 토끼 IgG는 분자량 40,000, 35,000과 6,000의 OMP들에 강하게 반응하였다. IgY와 토끼 IgG는 Salmonella typhimurium의 다른 단백질에도 반응하였다. Competitive ELISA에서 IgY가 Salmonella의 두 개 균주에 대해 특이성을 나타냈으며 Eshcherchia coli와 Yersinia enterocolitica에 의하여서는 반응을 나타내지 않았다. 우유에 세균을 첨가하여 실시한 sandwich ELISA에서 Salmonella typhimurium 2균주가 가장 높은 흡광도를 보였다. Salmonella cholerasuis 균주들은 상대적으로 흡광도가 낮았으며 이루 일부 Salmonella cholerasuis 균주들은 비 Salmonella 균주들과 차이가 없었다.

• 대한약침학회지
• /
• 제22권4호
• /
• pp.239-247
• /
• 2019

Objectives: Allium jesdianum (Aj) is a medicinal plant that has highlighted pharmacological features. In this study, the effects of Aj extract were examined on acetaminophen (APAP)-induced hepatic failure in rats. Methods: Methanolic fraction of hydro-alcoholic extract of Aj was obtained by silica gel column chromatography method. Animals were randomly divided into four groups each containing six rats and treated by gavage as follows: the first and second groups received normal saline, the third and fourth groups were received with 50 and 100 mg/kg of Aj extract, respectively. After two consecutive weeks, the groups 2-4 were given a single dose of APAP (2 g/kg). After 48 hours, blood and liver samples were collected for biochemical and histological examinations. Results: The findings of the study demonstrated that APAP caused a significant increase in ALT (P < 0.001), AST (P < 0.001), LDH (P < 0.001), ALP (P < 0.001) serum levels, hepatic lipid peroxidation (LPO; P < 0.001) and nitric oxide (NO; P < 0.001). In this regard, APAP led to the depletion of the total antioxidant capacity (TAC; P < 0.001), glutathione and total thiol groups (TTGs; P < 0.001), and structural change in the liver. In the Aj extract groups, a considerable improvement was found in the hepatic function alongside the histopathologic changes. Conclusion: This investigation indicated that the influential effects of Aj extract in APAP-induced hepatic failure might depend on its effect on improving oxidant/antioxidant balance in hepatic tissue.

• Journal of the Korean Wood Science and Technology
• /
• 제41권4호
• /
• pp.269-275
• /
• 2013

본 연구는 유기질 문화재 보존을 위해 한국 전통 약용식물을 대상으로 항균 및 살충활성을 검증한 결과 황벽나무 열매 추출물이 우수한 활성을 나타냄을 확인하였다. 황벽나무 열매 추출물을 비극성 용매로 분획하여 그 중 가장 활성이 우수한 ethylacetate 분획물을 대상으로 실리카젤 및 Sephadex LH-20 컬럼 크로마토그래피를 실시하고 Prep-TLC를 이용하여 화합물을 순수 분리하였다. 화합물은 UV spectrum 분석 결과 260 nm 파장에서 최대흡수피크가 관찰되었고, $^1H$, $^{13}C$, HMQC, HMBC NMR과 ESI mass spectrum을 이용하여 화학구조를 분석한 결과 (4'-ethyl-2'-methylfuranyl)-6-methoxy-7-methylnona-2E,4E,6Z,8E-tetraenoic acid의 새로운 화합물임을 알 수 있었다.

• 한국환경독성학회:학술대회논문집
• /
• 한국환경독성학회 2003년도 춘계학술대회
• /
• pp.194-194
• /
• 2003

The International Agency for Research on Cancer (IARC, 1989) has classified whole diesel exhaust as probably carcinogenic to humans. Diesel exhaust particulate matter (DPM) adsorbs different chemical substances including PAHs and nitroarenes. DPM is emphasized because it is a major component of diesel exhaust, it is suspected of contributing to a health hazard. Diesel exhaust is a complex mixture of carbon particles and associated organics and inorganics, and it is not known what fraction or combination of fractions cause the health effects [cancer effects, noncancer effects (respiratory tract irritation/inflammation and changes in lung function)] that have been observed with exposure to diesel exhaust. In order to identify which chemical classes are responsible for the majority of the observed biological activities, we performed a particular biological/chemical analysis. Respirable particulate matter (PM2.5: <2.5mm) was collected from diesel engine exhaust using a high-volume sampler equipped with a cascade impactor. Particulate oganic matter was extracted by the dichloromethane/sonication method and the crude extract was fractionated according to EPA recommended procedure into seven fractions by acid-base partitioning and silica gel column chromatography. We examined genotoxic potentials of diesel exhaust particulate matter using novel genotoxicity tests, which are rapid, simple and sensitive methods for assessing DNA-damage at the DNA and chromosomal level (comet assay, in vitro MN test and Ames test). Higher genotoxic potency was observed in non polar fractions and several PAHs were detected by GC-MS, such as 1,2,5,6 dibenzanthracene, chrysene, 1,2-benzanthracene, phenanthrene and fluoranthene.

• Applied Biological Chemistry
• /
• 제48권3호
• /
• pp.263-266
• /
• 2005

춘란을 80% MeOH로 추출하고, 얻어진 추출물을 EtOAc, n-BuOH 및 $H_2O$로 용매 분획하였다. EtOAc 분획에 대하여 column chromatography를 반복하여 3종의 sterol을 분리하였다. 각각에 대하여 2D-NMR을 포함한 스펙트럼 데이터의 해석과 문헌 자료를 조사하여 ${\beta}-sitosterol$, daucosterol, ergosterol peroxide로 구조를 결정하였다. 이 화합물들은 춘란에서 이번에 처음 분리, 보고되었다.

• Applied Biological Chemistry
• /
• 제44권3호
• /
• pp.202-205
• /
• 2001

건강을 80% MeOH수용액으로 추출하고, 얻어진 추출물을 EtOAc, n-BuOH및 $H_2O$로 용매 분획하였다. 그 중에서 뚜렷한 활성을 보인 EtOAc 분획으로부터 DPPH(1-diphenyl-2-picryl hydrazyl) radical 포획법으로 항산화 활성을 추적하여 항산화 활성을 갖는 화합물 2종을 분리하였다. 각각을 NMR 및 MS 데이터의 해석과 문헌 자료를 조사하여 6-shogaol 및 12-shogaol로 구조를 결정하였다. 각 화합물의 $EC_{50}$값은 26.4 ${\mu}M$과 22.5 ${\mu}M$로 상용항산화제인 BHA, BHT 및 ${\alpha}-tocopherol$보다 뚜렷이 높은 활성을 나타내었다.

• Journal of Microbiology and Biotechnology
• /
• 제11권2호
• /
• pp.317-325
• /
• 2001

For heuristic purposes, the relative ratio of urease contents inside and outside cells was surveyed using nine ureB+ strains of Helicobacter pylori. the ratio of the enzyme specific activity appeared to vary greatly between the various H. pylori strains, ranging from 0.5 to 2.5. Besides the above compartment, urease was also richly found in the membrane fraction, especially in either peripheral or integral form. The urease distribution across the H. pylori membrane was significantly influenced by the ambient pH; the specific activity of external urease was highest at pH 5.5 with a narrow plateau, whereas the internal specific activity was highest within a pH range of 4.5 to 6.5 with a broad plateau. These finding strongly suggest that H. pylori urease is secretory and responded to the external pH. However, at pH 4.0 or below, no urease activity was detected in either the internal or external compartment, although an increase in the color development with 2,4,6-trinitrobenzene sulfonate (TNBS) was observed. Sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) demonstrated that these phenomena may be related to a specific proteolysis in certain proteins, including urease or ${\gamma}$-glutamyl transpeptidase. Interestingly, the effect of ammonium ions n alleviating the enzyme inactivation inside the H. pylori cells was remarkably similar to that of D-glucose. In addition, it would appear that the cation acted as a surrogate of not only $Na^+$ but also $K^+$ thereby increasing the H. pylori P-type ATPase activity. This is of great interest, as it implies that the urease action in H. pylori is indispensible at any locus.

• Journal of Microbiology and Biotechnology
• /
• 제11권6호
• /
• pp.986-993
• /
• 2001

Translation Initiation in prokaryotes involves the formation of a 30 S preinitiation complex, in which translation initiation factors play a role in the stimulation of fMet-tRNA (fMet) binding. However, the specific function and precise mechanism of initiation factor IF1 are still unclear. One a functionally active factor with a high purity. In the present study a large quantity of active IF was rapidly purified, obtained by the overexpression of the infA gene, and then used for a functional study. The induction of infA did not appreciably affect the growth rate of the protease-deficient strain E. coli AR68 harboring the IF1 overproducing plasmid. The level of IF1 obtained was approximately $1-2\%$ of the total cell protein, which enabled the yield of highly purified IF1 (>$98\%$ pure) to be increased to 0.15 mg of IF1/g of cells. The IF1 was isolated within one day by the centrifugatioin of the ribosomal washed fraction, by ammonium sulfate fractionation, chromatography on batch of phosphocellulose, and FPLC Mono S. The overexpressed IF1 was found to be comparable to the factor isolated from normal cells, as determined by migration in NEPHGE/SDS 2-D gels. For binding of fMet-tRNA(fMet) to the 30 S ribosomal subunitis, relatively high levels of binding were obtained when IF2 was present. The addition of IF1 up to 110 pmol proportionally stimulated the binding to a variable extent. This IF1-dependent stimulation of the 30 S preinitiation complex formation demonstrated that IF1 would appear to be exclusively essential for promoting the initiation phase of protein synthesis.

• 한국수산과학회지
• /
• 제43권4호
• /
• pp.307-313
• /
• 2010

Stanniocalcin 1 (STC1) is a glycoprotein hormone that is important in the maintenance of calcium and phosphate homeostasis in both fish and mammals. STC1 and its paralog STC2 are expressed in multiple tissues in fishes, although the physiological roles of piscine STCs are still unclear compared with those of mammals. In this study, we cloned olive flounder STC1 (ofSTC1) and ofSTC2 cDNAs into pET28a vector and used E. coli Rosetta (DE3) as the host strain for protein expression. Expression experiments were carried out using isopropyl-$\beta$-D-thiogalactoside (IPTG) and nickel affinity chromatography. We could identify the recombinant proteins as single 29.5 kDa (ofSTC1) and 33.2 kDa (ofSTC2) bands in the insoluble fraction on sodium dodecyl sulfate- polyacrylamide gel electrophoresis (SDS-PAGE). These results indicate that ofSTC1 and ofSTC2 were expressed as insoluble proteins in E. coli. Furthermore, the injection of ofSTC1 protein into juvenile tilapia resulted in a decrease of the serum calcium level. These results suggest that the purified fish STC1 and STC2 proteins may be used to elucidate the physiological role of STCs in fishes.