• BMB Reports
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• v.34 no.1
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• pp.90-94
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• 2001

The mutagenic activity of chitosan oligosaccharide and its antimutagenic effect against 2-amino-3,8-dimethylimidazo[4,5-f]quinoxaline (MeIQx) were investigated using the Salmonella/Ames test. No mutagenic activity was found in the Salmonella typhimurium strains TA 98 and TA 100, either with or without S9 activation. In contrast, chitosan oligosaccharide showed an inhibitory effect on the mutagenic activity of the cooked food mutagen, MeIQx, in the presence of S9. The influence of chitosan oligosaccharide on the genotoxicity of MeIQx was examined using a host-mediated assay in mice. The oligosaccharide was administered for 14 consecutive days (intragastric application at doses of 0.1 or 0.5 g/kg body wt) to mice. S. typhimurium TA 98 was given intravenously before an oral dose of MeIQx (4.5 mg/kg body wt.). The number of $his^+$ revertants were determined from the Ever of mice. The intragastric application of oligosaccharide led to a 47% reduction in the number of mutants induced by MeIQx (p<0.05). These results suggested that chitosan oligosaccharide had antimutagenic properties against MeIQx in vitro and in vivo.

• Microbiology and Biotechnology Letters
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• v.20 no.5
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• pp.498-504
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• 1992

In order to investigate the antimutagenicity of the sweet potato enzymatic browning reaction products (SPEBRP) were studied the DNA breaking action, spore rec assay and Ames test. In the DNA breaking action of reaction mixture of SPEBRP and polyphenol compounds with an agarose horizonal electrophoresis, catechol (CAT)-SPEBRP and hydroxyhydroquinone (HHQ)SPEBRP inhibited DNA breaking effect in the presence of $Fe^{2+}$. In the spore ree assay using Bacillus subtilis H17(rec+) and M45(rec-), 3,4-dihydroxytoluene (DHT)-SPEBRP showed strong antimutagenic effects on MNNG. In the Ames test using Salmonella tYPhimurium TA 98 and TA 100, pyrogallol(PYR)-, 3,4-dihydroxytoluene (DHT)- and hydroxyhydroquinone (HHQ)-SPEBRPs suppressed about 67%, 71% and 63% in the mutagenesis induced by Benzo($\alpha$)Pyrene(B($\alpha$)p).

• Bulletin of the Korean Chemical Society
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• v.28 no.9
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• pp.1463-1466
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• 2007

Single phases of multi-component oxides films, ZrTiO4 and Ta2Zr6O17, could be synthesized by using the combinatorial approach through surface sol-gel route, coating the appropriate mole ratio of 100 mM zirconium butoxide, tantalum butoxide and titanium butoxide precursors on Pt/Ti/SiO2/Si (100) substrate, following pyrolysis at 450 oC, and annealing them at 770 oC. Both the films and bulks of ZrTiO4 and Ta2Zr6O17 showed very stable dielectric properties in temperature range, ?140 to 60 oC, and frequency range, 100 Hz to 1 MHz, promising their applications in wide range of temperatures and frequencies. The dielectric constants of the films were lower and a little more dependent on frequency than those of the bulks. The reduction of dielectric property in the film was mainly due to the interfacial effects that worked as series and parallel-connected capacitances toward the substantial film capacitance.

• Journal of the East Asian Society of Dietary Life
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• v.11 no.1
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• pp.19-25
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• 2001

This study was performed to examine the antimutagenic and cytotoxic effects of potato vinegar and commercial vinegars(cider, brown rice, persimmon vinegars) on Salmonella typhimurium TA98, TA100 and cancer cell lines using Ames test and cytotoxicity assay, respectively. In Ames test, all vinegars did notexhibit any mutagenicity , but showed substantial inhibitory effects against N- methyl - N -nitro - N- nitrosog -uanidine(MNNG) , 4-nitroquinoline-1-oxide(4NQO), 3-amino-1,4-dimethyl-5H-pyrido(4,3-b)indol(Trp-P-1)and benzo( $\alpha$ )pyrene(B( $\alpha$ )P). The number of revertants per plate decreased significantly when these vinegars(80 ug/plate) were added to the assay system using TA100 strain. Especially, potato vinegar(80 ug/plate) showed high inhibition rate of 69.9% against mutagenicity of B( $\alpha$ )P on TA100 strain. In the cytotoxicity assay, these vinegars also showed prominent cytotoxic activity against human cancer cell lines. Potato vinegar(10 ug/well) showed the strongest cytotoxic effect against HT1080 (fibrosacoma cell) andK562 ( myelogenous leukemia) at the same concentration when compared with other vinegars.

• KSBB Journal
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• v.9 no.4
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• pp.400-405
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• 1994

The conditions for ${\beta}$-galactosidase production from alkalophilic, thermophilic Bacillus sp. TA-11 were investigated. The maximal enzyme production was obtained when the strain was cultured at $50^{\circ}C$ for 5 days with fed-batch culture in the optimal medium containing 1.5% lactose, 0.6% yeast extract 0.15% $K_2HP0_4$and initial pH 9.5, and then final enzyme activity under the above conditions was 5200 unit/ml of cell free extract.

• Journal of the Microelectronics and Packaging Society
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• v.2 no.2
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• pp.31-40
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• 1995

Donor dopant로 WO3, Ta2O5 및 Nb2O5를 첨가한 Zr0.8Sn0.2TiO4 세라믹스의 유전상수 $\varepsilon$r 품 질계수 Q 및 공진주파수의 온도계수 rf에 대하여 연구하였다. 139$0^{\circ}C$에서 32시간 소결시 donor dopant 첨가량에 따른 ZST의 유전상수는 소결밀도의 변화 거동과 잘 일치하였다. 5.5 GHz에서 측정 한 ZST의 품질계수 Q는 ~0.5 mol% WO3 Ta2O5 및 Nb2O5 첨가에 의해 6800에서 8500 정도로 증가 하였다. ZST의 $\tau$f는 0.3 mol%까지의 WO3 첨가량 증가에 따라 0 ppm/$^{\circ}C$에서 -4.6 ppm/$^{\circ}C$까지 음 의 값으로 직선적으로 감소하였으며 0.4 mol% 범위의 Ta2O5 및 Nb2O5 첨가에 의해 -7 ppm/$^{\circ}C$ 까지 직선적으로 감소하였다.

• Korean Journal of Materials Research
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• v.4 no.8
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• pp.855-860
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• 1994

Ta-silicide films in polycide structure were prepared by rapid thermal annealing of sputtered Ta film on poly-Si and doped poly-Si. Effects of phosphorus on Ta-silicide formation were investigated. Independent of the ion dose($1 \times 10^{13}\to 5 \times 10^{15}$/ions/$\textrm{cm}^2$), Ta-silicide phases were formed at $800^{\circ}C$ and stabilized above $1000^{\circ}C$. From the result of XRD at $800^{\circ}C$ and $900^{\circ}C$, however, it was indicated that the more the doping concentration the weaker the intensity of Ta-silicide phases. Furthermore, the observation of SEM revealed that the increase of the doping concentration retarded silicidation. As the temperature increased, the dopant effect was weakened gradually and almost disappeared at $1000^{\circ}C$. Therefore the variation of the ion dose from ($1 \times 10^{13}\to 5 \times 10^{15}$/ions/$\textrm{cm}^2$) did not greatly affect the formation of Ta-silicide at high temperatures but retarded slightly the silicidation at low temperatures.

• Journal of Physiology & Pathology in Korean Medicine
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• v.24 no.6
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• pp.1012-1018
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• 2010

This study investigated the functional effect by diets of Triticum aestivum sprout (TA) on the levels of blood glucose and lipid profiles in streptozotocin(STZ)-induced diabetic mice. Diabetes mellitus were induced by STZ intraperitoneal injection (50 mg/kg) into the male Balb/c mice. All mice fed AIN-93 diet for 3 weeks. Mice were divided to 4 groups: normal, diabetic control and two experimental groups (TA 5.0, diet with Triticum aestivum sprout 5.0% w/w; TA 2.5, diet with Triticum aestivum 2.5% w/w). The blood glucose level was decreased by TA intake in diabetic mice in the dose-dependant manner; 21.34% and 35.77% in TA 2.5 and TA 5.0 groups. The weight gain and feed efficiency ratio also were improved by TA intake compared with DM group. The weight gain was increased 1.28 and 1.09 folds in TA 5.0 and TA 2.5 groups, respectively. The weight of organs, including liver and kidney, was reduced but that of spleen and abdominal fat was increased by TA intake. Moreover, TA treatment increased the level of HDL but decreased the level of total cholesterol and triglycerides in the blood of diabetic mice. The blood of HbA1c also was significantly decreased without changing hematocrit by TA treatment compared with DM group. These results indicate the TA intake has the functional effects attenuating blood glucose and plasma lipid levels in insulin-dependent diabetes.

• Economic and Environmental Geology
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• v.46 no.5
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• pp.455-468
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• 2013

We performed reconnaissance survey on Dashinchilen Nb-Ta REE area and Sant Cu area which are located in southeastern part of Khangai rare metals mineralized belt. In Dashinchilen area, Nb and Ta have been found in pegmatitic granite that is largely distributed in the survey area and muscovite in pegmatite which is an intrusion in paleozoic sedimentary rocks which are mostly composed of sandstone. While grades of Nb and Ta are not high, an outcrop that has high Th and U contents (542 ppm of Th and 56.9 ppm of U) has been found. Average and maximum REE contents in the survey area is three times and seven times, respectively, larger than average REE contents in the crust of the Earth. In Sant area, copper oxides such as malachite has been found in quartzite in paleozoic sedimentary rocks. A sedimentary rock formation that has high grade of Mn (12.4-34.6 %) has been found in the survey area. This sedimentary rock formation is the same formation with that of Ugii Nuur Fe-Mn mineralization which is located about 200 km northwest of the survey area. Average and maximum REE contents in the survey area is two and half times and seven times, respectively, larger than average REE contents in the crust of the Earth. According to the factor analysis for the data of the geochemical analysis, Nb and Ta in Dashinchilen area are highly correlated with muscovite and Cu in Sant area is highly correlated with Mo, Sn, and Bi. Furthermore, the factor analysis results show that Fe in Sant area was deposited with rare earth elements.

• Journal of the Korean Society of Food Science and Nutrition
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• v.25 no.6
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• pp.1062-1068
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• 1996

This study was Performed to determine the effects of antimutagenicity and anticancer of Taxus cuspidata produced in Korea. Extracts of Taxus cuspidata were obtained from leaves, barks and roots. All the samples tested had no effects on the mutagenicity by Ames test using Salmonella typhimurium TA98 and TA100 or rec-assay using Bacillus subtilis Hl7 and M45 strains. However the treatment of 50$\mu\textrm{g}$/plate of Taxus cuspidata extracts showed strong antimutagenicity with 98% inhibition against TA100 induced by MNNG and with 98% inhibition against TA98 and TA100 induced by 4NQO whereas 73~89% and 16~60% antimutagenic effect were shown against both strain induced by Trp-P-1 and $Benzo(\alpha)pyrene,$ respectively. The treatment of $0.5$\mu\textrm{g}$/{\mu}\ell$ root extracts had the highest cytotoxicity with 90% against liver cancer cell, Hep 3B, followed by bark extracts(87%) and leave extracts(72%), whereas $0.5$\mu\textrm{g}$/{\mu}\ell$ treatment of Taxus cuspidata extract had only 22~36% cytotoxicity on human normal liver cell WRL 68.