• EDISON SW 활용 경진대회 논문집
• /
• 제2회(2013년)
• /
• pp.273-277
• /
• 2013

We apply a density functional theory (DFT) and DFT-based non-equilibrium Green's function approach to study the electronic and transport properties of graphene nanoribbons (GNRs) co-doped with boron-nitrogen, nitrogen-phosphorus and boron-phosphorus. We analyze the structures and charge transport properties of co-doped GNRs and particularly focus on the novel effects that are absent for the single N-, B-, or P-doped GNRs. It is found that co-doped GNRs tend to be doped at the edges and the electronic structures of co-doped GNRs are very sensitive to the doping sites. Also, in case of B-N and B-P co-doped GNRs, conductance dips of single-doped GNRs disappeared with the disappearance of localized states associated with doped atoms. This may lead to a possible method of band engineering of GNRs and benefit the design of graphene electronic devices.

• 약학회지
• /
• 제40권6호
• /
• pp.713-719
• /
• 1996

Identification of soil microorganism strain B-6. a producer of acyl CoA synthetase inhibitor, based on its morphological, physiological, biochemical and chemotaxonomical charact eristics was performed. The strain B-6 was identified as Bacillus subtilis. Ihe acyl CoA synthetase inhibitor produced by this strain was highly achieved in fermentation medium that contained glucose 1.0%, soluble starch 1.0%, NH$_4$Cl 0.3%, oatmeal 1.0%, pharmamedia 1.0%, basic magnesium carbonate 0.5%. pH 7.5 at 30$^{\circ}$C for 7 days. The optimal pH and temperature for growth were 9.0 and 30$^{\circ}$C, respectively. Butanol extract of culture filterate of strain B-6 in acyl CoA synthetase inhibitor production medium containing corn steep liquor exhibited high acyl CoA synthetase inhibitor activity and antimicrobial activity against C. albicans. But chloroform extract of culture filterate of strain B-6 in medium containing NH$_4$Cl, ($NH_4)_2SO_4$ or urea instead of corn steep liquor exhibited higher antimicrobial activity against C. albicans than that of butanol extract.

• Toxicological Research
• /
• 제30권4호
• /
• pp.305-309
• /
• 2014

Recently, there has been an increase in the use of several nephrotoxicity biomarkers in preclinical experiments. In addition, it has been indicated that the result may have been influenced by secondary factors, such as sample storage condition or storage period. In this study, we have assessed the variation in urinary nephrotoxicity biomarkers as a result of urine storage conditions and storage period of the urine. Urine was sampled from specific pathogen-free Sprague-Dawley rats (19 weeks old), which were housed individually in hanged stainless steel wire mesh cages. Urine was stored at $20^{\circ}C$, at $4^{\circ}C$, or at $-70^{\circ}C$ after sampling. The levels of the biomarkers such as beta-2 microglobulin (B2M), cystatin-C (Cys-C), N-acetyl-${\beta}$-D-glucosaminidase (NAG), micro albumin (MA), micro protein (MP) were measured at 6, 24, 48 and 144 hr after sampling. The B2M level was significantly decreased at 6, 24, 48, and 144 hr compared to 0 hr at $-70^{\circ}C$ (p < 0.05, p < 0.01, p < 0.05, and p < 0.05, respectively) and 24 and 144 hr at $20^{\circ}C$ (p < 0.01, p < 0.01, respectively). The Cys-C level was significantly decreased at 144 hr compared to 0 hr at $4^{\circ}C$ (p < 0.01), at $20^{\circ}C$ (p < 0.05) and at $70^{\circ}C$ (p < 0.01). MP and MA levels were not different for 144 hr in all storage conditions. Taken together, B2M and Cys-C levels were modulated by storage temperature and period. For the enhancement of test accuracy, it is suggested that strict protocols be established for samples to minimize the effects of the storage conditions on the detected levels of biomarkers.

• Journal of Microbiology
• /
• 제40권3호
• /
• pp.211-218
• /
• 2002

A 4.8-kb DNA fragment encoding the P-450 type hydroxylase and ferredoxin genes was cloned from Pseudonocardia autotrophica IFO 12743 that can convert vitamin D$\_$3/ into its hydroxylated active forms. In order to isolate the P-450 gene cluster in this organism, we designed PCR primers on the basis of the regions of an oxygen binding site and a heme ligand pocket that are general characteristics of the P-450 hydroxylase. Sequencing analysis of the BamHI fragment revealed the presence of four complete and one incomplete ORFs, named PauA, PauB, PauC, and PauD, respectively. As a result of computer-based analyses, PauA and PauB have homology with enoyl-CoA hydratase from several organisms and the positive regulators belonging to the tetR family, respectively. PauC and PauD show similarity with SuaB/C proteins and ferredoxins, respectively, which are composed of P-450 monooxygenase systems for metabolizing two sulfonylurea herbicides in Streptomyces griseolus PauC shows the highest similarity with another CytP-450$\_$Sca2/ protein that is responsible for production of a specific HMG-CoA reductase inhibitor, pravastatin, in S. carbophilus. Cultures of Steptomyces lividans transformant, containing the P-450 gene cluster on the pWHM3 plasmid, was unable to convert vitamin D$\_$3/ to its hydroxylated forms.

• 한국버섯학회지
• /
• 제18권3호
• /
• pp.208-213
• /
• 2020

양송이배지로부터 분리한 인산가용화균 Burkholderia contaminans PSB-A와 Burkholderia ambifaria PSB-B의 단일접종 및 동시접종에 따른 인산가용화 능력의 시너지 효과 및 상추생육효과를 조사하였다. 인산캄슘이 함유된 NBRIP 액체배지에 분리균을 접종하고 해리된 가용인산(soluble phosphorus)함량을 HPLC에 의해 분석하여 인산가용화능을 측정한 결과, 배양 3일차에 동시접종구 166.3 ㎍ mL^-1, B. contaminans 143.7 ㎍ mL^-1, B. ambifaria 127.1 ㎍ mL^-1의 순으로 나타나 두 종의 인산가용화세균간의 동시접종에 의한 시너지효과가 다소 관찰되었다. 배지 내 pH 와 잔류 glucose 함량 변화도 모든 접종구에서 배양 1 - 3일 후 pH 7.0에서 pH 4.0 수준으로 감소하였으며, glucose 함량은 초기 10 mg mL^-1 에서 4.3 mg mL^-1 수준으로 검출되어 인산가용화능과 거의 유사한 경향을 보였다. 배양여액의 유기산 분석결과 gluconic acid 약 12.3 mg mL^-1 와 malic acid 약 7.9 mg mL^-1 수준으로 가장 높게 검출되었으며, 결과적으로 두 세균이 분비하는 유기산이 배지의 pH를 감소시키고, 인산 가용화를 유도하는 주요 원인임을 확인할 수 있었다. 접종 4주 후 상추 생육차이를 조사한 결과, TCP를 첨가하지 않은 B. contaminans 접종구, B. ambifaria 접종구 와 동시 접종구에 비해 TCA 첨가한 모든 처리구에서 약 7-9% 수준의 생육증진효과가 보였으나, 단일접종과 동시접종구간에 유의수준의 차이를 확인할 수 없었다.

• Bulletin of the Korean Chemical Society
• /
• 제9권6호
• /
• pp.349-352
• /
• 1988

[(Benzene)Mn$(CO)_3$]$^+$ reacts with NaP(O) (OR)$_2$ (R = Me, Et, Ph) to give the phosphonate compound 1. Compound 1 reacts with R'Li (R = Me, Ph, $^nBu, ^tBu$) to yield the isomerized compound 2 and the alkylated compound 3. [(Toluene)Mn$(CO)_3$]$^+$ reacts with NaP(O)$(OMe)_2$ to give the phosphonate complexes 1-A and 1-B. Treatment of 1-A with $^tBuLi$ in THF affords complexes 3-A and 3-B with the later major. With 1-B only the complex 3-C is formed. [(Anisole)Mn$(CO)_3$]$^+$ reacts with NaP(O)$(OMe)_2$ to give the phosphate complex 1-C, which on treatment with $^tBuLi$ and then $H_2O$ yields compound 3-D. After demetallation of compound 3-D, meta-tertbutyl-anisole is obtained in a reasonable yield.

• 자연과학논문집
• /
• 제16권1호
• /
• pp.15-29
• /
• 2005

내열성의 cyclomaltodextrin glucanotransferase (CGTase)를 이용하여 열에 안정한 싸이클린 텍스트린 (CD)을 생산하기 위하여 매우 높은 CGTase 활성을 보이는 고열성이며 호알카리성인 B-13세균을 분리하여 형태적, 생리학적 특성과 16S 리보솜 RNA 서열분석 등을 통하여 Bacillus cereus B-13으로 동정하였다. Bacillus cereus B-13 2% 가용성 전분, 1% 효모 추출물, 1% $Na_2CO_3$ 등을 함유하는 SYC 배지 (pH 8.5)에 접종하여 $50^{\circ}C$에서 24시간 배양하였을 때 최고의 CGTase 활성(130 U/ml)을 보였다. 또한 부분 정제된 CGTase의 작용 최적 온도와 pH는 각각 $60^{\circ}C$, pH 8.5-9.0 이었고 $80^{\circ}C$이하와 pH5.0-10.0에서 안정하였다. 1% 가용성 전분을 부분 정제한 CGTase와 작용시켰을 때 49%의 CD 수율을 보였다.

• Journal of Korean Neurosurgical Society
• /
• 제49권1호
• /
• pp.13-19
• /
• 2011

Objective: The purpose of this study is to investigate the combined effects of ginkgo biloba extract, ginkgolide A and B and aspirin on SK-N-MC, human neuroblastoma cell viability and mRNA expression of growth associated protein43 (GAP43), Microtubule-associated protein 2 (MAP2), B-cell lymphoma2 (Bcl2) and protein53 (p53) gene in hypoxia and reperfusion condition. Methods: SK-N-MC cells were cultured with Dulbecco's Modified Eagle's Medium (DMEM) media in $37^{\circ}C$, 5% $CO_2$ incubator. The cells were cultured for 8 hours in non-glucose media and hypoxic condition and for 12 hours in normal media and $O_2$ concentration. Cell survival rate was measured with Cell Counting Kit-8 (CCK-8) reagent assay. Reverse transcriptase polymerase chain reaction (RT-PCR) was used to estimate mRNA levels of GAP43, MAP2, Bcl2, and p53 genes. Results: The ginkgolide A and B increased viable cell number decreased in hypoxic and reperfused condition. The co-treatment of ginkgolide B with aspirin also increased the number of viable cells, however, there was no additive effect. Although there was no increase of mRNA expression of GAP43, MAP2, and Bcl2 in SK-N-MC cells with individual treatment of ginkgolide A, B or aspirin in hypoxic and reperfused condition, the co-treatment of ginkgolide A or B with aspirin significantly increased GAP43 and Bcl2 mRNA levels. In MAP2, only the co-treatment of ginkgolide A and aspirin showed increasing effect. The mRNA expression of p53 had no change in all treating conditions. Conclusion: This study suggests that the combined treatments of Ginkgo biloba extracts and aspirin increase the regeneration of neuroblastoma cells injured by hypoxia and reperfusion.

• Journal of Nutrition and Health
• /
• 제25권5호
• /
• pp.351-359
• /
• 1992

This study was conducted to compare the effects of perilla oil or corn oil on lipid peroxidation and eicosanoid productions which are associated with the promotion of carcinogenesis. in liver or blood in rats. Male Sprague-Dawley8 weaning rats were fed on semisynthetic diets containing 15%(w/w) beef fat(BF). corn oil(CO) or perilla oil(PO) Three weeks after the half of rats in each diet group were injected with a single dose of 50mg 2-acetylaminofluorene (AAF)/Kg BW hepatocarcinogen intraperitoneally 3 times at 2-day interval and all of the rats were sacrificed after 8 weeks from the first injection. The rats fed on different dietary fats without 2-AAF treatment had not different MDA produc-tion and conjugated diene content in liver microsome. CO+AAf group had significantly higher conjugated diene content than BF+AAF and PO+AAF groups. and lower glucose-6-phospha-tase activity than BF+AAF group But PO+AAF had similar conjugated diene content to BF+AAF group and significantly lower MDA production than BF+AAF and CO+AAF groups. The hepatic mocrosomal lipid peroxidation was slightly greater in CO group than in PO group though perilla oil(P/S=9.67) has much more polyunsaturated fatty acids than corn oil(P/S=2.92) PG E2 level in liver and TX B2 level in plasma were significantly higher in CO group than in BF and PO groups. TX B2 level was lowered in CO and BF groups by 2-AAF treatment. These results reach to the contclousion than the type of dietary fatty acid as well as the P/S ratio has effect on hepatic microsomal lipid peroxidation and eicosanoid production and perilla oil or linolenic acid(n3) might be less effective on lipid peroxidation or PG E2 and TX B2 mediated tumor promotion than corn oil or linoleic acid(n6).

• 농약과학회지
• /
• 제10권1호
• /
• pp.7-14
• /
• 2006

새로운 5-benzofuryl-2-[1-(alkoxyimino)alkyl]-3-hydroxycyclohex-2-en-1-one 유도체들의 3차원적인 정량적 구조와 발아 전, 벼(Oryza sativa L.)와 논피(Echinochloa crus-galli)에 대한 제초활성과의 관계를 비교분자 유사성 지수분석(CoMSIA) 방법으로 연구하였다. 가장 양호한 CoMSIA 모델로서 벼에 대한 A5 모델($r^2_{cv.}=0.569$ 및 $r^2_{ncv.}=0.941$)은 주로 소수성장(39.7%)과 입체장(31.6%) 그리고 논피에 대한 B4 모델($r^2_{cv.}=0.595$ 및 $r^2_{ncv.}=0.933$)은 정전기장(46.7%)과 수소결합 받게장(30.8%)에 각각 의존적이었다. B4 모델에 의하여 예측된 $R_1=SF_5,\;R_2=R_3=R_4=H(P1)$ 치환체(벼: $pI_{50}=4.84$ 및 논피: $pI_{50}=7.21$, ${\Delta}pI_{50}=2.37$)는 논피에 대하여 가장 높은 제초활성을 나타내었으며 두 초종 간 선택성이 가장 큰 치환체이었다.