• Bulletin of the Korean Chemical Society
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• 제28권4호
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• pp.596-600
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• 2007

The structures and energies of p-tert-butylcalix[5]crown-6-ether (1) and its alkylammonium complexes have been calculated by DFT B3LYP/6-31G(d,p) method. We have studied the binding sites of these host-guest complexes focusing on the p-tert-butylcalix[5]arene pocket (endo) or the crown-6-ether moiety (exo) of 1. The smaller alkylammonium cations have the better complexation efficiency with p-tert-butylcalix[5]crown-6- ether than the bulkier alkylammonium ions. For the sec- and tert-butylammonium ions, the hydrogen-bond distances of the exo-complexes are shorter, therefore, stronger than the endo-cases. This DFT calculated result is in parallel with the trend of the experimental association constants of the branched butylammonium ions.

• Mycobiology
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• 제35권3호
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• pp.145-149
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• 2007

The Elfvingia applanata (EA), Hericium erinaceum (HE), Grifola frondosa (GF), Pholiota nameko (PN), Pleurotus eryngii (PE), Trametes suaveolens (TS), Fomes fomentarius (FF), and Inonotus obliquus (IO) could produce the endo- (EN) and exo-biopolymer (EX) in submerged culture. The highest anti-complementary activity of the EN was exhibited by PN (49.1%), followed by HE (38.6%), TS (37.0%), and FF (33.0%), whereas the high activity of the EX was found with GF (59.8%), followed by HE (36.3%), TS (30.8%), and IO (28.8%). The EN of P. nameko (EN-PN) and EX of G. frondosa (EX-GF) were found to contain 78.6% and 41.2% carbohydrates, while 21.4% and 58.8% protein, respectively. The sugar and amino acid compositions of EN-PN and EX-GF were also analyzed in detail.

• 한국산학기술학회:학술대회논문집
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• 한국산학기술학회 2008년도 추계학술발표논문집
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• pp.339-342
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• 2008

Methacrylate와 Cyclopentadiene을 반응하여 5-methylbicyclo[2.2.1]hept-2-ene-5-carboxylate (MBHC)를 합성하고 만들어진 MBHC를 Column Chromatography를 이용하여 Endo와 Exo를 분리하였고, MBHC에 붙는 작용기에 따른 수율 및 Endo, Exo의 비율을 확인하였다.

• 한국산학기술학회:학술대회논문집
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• 한국산학기술학회 2011년도 춘계학술논문집 1부
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• pp.493-495
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• 2011

cyclohexyl methacrylate와 cyclopentadiene을 반응하여 cyclohexyl 5-methylbicyclo[2,2,1]hept-2-ene-5-carboxylate를 합성하고 합성된 Norbornene계 화합물을 GC를 이용하여 그 비율을 측정하였고 Column Chromatography를 이용하여 endo와 exo를 분리해 $^1H-NMR$을 이용하여 endo와 exo 화합물의 구조를 확인하였다.

• 한국미생물·생명공학회지
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• 제20권1호
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• pp.20-24
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• 1992

Inulinase의 효율적인 재사용을 위하여 vinylsulfone activated agarose에 endo- 및 exoinulinase를 고정화시켰다. Gram gel당 exoinulinase는 400U, endoinulinase는 80U까지 고정화시킬 수가 있었고 열안정성은 exoinulinase 에서 증가되었다. 두 고정화 효소의 혼합비율에 따른 synergistic effect는 endo/exo가 0.5-0.1일 대 가장 컸으며, synergistic effect는 혼합되지 않은 상태의 고정화 효소에 비해 그 활성이 약 1.7배 증가하였다. 두 고정화 효소의 최적 pH는 4.4-5.0 범위이었으며 operational stability는 batch reactor에서 20번 반복된 실험결과 어떠한 효소활성의 감소도 보이지 않았다.

• 한국균학회지
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• 제19권2호
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• pp.143-147
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• 1991

사과겹무늬썩음병균 Botryosphaeria dothidea를 pectin-polypectate 배지(培地)와 사과배지(培地)에 배양(培養)하여 pectin질(質) 분해효소(分解酵素)의 생산(生産)과 활성(活性)을 조사하였다. exo-polygalacturonase와 exo-polymethylgalacturonase의 활성은 사과배지에서 배양 6일에 각각 6.4 와 7.2 units로 최대의 활성을 나타내었고, 인공배지에서는 배양 8일에 각각 5.9 와 5.3 units 의 활성을 나타내었으나 사과배지에 비해 낮았다. endo-polygalactu-ronase와 endo- polymethylgalacturonase는 인공배지에서 각각 4.4 와 16.2 units로 배양 8 일과 10일에서 최대활성을 나타내었으나 사과배지에서는 배양 8일에 각각 3.2와 6.7 units로 낮은 활성을 보였다. pecti-nmethyl-trans-eliminase와 polygalacturonate-trans-eliminase의 활성은 사과배지보다 인공배지에서 높게 나타났으며, 균 생장은 인공배지와 사과배지에서 각각 배양 6일과 8일에 최고의 생장을 나타내었다.

• Bulletin of the Korean Chemical Society
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• 제28권11호
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• pp.2041-2044
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• 2007

The reactions of mercury(II) chloride with O3S2-donor macrocyclic ligands with (L1) and without (L2) dibenzosubunit afforded respective exo- (1) and endo-coordinated (2) complexes depending on the ring rigidity of the ligands. From the X-ray crystal structures and comparative NMR studies for the complexes 1 and 2, it is confirmed that the resulting species with different coordination modes exist not only in solid state but also in solution state.

• Journal of Microbiology and Biotechnology
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• 제12권6호
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• pp.872-877
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• 2002

The hypolipidemic effect of the exe-biopolymer (EXBP) and endo-biopolymer (ENBP) produced from a submerged mycelial culture of Ganoderma lucidum was investigated in dietary-induced hyperlipidemic rats. Hypolipidemic effects were achieved in both the EXBP- and ENBP-treated groups, however, the former proved to be more potent than the latter. The administration of the EXBP (100 mg/kg body weight) substantially reduced the plasma total cholesterol, low-density lipoprotein (LDL) cholesterol, triglyceride, phospholipid levels, and atherogenic index by 31.0, 39.0, 35.4, 28.1, and 53.5%, respectively, when compared to the control group. The EXBP also lowered the liver total cholesterol, triglyceride, and phospholipid levels by 22.4, 23.1, and 12.9%, respectively. Furthermore, the high-density lipoprotein (HDL) cholesterol and ratio of HDL cholesterol to total cholesterol were significantly increased by as much as 24.2% and 47.6%, respectively.

• 한국산학기술학회:학술대회논문집
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• 한국산학기술학회 2004년도 추계학술대회
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• pp.265-268
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• 2004

Methyl methacrlate와 cyclopentadiene을 반응하여 Methyl 5-methylbicyclo(2.2.1)hept-2-ene-5-carboxylate(MMBHC)를 합성코자 하였다. 합성된 MMBHC의 온도, solvent 변화와 촉매($AlCl_3$)의 사용 유무에 따른 endo, exe의 비율을 관찰하였다. 온도가 낮은 경우 온도가 높은 쪽 보다 endo 비율이 높았고 촉매($AlCl_3$)를 사용하였을 때(약 endo : exo = 63 : 37) 촉매를 사용하지 않은 반응(endo : exe = 34 : 66)보다 endo의 비율이 높았다. methyl acrylate를 사용한 경우 같은 조건에서 endo : exe의 비율이 93.5 : 6.5로 MMA를 사용한 경우보다 endo의 비율은 좋았다. 온도가 높은 경우 수율은 좋았지만 exe의 비율이 높았고 solvent에 따라 endo, exe의 선택도는 큰 차이를 보이지 않음을 알 수 있었다.

• Bulletin of the Korean Chemical Society
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• 제33권10호
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• pp.3321-3330
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• 2012

The complexation characteristics of mixed [2 + 2'] calix[4]aryl derivatives (3 and 4) with alkali metal cations were investigated by the mPW1PW91 (hybrid HF-DF) calculation method. The total electronic and Gibbs free energies of the various complexes (cone, partial-cone, 1,2-alternate, and 1,3-alternate) of sodium and potassium cations with 3 and 4 were analyzed and compared. The structures of the endo- or exo-complexes of the alkali metal cation with the host 3 were optimized using the mPW1PW91/6-31G(d) method, followed by mPW1PW91/6-311+G(d) calculations. The structures of the endo- or exo-complexes of the alkali metal cation with the host 4 were optimized using the mPW1PW91/6-31G(d,p) method. The mPW1PW91 calculated relative energies of the various conformations of the free hosts (3 and 4) suggest that the cone conformers of 3 and 4 are the most stable. The mPW1PW91calculations also suggest that the complexation efficiencies of the sodium ion with hosts 3 and 4 are about 24 and 27 kcal/mol better than those of the potassium ion, respectively. These trends are in good agreement with the experimental results. The exo-complexation efficiencies of the sodium ion toward the conformers of hosts 3 and 4 are roughly 14 and 17 kcal/mol better than those for the endo-$Na^+$-complexes of 3 and 4, respectively. The exo-complexation of the cone isomer of 3 with cation could be confirmed by the differences of the diagnostic C=O bands in the free host and its complex's IR spectra.