• Bulletin of the Korean Chemical Society
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• 제31권5호
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• pp.1314-1318
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• 2010

The $[Ru(tpy)_2]Cl_2$ (tpy:2,2':6',2"-terpyridine) complex was synthesized and its structure was confirmed by $^1H$-NMR and elemental analysis. Its binding mode toward DNA was compared with the well-known $[Ru(bpy)_3]Cl_2$ (bpy:2,2-bipyridyl), using isotropic absorption, linear dichroism(LD) spectroscopy, and an energy minimization study. Compared to $[Ru(bpy)_3]^{2+}$, the $[Ru(tpy)_2]^{2+}$ complex exhibited very little change in its absorption pattern, especially in the MLCT band, upon binding to DNA. Furthermore, upon DNA binding, both Ru(II) complexes induced a decrease in the LD magnitude in the DNA absorption region. The $[Ru(tpy)_2]^{2+}$ complex produced a strong positive LD signal in the ligand absorption region, which is in contrast with the $[Ru(bpy)_3]^{2+}$ complex. Observed spectral properties led to the conclusion that the interaction between the ligands and DNA bases is negligible for the $[Ru(tpy)_2]^{2+}$ complex, although it formed an adduct with DNA. This conclusion implies that both complexes bind to the surface of DNA, most likely to negatively charged phosphate groups via a simple electrostatic interaction, thereby orienting to exhibit the LD signal. The energy minimization calculation also supported this conclusion.

• 한국미생물·생명공학회지
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• 제31권1호
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• pp.90-93
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• 2003

The antibacterial activity of chitosan-alginate-Fe(II) complex (CAFC) against Escherichia coli and Staphylococcus aureus, and an opportunistic pathogen, Candida albicans, was investigated. A concentration of 1 mg/1 was needed to inhibit the growth of S. aureus and E. coli, while 100 mg/liter was sufficient for the growth inhibition of Candida albicans. The ion leakage of potassium and phosphate from E. coli cell and the penetration of ethidium bromide dye into it indicate that CAFC might be able to increase the cell permeability and consequently cellular leakage, thus leading to cell plasmolysis. Scanning electronmicroscope showed that E. coli cells treated with CAFC became irregular, swelling and expanded. In a field trial, control piglets showed average mortality of up to 60% within 3 days after the onset of diarrhea. In contrast, CAFC-treated groups without mortality was decreased to average 56% on the 1 st day after the treatment, and average 7% on the 3rd day. After then, piglets with diarrhea was not found.

• 한국응용과학기술학회지
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• 제32권3호
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• pp.451-460
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• 2015

An enantioselective recognition of D- and L-tryptophan (Trp)-b-cyclodextrin (CD) inclusion complex was performed using electrochemical and FT-Raman spectroscopic analysis. From the electrochemical analysis, the selectivity coefficient ($K_{DL}$) of b-CD inclusion complexes was found higher than that of the D- and L-Trp in phosphate buffered saline (PBS, pH=7.0) solution. The percentage of enantioselectivity ($I_{%{ee}}$) for peak current of D-Trp-b-CD inclusion complexes was observed higher than that of L-Trp-b-CD inclusion complexes in PBS solution. From Raman spectroscopy, chemical shift difference (D, $cm^{-1}$) for the C=C stretch, ring vibration, and ring breathing of D-Try-b-CD inclusion complex were observed higher than that of L-Trp-b-CD inclusion complex. The electrochemical and Raman spectroscopic analyses were found very useful for chiral detection of racemic amino acid in the presence of b-CD.

• Bulletin of the Korean Chemical Society
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• 제34권10호
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• pp.2895-2899
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• 2013

Direction of intercalation to DNA of the planar dipyrido[3,2-a:2',3'-c]phenazine ligands (dppz) of a bis-Ru(II) complex namely, $[Ru(1,10-phenanthroline)_2dipyrido[3,2-a:2^{\prime},3^{\prime}-c]phenazine]^{2+}$ linkered by a 1,3-bis(4-pyridyl)propane, was investigated by probing the behavior of 4',6-diamidino-2-phenylindole (DAPI) that bound deep in the minor groove. Bis-intercalation of DPPZ resulted in a little blue shift and hyperchromism in DAPI absorption band, and a large decrease in DAPI fluorescence intensity which accompined by an increase in the dppz emission intensity. Diminishing the intenisty of the positive induced circular dichroism (CD) and linear dichroism (LD) were also observed. These spectral changes indicated that insertion of dppz ligand caused the change of the binding mode of DAPI, which probably moved to the exterior of DNA from the minor groove and interacted with the phospghate groups of DNA by electrostatic interaction. At the surface of DNA, DAPI binds at the phosphate groups of DNA by electrostatic attraction. Consequently, this observation indicated that the dppz ligand intercalated from the minor groove.

• 한국결정학회:학술대회논문집
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• 한국결정학회 2003년도 춘계학술연구발표회
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• pp.17-17
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• 2003

tRNA (m¹ G37) methyltransferase (TrmD) catalyze s the trans for of a methyl group from S-adenosyl-L-methionine (AdoMet) to G/sup 37/ within a subset of bacterial tRNA species, which have a residue G at 36th position. The modified guanosine is adjacent to and 3' of the anticodon and is essential for the maintenance of the correct reading frame during translation. We have determined the first crystal structure of TrmD from Haemophilus influenzae, as a binary complex with either AdoMet or S-adenosyl-L-homocysteine (AdoHcy), as a ternary complex with AdoHcy/phosphate, and as an apo form. The structure indicates that TrmD functions as a dimer (Figure 1). It also suggests the binding mode of G/sup 36/G/sup 37/ in the active site of TrmD and catalytic mechanism. The N-terminal domain has a trefoil knot, in which AdoMet or AdoHcy is bound in a novel, bent conformation. The C-terminal domain shows a structural similarity to DNA binding domain of trp or tot repressor. We propose a plausible model for the TrmD₂-tRNA₂ complex, which provides insights into recognition of the general tRNA structure by TrmD (Figure 2).

• Archives of Pharmacal Research
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• 제19권6호
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• pp.435-440
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• 1996

The effect of benzalkonium chloride on skin permeability of partially modified antisense phosphorothioate oligonucleotides (PS-ODN), which are designed as scar formation inhibitor, was investigated using Franz Diffusion Cell. When the concentration ratio of PS-ODN-quarternary ammonium salt complex is more than 1:100, the apparent partition coefficient (APC) of each complex was increased in the following order; tetraphenyl phosphonium chloride (TPP) < cetyltrimethyl ammonium bromide(CTAB) < benzalkonium chloride (BZ). The permeability of PS-ODN through the rat skin increased in the presence of BZ. The fluxs of PS-ODN with BZ were increased by addition of Pluronic F 68 or Triton X-100 to phosphate buffered saline (PBS), respectively. When the mole ratio of PS-ODN to BZ is 1:10, the fluxs penetrated of PS-ODN with BZ was greatest. The increase of the permeability in the presence of BZ might be due to the formation of lipophilic ion-pair complex between PS-ODN and BZ. By regulation of mole ratio of PS-ODN to BZ, the development of topical dosage forms using PS-ODN as scar formation inhibitor will be possible with minimal systemic exposure.

• 한국식품영양과학회지
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• 제42권10호
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• pp.1656-1663
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• 2013

고등어 육을 이용한 소시지 제조에 있어서 그 최적 조건을 확립하기 위해 수세 횟수(0, 1, 2, 3회), 소금(1, 1.5, 2, 3%), 인산염(0, 0.1, 0.3, 0.5%), 설탕(0, 1, 2, 3%) 및 전분(0, 1, 3, 5%) 첨가량을 달리하여 소시지를 제조한 후 색도, texture, 겔 강도 및 관능평가를 실시하였다. 색도에 있어서 수세 횟수, 소금 및 전분 농도에 따라 유의적으로 백색도가 증가하였으나 인산염 및 설탕 농도에 따라서는 감소하는 경향을 나타냈다. Texture 측정에 있어서 경도 및 겔 강도의 경우, 수세 2회, 소금 2%, 설탕 2% 및 전분 5% 처리구에서 유의적으로 가장 높은 값을 나타냈으며 인산염 처리구는 농도에 따른 유의적인 차이는 없었다. 관능평가 결과, 수세 2회 처리구가 색, 향 및 전체적 호감도에서 가장 높은 점수를 받았으며 소금 2% 처리구는 모든 항목에서 가장 높은 점수를 받았다. 인산염 처리구의 경우, 맛, 탄성 및 전체적 호감도에 있어서 농도 의존적으로 높은 점수를 받았으며, 설탕 2%처리구는 탄성 및 전체적 호감도, 전분 5% 처리구는 전체적 호감도에서 가장 높은 점수를 받았다. 이상의 결과를 종합해 볼 때, 수세 2회, 소금 2%, 인산염 0.5%, 설탕 2% 및 전분 5% 첨가가 고등어 육을 이용한 소시지 제조 시 최적 배합조건인 것으로 사료된다.

• 상하수도학회지
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• 제26권5호
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• pp.713-721
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• 2012

강이나 호수로 유입되는 인(P)이 종종 부영양화의 가장 큰 제한요소로 작용한다. 그런데 하수처리장의 방류수가 자연수계에 인의 중요한 공급처로 작용하는 경우가 많기 때문에 하수처리장의 최종 처리수에서 인의 제거가 요구된다. 하수에서 인을 제거할 수 있는 많은 기술 중에서, 활성 칼슘-황토의 복합체를 이용한 흡착기술을 연구하였다. 칼슘을 황토에 첨가하여 인의 흡착 용량과 흡착강도를 증가시켰다. 칼슘을 첨가한 황토를 최적 온도로 밝혀진 $400^{\circ}C$의 고온에서 활성화시켰다. $400^{\circ}C$ 미만에서 활성화시킨 칼슘-황토는 하수처리 공정의 활성칼슘-황토 복합체를 이용한 처리조에 적용하기엔 강도가 부족하였다. 반면 $400^{\circ}C$ 초과 온도에서 활성화시킨 칼슘-황토 복합체는 복합체 표면이 유리화되어 흡착용량이 감소하였다. 활성칼슘-황토 복합체는 표면에 충분한 기공이 발달하지 못하여 인의 흡착용량에 한계는 있으나 칼슘을 첨가하였기 때문에 흡착강도는 높았다. 활성칼슘-황토는 입자형 복합체로 만들어졌다. 제조된 복합체를 흡착칼럼에 채워 하수처리공정에 적용하였다. 활성칼슘-황토의 복합체를 충진한 칼럼을 파일롯트 플랜트에 적용한 결과 0.5 mg/l의 인의 농도를 0.1 mg/l로 낮출 수 있었고, 이온성 인을 4개월의 운전기간 동안 완전하게 흡착시켜 제거할 수 있었다.

• 한국균학회지
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• 제10권2호
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• pp.57-65
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• 1982

경정곰팡이(Aspergillus niger)의 포자형성(胞子形成)을 액침배양법(液浸培養法)과 동조적방법(同調的方法)으로 여행(旅行)하면서 인산화합물(燐酸化合物), 고인산화(高燐酸化)뉴크레오티드, 및 RNA(핵산)(核酸)의 동태(動態)를 연구(硏究)하였다. 결과(結果)는 다음과 같이 요약(要約)된다. 1. 곰팡이의 포자형성시(胞子形成時)에 유기인산화합물(有機燐酸化合物)의 양(量)이 증가(增加)하였으며, 무기(無機) Polyphosphate의 양(量)은 반대(反對)로 감소(減少)하였다. 2. 무기인산양(無機燐酸量)은 변동(變動)하지 않았으며, 총인산화합물(總燐酸化合物)의 양(量)은 초기균사생장시(初期菌絲生長時)에는 감소(減少)하고 포자낭병시기(胞子囊柄時期)부터는 변동(變動)하지 않았다. 3. RNA핵산구획(核酸區劃)에 있어서 orcinol 반응양성구(反應陽性區)의 흡광도(吸光度)가 급격(急激)히 증가(增加)하였다. 그러나 UV흡광도(吸光度)는 완만하게 증가(增加)하였다. 4. 포자낭병(胞子囊柄)및 포자형성시기(胞子形成時期)에 guanosinetetraphosphate가 검출현(檢出現) 되었다. 5. 고분자양성(高分子量性) RNA (rRNA분획(分劃))의 polyacrylamide gel 전기영동(電氣泳動)을 2.6% gel로서 시행(施行)한 바 polyphosphate와 RNA의 결합물(結合物)이 상당양(相當量) 존재(存在)함을 알았다. 이상(以上)의 결과(結果)로 보아 검정곰팡이의 분화과정(分化過程)에 있어서 고인산화(高燐酸化) RNA 화합물(化合物)의 존재(存在)가 확인(確認)되었으며, 이 화합물(化合物) 가운데 guanosine tetraphosphate (G4P)의 존재(存在)가 진핵미생물(眞核微生物)인 곰팡이에서도 검출(檢出)되었음을 지적(指摘)한다.

• Bulletin of the Korean Chemical Society
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• 제32권6호
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• pp.2063-2069
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• 2011

We studied the interaction of 3,3',3'',3'''-ethylenetetrakis-4-hydroxycoumarin (EHC) with bovine serum albumin (BSA) in acetate buffer and phosphate buffer with different pH values by UV-vis absorption spectrometry and fluorescence spectrometry respectively. It was found that the pH values of the buffer solutions had an effect on the interaction process. In acetate buffer of pH 4.70, the carbonyl groups in EHC bound to the amino groups in BSA by means of hydrogen bond and van der Waals force, which made the extent of peptide chain in BSA changed. By contrast, in phosphate buffer of pH 7.40, hydrophobic force played a major role in the interaction between EHC and BSA, while the hydrogen bond and van der Waals force were also involved in the interaction. The results of spectrometry indicated that BSA could enhance the fluorescence intensity of EHC by forming a 1:1 EHC-BSA fluorescent complex through static mechanism at pH 4.70 and 7.40 respectively. Furthermore, EHC bound on site 1 in BSA.