• Toxicological Research
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• 제25권4호
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• pp.243-251
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• 2009

Present study was conducted to evaluate the anti oxidative activity of the Agrimonia pilosa-Ledeb leaves on non-lipid oxidative damage. The antioxidative activity of methanolic (MeOH) extract of the Agrimonia pilosa-Ledeb leaves on non-lipid oxidation, including liposome oxidation, deoxyribose oxidation, protein oxidation, chelating activity against metal ions, scavenging activity against hydrogen peroxide, scavenging activity against hydroxyl radical and 2'-deoxyguanosine (2'-dG) oxidation were investigated. The MeOH extract of the Agrimonia pilosa-Ledeb leaves exhibited high anti oxidative activity in the liposome model system. Deoxyribose peroxidation was inhibited by the MeOH extract of the Agrimonia pilosa-Ledeb leaves and MeOH extract of the Agrimonia pilosa-Ledeb leaves provided remarkable protection against damage to deoxyribose. Protective effect of MeOH extracts of the Agrimonia pilosa-Ledeb leaves on protein damage was observed at $600{\mu}g$ level (82.05%). The MeOH extracts of the Agrimonia pilosa-Ledeb leaves at $300{\mu}g$ revealed metal binding ability (32.64%) for hydrogen peroxide. Furthermore, the oxidation of 2'-deoxyguanosine (2'-dG) to 8-hydroxy-2-deoxyguanosine (8-OH-2'dG) was inhibited by MeOH extracts of the Agrimonia pilosa-Ledeb leaves and scavenging activity for hydroxyl radical exhibited a remarkable effect. From the results in the present study on biological model systems, we concluded that MeOH extract of the Agrimonia pilosa-Ledeb leaves was effective in the protection of non-lipids against various oxidative model systems.

• Journal of Microbiology and Biotechnology
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• 제10권5호
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• pp.612-619
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• 2000

To investigate the biochemical properties of V. mimicus metalloprotease, whose gene was isolated previously from Vibrio mimicus ATCC33653, overexpression and purification were attempted. The 1.9 kb of open reading frame was amplified by PCR from pVMC193 plasmid which ligated the VMC gene with pUC19 and introduced into Escherichia coli BL21 (DE3) using the overexpression vector, pET22b (+). The overexpressed metalloprotease (VMC) was purified with Ni-NTA column chromatography and characterized with various protease inhibitors, pHs, temperatures, and substrates. The purified VMC showed the proteolytic activity against gelatin, soluble and insoluble collagens, and synthetic peptides. Unlike the observations made with all metalloproteases originated from other Vibrio sp., the VMC did not hydrolyze the casein. The proteolytic activity was critically decreased when the VMC was treated with metal chelating reagents, such as EDTA, 2,2-bipyridine, and 1, 10-phenanthroline. In particular, the 71 kDa VMC exhibited the hemagglutinating activity against human erythrocyte. As the purified VMC was treated with $CuCl_2$ and $NiCl_2$ for the chemical modification of metal binding, the proteolytic activity and hemagglutinating activity were profoundly influenced. The multialignment analysis made on the reported Vibrio metalloproteases showed the difference of amino acid sequence similarity between the two distinctive classes of Vibrio metalloproteases.

• Preventive Nutrition and Food Science
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• 제20권1호
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• pp.29-37
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• 2015

Most of the wheat germ in cereal grains is removed during the milling process. Various physiological effects have been reported for bioactive substances in wheat germ such as phenolic acids and flavonoids. In this study, the antioxidant and anti-adipogenic effects of ethanol extracts from wheat germ (WGE) and wheat germ fermented with Aspergillus oryzae (F-WGE) were investigated in HepG2 and 3T3-L1 cells. The anti-oxidant activity of F-WGE was demonstrated by a dose-dependent increase in the enhanced scavenging capacity of hydroxyl radicals and $Cu^{2+}$-chelating activity compared to WGE. WGE and F-WGE treatment at doses between 10 and $400{\mu}g/mL$ did not affect the viability of HepG2 and 3T3-L1 cells. Intracellular ROS levels from $Cu^{2+}$-induced oxidative stress were significantly decreased by F-WGE treatment in HepG2 cells compared to WGE. Lipid accumulation was increased in 3T3-L1 adipocytes by $100{\mu}M$ $Fe^{2+}$ treatment, but the accumulation was strongly inhibited by $100{\mu}g/mL$ of WGE and F-WGE treatment. These results suggest that changes in bioactive substances during the fermentation of wheat germ can potentiate scavenging activities against transition metal-induced oxidative stress and lipid accumulation in 3T3-L1 adipocytes. Therefore, we propose that F-WGE is a novel food materials and provided scientific evidences for its efficacy in the development of functional foods.

• Bulletin of the Korean Chemical Society
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• 제32권2호
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• pp.444-450
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• 2011

A novel method that utilizes poly(5-methyl-2-thiozyl methacrylamide-co-2-acrylamido-2-methyl-1-propanesulfonic acid-co-divinylbenzene) [MTMAAm/AMPS/DVB] as a solid-phase extractant was developed for simultaneous preconcentration of trace Cd(II), Co(II), Cr(III), Cu(II), Fe(III), Mn(II), Ni(II), Pb(II), and Zn(II) prior to the measurement by flame atomic absorpiton spectrometry (FAAS). Experimental conditions for effective adsorption of the metal ions were optimized using column procedures. The optimum pH value for the simultaneously separation of the metal ions on the new adsorbent was 2.5. Effects of concentration and volume of elution solution, sample flow rate, sample volume and interfering ions on the recovery of the analytes were investigated. A high preconcentration factor, 100, and low relative standard deviation values, $\leq$1.5% (n = 10), were obtained. The detection limits (${\mu}gL^{-1}$) based on the 3s criterion were 0.18 for Cd(II), 0.11 for Co(II), 0.07 for Cr(III), 0.12 for Cu(II), 0.18 for Fe(III), 0.67 for Mn(II), 0.13 for Ni(II), 0.06 for Pb(II), and 0.09 for Zn(II). The validation of the procedure was performed by the analysis of two certified reference materials. The presented method was applied to the determination of the analytes in various environmental samples with satisfactory results.

• 펄프종이기술
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• 제40권3호
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• pp.36-41
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• 2008

It is known that ethanolamines play a critical role for deacidification of paper sized by alum-rosin. However, amines also are effective as a chelating agent of metal. The present work was focused on whether amines could scavenge metals and prevent from the aging of paper. Metals such as alum, copper(II) and iron(III) was added to paper, and the paper treated with amines was aged in a thermo-hygrostat for 3-6 days. In the case of paper added to alum, the amines efficiency against paper aging was good in the oder of triethanolamine, diethanolamine and monoethanolamine attributable to the intensity of basicity and steric effect. Even in the case of paper treated with copper(II) chloride, iron(III) chloride, and copper(II) chloride, the significant preservation efficiency was shown by ethanolamine during accelerated aging. This outcome pinpoints the fact that ethanolamine can prevent paper aging not only from acid by neutralizing acid contained in paper but also from metals by producing of complexes with metals. These consequences above convince that ethanolamine makes it possible for mass deacidification for paper which contains acid and metals. Future studies should be conducted concerning whether, in reality, the treatment of its gas mode, in a single or multiple applications, has significant effect on lessening paper aging.

• 한국식품영양과학회지
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• 제32권8호
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• pp.1318-1322
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• 2003

천연에서 생산되는 식물성 천연항산화성 물질인 flavonoid의 지질 산화 억제능과 라디칼 봉쇄능 및 금속착체 형성능을 비롯하여 ACE 저해능을 조사하고 그 결과를 보고하였다. 즉, flavonoid와 linoleic acid를 반응시킨 결과 linoleic acid의 산화를 크게 억제하는 것으로 나타났으며 특히, 산화의 초기에 억제 효과가 큰 것으로 나타났다. 이들의 DPPH에 대한 수소 공여능을 조사한 실험에서 공시한 대부분의 flavonoid가 양질의 효과를 나타내었으나 naringin과 kaempferol은 봉쇄능이 약한 것으로 나타났으나 daidzein과 morin, quercetin 등은 아주 우수한 radical 봉쇄능을 가지는 것으로 나타났다. 한편, rutin의 금속 착체 형성능을 조사한 실험에서는 C $u^{2+}$과 $Mg^{2+}$에 대한 결합능이 있는 것을 확인할 수 있었다. 그리고 ACE 저해능을 조사한 실험에서는 모든 시료에서 ACE 활성을 저해하는 결과를 나타내었다. 특히, isoflavone인 daidzein과 genistein에서 저해능이 가장 큰 것으로 나타났다.

• 한국염색가공학회:학술대회논문집
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• 한국염색가공학회 2005년도 춘계학술발표회 논문집
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• pp.213-215
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• 2005

The metal complexes can be influenced not only by the central metal atoms and the substituent groups, but also by the native of the chelating atoms. For example, near-infrared absorbing chromophores were synthesized by the reaction of phenylenediamine derivatives with a solution of pottassium hydroxide followed by the addition of nickel(II) chloride. These dyes provide absorbing infrared light over 780-840 nm with an extinction coefficient of $2.5-6.0{\times}10^4$. By introduction of alkyl, alkoxyl, cyano, and other functional group into the parent dye, these dyes greatly improved the solubility in organic solvent. New near-infrared absorbing donor-acceptor chromophores have been investigated by varying the electron donating and accepting strength of the two halves of the molecule. The cyanine chromophores permit the simplest way of obtaining systems that absorb well into the near-infrared region of the spectrum. Cyanine dyes possess high extinction coefficients that initially increase with Increasing chain length. These chromophores could be useful in near-infrared optical materials.

• 한국지하수토양환경학회지:지하수토양환경
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• 제18권1호
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• pp.6-15
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• 2013

The influence of processing fluids and electrode spacing on the electrokinetic process was evaluated to remediate As-, Cu-, Pb-contaminated soil. Single and mixture of sodium citrate, EDTA and NaOH was used to investigate the metal extraction. EDTA for washing reagent showed the highest removal efficiency. Based on the extraction result, the electrode spacing (20, 40, 60 cm) on the electrokinetic process was investigated to remove the multi-metals from soil. The highest removal was observed at the experiment with 60 cm of electrode spacing, however, the correlation between electrode spacing and removal of metals was not clear. The electrode spacing influenced the amount of accumulated electro-osmotic flow. BCR sequential extraction showed that electrokinetic process removed the fractionation of metals bound to Fe-Mn oxyhydroxide.

• 대한화학회지
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• 제43권1호
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• pp.36-41
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• 1999

Mercaptoacetic acid를 이용하여 흡착벗김 전압전류법으로 미량의 게르마늄을 정량하는 방법을 연구하였다. 이때 지지전해질은 0.25 M NaCl 용액(pH 6.0)을 사용하였고, mercaptoacetic acid의 농도는 $5.0{\times}10^{-6}M$이 되도록 조절하여 실험하였다. Ge(IV)-Mercaptoacetic acid 착물의 봉우리 전위는 -1.402V vs. Ag/AgCl에서 나타났다. 착물의 봉우리 전위에 미치는 NaCl의 농도, mercaptoacetic acid의 농도, 축적 시간등에 대하여 조사하였다. 또한, Amberlite IRC-718 킬레이트 수지를 다른 이온들로 부터 Ge(IV)을 분리하는데 적용하였다.

• BMB Reports
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• 제43권4호
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• pp.284-290
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• 2010

Replication of positive-strand RNA virus is mediated by a virus-encoded RNA-dependent RNA polymerase (RdRp). To study the replication of Ectropis obliqua virus (EoV), a newly identified insect virus belonging to the family Iflaviradae, we expressed the RNA polymerase domain in Escherichia coli and purified it on a Ni-chelating HisTrap affinity column. It is demonstrated that EoV RdRp initiated RNA synthesis in a primer and poly (A)-dependent manner in vitro. Furthermore, the effect of primer concentration, temperature, metal ions ($Mg^{2+}$, $Mn^{2+}$, and $K^+$) on enzymatic activity were determined. Our study represented a first step towards understanding the mechanism of EoV replication.