• 제목/요약/키워드: Concentration Gradient

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Simultaneous Determination of Paeoniflorin and Glycyrrhizin in Sayuk-san by HPLC/DAD

  • Lee, Mi-Kyeong;Lee, Ki-Yong;Kim, Seung-Hyun;Jeon, Min-Ji;Cho, Jung-Hee;Oh, Mi-Hyun;Baek, Ju-Hyun;Kim, Hyo-Jin;Sung, Sang-Hyun
    • Journal of Pharmaceutical Investigation
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    • v.39 no.1
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    • pp.23-27
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    • 2009
  • A high performance liquid chromatographic (HPLC) method for the simultaneous determination of marker constituents, paeoniflorin and glycyrrhizin was established for the quality control of traditional herbal medicinal preparation, Sayuk-san (SYS). Separation and quantification were successfully achieved with a Waters XTerra RP18 column ($5{\mu}m$, $4.6mm\;I.D.{\times}150mm$) by gradient elution of a mixture of acetonitrile and water containing 0.03% phosphoric acid (pH 2.03) at a flow rate of 1.0 mL/min. The diode-array UV/vis detector (DAD) was used for the detection and the wavelength for quantification was set at 230 nm. The presence of paeoniflorin and glycyrrhizin in this decoction was ascertained by retention time, spiking with each authentic standard and UV spectrum. All two compounds showed good linearity ($r^2$>0.996) in a relatively wide concentration ranges. The R.S.D. for intra-day and inter-day precision was less than 7.3% and the limits of detection (LOD) were less than 55.7 ng. The mean recovery of each compound was $102.3{\sim}111.1%$ with R.S.D. values less than 4.6%. This method was successfully applied to the determination of contents of paeoniflorin and glycyrrhizin in three commercial products of SYS. These results suggest that the developed HPLC method is simple, effective and could be readily utilized as a quality control method for commercial SYS products.

An Experimental Study on the Control of the Combustion Rate by Temperature Control of Gas Entrained into the Filter in Burner-Type Particulate Trap (버너방식 DPF 시스템에서 가스온도 제어를 통한 입자상물질 연소율제어의 실험적 검증)

  • Park, D. S.;Kim, J. U.;Cho, H.;Kim, E. S.
    • Transactions of the Korean Society of Automotive Engineers
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    • v.5 no.4
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    • pp.130-141
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    • 1997
  • Work on the reduction of particulate matter(PM) from a diesel vehicl has led to a new trp system and a control method to control the combustion rate of the PM filtrated in the trap, which was named as 'Active Exhaust Feeding Regeneration(AEFR) System' by its operation mechanism. Ceramic cordierite filter is a major component of the trap and susceptible to thermal shock. Therefore the system should be designed to reduce the peak temperature and temperature gradients in the trap ; these have been considered to be the main factors causing thermal shock of the filter during the regeneration. It uses the engine's exhaust gas partially for the regeneration of the ceramic filter. It controlled bypass flow rate of the engine's exhaust gas precisely to control the temperature of the gas entrained into the filter. Gas temperatures were measured inside filter, and the oxygen concentration at the outlet of the filter was also monitored during the regeneration to analyze the combustion process of the PM. The temperature distributions and temperature gradients in the filter during the regeneration varied widely according to the regeneration control schemes. Finally, this system shows relatively low peak temperature and temperature gradients in the filter during its regeneration. It is considered that this system uses a mew method to control the combustion rate of the PM, which is different from the methods used in the previous studies.

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Anti-inflammatory Effect of Jatrorrhizine from Phellodendron amurense in Lipopolysaccharide-stimulated Raw264.7 Cells (Lipopolysaccharide로 유도된 Raw264.7 cell에서 Phellodendron amurense의 Jatrorrhizine에 의한 염증 억제효과)

  • Cho, Young-Je
    • Journal of Applied Biological Chemistry
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    • v.54 no.2
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    • pp.114-119
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    • 2011
  • n-Butanol extracts from Phellodendron amurense have about 50% inhibitory activity against hyaluronidase. The anti-inflammatory compound was isolated from P. amurense by Sephadex LH-20 and MCI-gel CHP-20 column chromatography with gradient elution. As a the result, its structure was identified as Jatrorrhizine by the interpretation of spectroscopic analyses including $^1H$- and $^{13}C$-NMR. In anti-inflammatory activity, the expression of nitric oxide (NO) was inhibited as above 60% at 100 ${\mu}g/mL$ concentration of extracts and then purified Jatrorrhizine from P. amurense. The inhibitory activities against the expression of inducible NO syntase (iNOS) and cyclooxygenase-2 (COX-2) were 45% and 29%. It seems that the extracts and purified Jatrorrhizine from P. amurense were expected anti-inflammatory effect in lipopolysaccharide (LPS)-stimulated Raw264.7 cells.

Spatiotemporal Variations and Possible Sources of Ambient PM10 from 2003 to 2012 in Luzhou, China

  • Ren, Dong;Li, Youping;Zhou, Hong;Yang, Xiaoxia;Li, Xiaoman;Pan, Xuejun;Huang, Bin
    • Environmental Engineering Research
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    • v.19 no.4
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    • pp.331-338
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    • 2014
  • Descriptive statistics methods were used to study the spatiotemporal variations and sources of ambient particulate matter ($PM_{10}$) in Luzhou, China. The analyzed datasets were collected from four national air quality monitoring stations: Jiushi (S1), Xiaoshi (S2), Zhongshan (S3), Lantian (S4) over the period of 2003-2012. This city was subjected serious $PM_{10}$ pollution, and the long-term annual average $PM_{10}$ concentrations varied from 76 to $136{\mu}g/m^3$. The maximum concentration was more than 3-fold of the annual average ($40{\mu}g/m^3$) issued by EPA-China for the ambient air quality. General temporal pattern was characterized by high concentrations in winter and low concentrations in summer, and general spatial gradient was in the reduction order of S2 > S4 > S3 > S1, which were both due to different particulate contributors and special meteorological conditions. The source apportionment indicated that vehicular emissions, road dusts, coal burning and chemical dusts were the major contributors of the identified $PM_{10}$ pollution, and the vehicular emissions and the road wear re-suspended particles dominated the heavy $PM_{10}$ pollution in recent years. Two other potential sources, agricultural and celebration activities could decrease the air quality in a short term. Finally, some corresponding suggestions and measures were provided to improve the air quality.

Analysis and Quantification of Ammonia-Oxidizing Bacteria Community with amoA Gene in Sewage Treatment Plants

  • Hong, Sun Hwa;Jeong, Hyun Duck;Jung, Bongjin;Lee, Eun Young
    • Journal of Microbiology and Biotechnology
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    • v.22 no.9
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    • pp.1193-1201
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    • 2012
  • The analysis and quantification of ammonia-oxidizing bacteria (AOB) is crucial, as they initiate the biological removal of ammonia-nitrogen from sewage. Previous methods for analyzing the microbial community structure, which involve the plating of samples or culture media over agar plates, have been inadequate because many microorganisms found in a sewage plant are unculturable. In this study, to exclusively detect AOB, the analysis was carried out via denaturing gradient gel electrophoresis using a primer specific to the amoA gene, which is one of the functional genes known as ammonia monooxygenase. An AOB consortium (S1 sample) that could oxidize an unprecedented 100% of ammonia in 24 h was obtained from sewage sludge. In addition, real-time PCR was used to quantify the AOB. Results of the microbial community analysis in terms of carbon utilization ability of samples showed that the aeration tank water sample (S2), influent water sample (S3), and effluent water sample (S4) used all the 31 substrates considered, whereas the AOB consortium (S1) used only Tween 80, D-galacturonic acid, itaconic acid, D-malic acid, and $_L$-serine after 192 h. The largest concentration of AOB was detected in S1 ($7.6{\times}10^6copies/{\mu}l$), followed by S2 ($3.2{\times}10^6copies/{\mu}l$), S4 ($2.8{\times}10^6copies/{\mu}l$), and S3 ($2.4{\times}10^6copies/{\mu}l$).

CaCO3 Biomineralization in Microfluidic Crystallizer (미세유체 결정화기를 이용한 탄산칼슘 Biomineralization)

  • Seo, Seung Woo;Ko, Kwan Young;Lee, Chang Soo;Kim, In Ho
    • Korean Chemical Engineering Research
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    • v.51 no.1
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    • pp.151-156
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    • 2013
  • Crystallization of $CaCO_3$ is practiced on a polymethylsiloxane (PDMS) - based microfluidic system. Liquid- liquid reaction was investigated by mixing calcium chloride ($CaCl_2$) and sodium carbonate ($Na_2CO_3$) solution to crystallize $CaCO_3$. Aspartic acid (Asp) was added to investigate the morphology change such as vaterite and calcite. Suitable ratio of $Na_2CO_3$ and $CaCl_2$ was searched for initial seed formation. Christmas tree model was used as microfluidic device to form concentration gradient of $Na_2CO_3$ and $CaCl_2$. After observing microfluidic channel by using optical microscope, we found that seeds of $CaCO_3$ were formed under the condition that the ratio of $Na_2CO_3$ and $CaCl_2$ was 2:1. Morphology of crystals were also observed as $CaCO_3$ crystals grow. When Asp was added, vaterite crystal was more frequently found in two morphologies (vaterite and calcite) and seed formation and crystal growth were inhibited.

Analysis of intracellular amino acids in the fermentation of Pichia pastoris X-33 and KM71H

  • Han, Kyung-Ah;Kim, Sun-Yong;Rhee, Jong-Il
    • 한국생물공학회:학술대회논문집
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    • 2005.10a
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    • pp.651-654
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    • 2005
  • Analysis of extra- and intra- cellular metabolites is very important to study cell metabolish. Intracellular amino acids in yeast are of great interest as precursors of desired products in biomass production of the feed industries and the production of glutamate. In this study, the fermentations of P. pastoris X-33 and KM71H were carried out in shake flasks. After centrifugation, the harvested cells were mechanically disrupted by using glass bead. The supernatants were used to analyze intracellular amino acid by HPLC system. For HPLC analysis, Resolve C18 column was used with Fluorescence detector. The OPA(o-phthalaldehyde) derivation reaction was employed for analysing amino acids at 30 $^{\circ}C$, 1 ml/min and gradient mode. The concentration of intracellular protein was measured by spectrophotometer.

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Simultaneous Analysis of Six Compounds in Yijin-tang by HPLC-PDA (HPLC-PDA을 이용한 이진탕 중 6종 성분의 동시분석)

  • Kim, Seong-Sil;Kim, Jung-Hoon;Shin, Hyeun-Kyoo;Seo, Chang-Seob
    • Herbal Formula Science
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    • v.21 no.1
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    • pp.71-79
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    • 2013
  • Objectives : Yijin-tang has been used in the treatment of gastrointestinal diseases such as irritable bowel syndrome, gastritis, and gastric ulcer. In this study, a high-performance liquid chromatography (HPLC) method was established for simultaneous analysis of six compounds, liquiritin, glycyrrhizin, hesperidin, 6-gingerol, homogentisic acid, and 3,4-dihydroxybenzaldehyde in Yijin-tang, a traditional Korean herbal medicinal preparation. Methods : A Gemini C18 column was used for the separation of six constituents at $40^{\circ}C$. The mobile phase using gradient elution consist of two solvent systems, 1.0% acetic acid in water (A) and 1.0% acetic acid in acetonitrile (B). The flow-rate was 1.0 mL/min and injection volume was $10{\mu}g$. The detector was a photodiode array (PDA) detector set at 254 nm and 280 nm. Results : The calibration curves of six compounds showed good linearity in various concentration ranges ($R^2{\geq}0.9997$). The limits of detection (LOD) and limits of quantification (LOQ) were 0.028-$0.192{\mu}g/mL$ and 0.093-$0.540{\mu}g/mL$, respectively. The RSD (%) of the intra and inter day validations were 0.03-0.84% and 0.05 -1.00%, respectively. Recovery was 96.14-01.90% and RSD (%) was less than 1.5%. Conclusions : The established simultaneous analysis methods will help management to improve the quality of Yijin-tang.

Quantification Analysis and Antioxidant Activity of Leejung-tang (LC-MS/MS를 이용한 이중탕(理中湯)의 정량분석 및 항산화 활성)

  • Seo, Chang-Seob;Kim, Ohn Soon;Kim, Yeji;Shin, Hyeun-Kyoo
    • Herbal Formula Science
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    • v.21 no.1
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    • pp.177-185
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    • 2013
  • Objectives : Leejung-tang (Lizhong-tang) has been used for treatment of gastrointestinal disorders in Korea. In this study, we performed quantification analysis of five marker components, liquiritin, ginsenoside Rb1, ginsenoside Rg1, glycyrrhizin, and 6-gingerol in Leejung-tang using a ultra performance liquid chromatography- electrospray ionization-mass spectrometer (UPLC-ESI-MS). In addition, we evaluated antioxidant activity of Leejung- tang. Methods : The column for separation of five constituents used a UPLC BEH C18 ($100{\times}2.1mm$, $1.7{\mu}m$) maintained at $45^{\circ}C$. The mobile phase consisted of two solvent systems, 0.1% (v/v) formic acid in H2O (A) and CH3CN (B) by gradient flow. The flow rate was 0.3 mL/min with detection at mass spectrometer. The antioxidative activities conduct an experiment on 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) and 2,2-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activities of Leejung-tang. Results : Calibration curves of five marker compounds were acquired with r2 values > 0.99. The amount of the five compounds in Leejung-tang were 0.07 - 0.84 mg/g. The concentration required for 50% reduction (RC50) against ABTS radical was 119.02 ug/mL. In addition, the scavenging against DPPH radical of Leejung-tang was 11.4%, 14.5%, 19.8%, 29.6%, and 49.2% at 25 ug/mL, $50{\mu}g/mL$, $100{\mu}g/mL$, $200{\mu}g/mL$, and $400{\mu}g/mL$, respectively. Conclusions : The established LC-MS/MS method will be helpful to improve quality control of Leejung-tang. In addition, Leejung-tang is a potential antioxidant therapeutic agent.

Imperatorin is Transported through Blood-Brain Barrier by Carrier-Mediated Transporters

  • Tun, Temdara;Kang, Young-Sook
    • Biomolecules & Therapeutics
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    • v.25 no.4
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    • pp.441-451
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    • 2017
  • Imperatorin, a major bioactive furanocoumarin with multifunctions, can be used for treating neurodegenerative diseases. In this study, we investigated the characteristics of imperatorin transport in the brain. Experiments of the present study were designed to study imperatorin transport across the blood-brain barrier both in vivo and in vitro. In vivo study was performed in rats using single intravenous injection and in situ carotid artery perfusion technique. Conditionally immortalized rat brain capillary endothelial cells were as an in vitro model of blood-brain barrier to examine the transport mechanism of imperatorin. Brain distribution volume of imperatorin was about 6 fold greater than that of sucrose, suggesting that the transport of imperatorin was through the blood-brain barrier in physiological state. Both in vivo and in vitro imperatorin transport studies demonstrated that imperatorin could be transported in a concentration-dependent manner with high affinity. Imperatorin uptake was dependent on proton gradient in an opposite direction. It was significantly reduced by pretreatment with sodium azide. However, its uptake was not inhibited by replacing extracellular sodium with potassium or N-methylglucamine. The uptake of imperatorin was inhibited by various cationic compounds, but not inhibited by TEA, choline and organic anion substances. Transfection of plasma membrane monoamine transporter, organic cation transporter 2 and organic cation/carnitine transporter 2/1 siRNA failed to alter imperatorin transport in brain capillary endothelial cells. Especially, tramadol, clonidine and pyrilamine inhibited the uptake of [$^3H$]imperatorin competitively. Therefore, imperatorin is actively transported from blood to brain across the blood-brain barrier by passive and carrier-mediated transporter.