• Title/Summary/Keyword: Dilution Factor

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Protein Aggregation and Adsorption upon In vitro Refolding of Recombinant Pseudomonas Lipase

  • Lee, Young-Phil;Rhee, Joon-Shick
    • Journal of Microbiology and Biotechnology
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    • v.6 no.6
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    • pp.456-460
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    • 1996
  • Recombinant Pseudomonas lipase was used to study protein aggregation and adsorption upon in vitro refolding. Protein adsorption as well as aggregation was responsible for major side reactions upon in vitro refolding as a function of protein concentration. The optimal range of protein concentration was determined by the relative contribution of protein aggregation and adsorption. Above the optimal range, the yield of active lipase inversely correlated with protein aggregation, showing a competition between folding and aggregation. However, adsorption of protein rather than protein aggregation is thought to contribute as a major side reaction of the refolding process at sub-optimal concentrations at which the formation of aggregates should be more reduced. Protein aggregation was influenced by the amount of guanidine hydrochloride in the refolding solvent. The refolding temperature was a critical factor determining the extent of protein aggregation. The refolding yield was also affected by the dilution fold and dilution mode, which suggests that the refolding process might kinetically compete with the rate of mixing.

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Evaluation of Metal Oxide Semiconductor and Electrochemical Gas Sensor Array Characterization for Measuring Wastewater Odor (폐수의 악취측정을 위한 금속산화물 반도체 및 전기화학식 가스센서 어레이 특성 평가)

  • Yim, Bongbeen;Lee, Seok-Jun;Kim, Sun-Tae
    • Journal of Sensor Science and Technology
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    • v.24 no.1
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    • pp.29-34
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    • 2015
  • This study aimed to evaluate the characterization of a metal oxide semiconductor and electrochemical gas sensor array for measuring wastewater odor. The sensitivity of all gas sensors observed in sampling method by stripping was 6.7 to 20.6 times higher than that by no stripping, except sensor D (electrochemical gas sensor). The average reduction ratio of sensor signal as a function of initial dilution rate of wastewater was in the order of food plant > food waste reutilization facility > plating plant. The sensitivity of gas sensors was dependent on both the type of wastewater and the dilution rate. The sensor signals observed by the gas sensor array were correlated with the dilution factor (OU) calculated by the air dilution sensory test with several wastewater ($r^2=0.920{\sim}0.997$), except the sensor signals of sensor D measured in the plating plant wastewater. It seems likely that the gas sensor array plays a role in the evaluation of odor in wastewater and is useful tool for on-site odor monitoring in the wastewater facilities.

Study of Nano-emulsion Formation by Different Dilution Method (희석 방법에 따른 나노에멀젼 형성 연구)

  • Cho, Wan-Goo;Han, Sang-Gil
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.38 no.3
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    • pp.201-207
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    • 2012
  • The influence of different dilution procedures on the properties of oil-in-water (O/W) nano-emulsions obtained by dilution of oil-in-ethanol (O/E) microemulsions with water has been studied. The system water/ethanol/nonionic surfactant/silicone oil with ethanol was chosen as model system. The dilution procedures consisted of adding water (or microemulsion) stepwise. By mixing O/E microemulsions into water, nano-emulsions with droplet diameters of 30 nm were obtained. In contrast, by mixing water into O/E microemulsion, emulsions with diameter of 400 nm were obtained The dilution methods were shown to be a key factor determining the properties of the emulsions. There were no change in diameters of nanoemulsion droplets against time, however sizes of droplets in the emulsion with larger droplets were increased with time and the mechanism of unstability was thought to be Ostwald ripening.

The Immune-Enhancing Effect of Mountain Gown ginseng, Mountain Cultivated ginseng, and Panax ginseng (산삼(山蔘), 장뇌삼(長腦蔘), 인삼(人蔘)의 면역증강(免疫增强)효과 비교연구)

  • Chung, Dae-Kyoo;Kwon, Soon-Joo
    • Journal of Oriental Neuropsychiatry
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    • v.15 no.2
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    • pp.89-101
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    • 2004
  • Objective : The present experiments were designed to study on the immune-enhancing effect of Mountain grown ginseng, Mountain cultivated ginseng, and Panax ginseng Method : In order to compare the immune-enhancing effect of moutain grown ginseng, moutain cultivated ginseng and Panax ginseng, the study was done through the forced swimming test (FST), measurement of T helper Th1, Th2 cytokines and fatigue related factors. Result : Moutain grown ginseng and panax ginseng decreased the immobility time in the FST compared to the control. Glucose, blood urea nitrogen (BUN), creatinine, lactate dehydrogenase (LDH) and Total-protein (T-protein) in serum were investigated. The serum achieved from ginseng administered mouse showed higher BUN, T-protein than the control. moutain grown ginseng administered group showed lower LDH than the control group. moutain grown ginseng administered mouse showed higher glucose than the control. Creatinine was same in either experimental or control group. Ginseng-induced cytokine production in human T-cell line, MOLT-4 cells and mouse peritoneal macrophages were compared. Moutain cultivated ginseng (10-4 dilution) and panax ginseng (10-3 dilution) were increased the interferon $IFN-{\gamma}$ production compared with media control (about 1.6-fold P<0.05) at 48 h. Moutain grown ginseng (10-4 dilution) was increased the $IFN-{\gamma}$ and interleukin IL-4 production compared with media control (about l.4-fold for $IFN-{\gamma}$ and 1.6-fold for IL-4 P<0.05) at 48 h. Moutain grown ginseng (10-3 dilution) and moutain cultivated ginseng (10-4 dilution) were increased the turmor necrosis factor $TNF-{\alpha}$ production compared with $rIFN-{\gamma}$ treated cells (about 1.9-fold for $TNF-{\alpha}$ P<0.05), respectively. Moutain cultivated ginseng (10-3 dilution) was increased the IL-12 production compared with $rIFN-{\gamma}$ treated cell (about 1.7-fold for IL-12 P<0.05). Conclusion : These data suggest that three different three kinds of ginseng act on immune responses in different aspects.

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Mass Production of Mammalian Cells under Chemostat Cultivation (동물세포의 연속 대량생산에 관한 연구)

  • 이현용;강재구;박형환
    • Microbiology and Biotechnology Letters
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    • v.17 no.3
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    • pp.173-177
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    • 1989
  • Cell density was gradually decreased as the dilution rate was increased under chemostat cultivation of HeLa cells. Maxium cell density was maintained at the dilution rate of 0.020 (1/h) which was far less than the wash-out rate of 0.050 (1/h), Maxium cell productivity of 2 (mL of cells/L/h)was obtained at the dilution rate of 0.030 (1/h) by showing the culture also required maintenance period at low dilution rates, whose result meant the deviation of continuous culture theroy. Methods of indirectly measuring cell density have been introduced to represent mammalian cell growth, which are packed cell volume and oxygen uptake rate, and these values showed good linear relationship with actual cell density by having correlation factor of 0.90. Theoretical maximum oxygen yield, $Y_{O2}^{max}$ and maintenance oxygen consumption rate, m$_{O2}$, were estimated as 4.1$\times$10$^5$ (cells/mmole $O_2$) and 10.71$\times$10$^{-9}$ (mmole $O_2$/cells/h) by employing oxygen yield model.

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A Case Study of Prediction and Analysis of Unplanned Dilution in an Underground Stoping Mine using Artificial Neural Network (인공신경망을 이용한 지하채광 확정선외 혼입 예측과 분석 사례연구)

  • Jang, Hyongdoo;Yang, Hyung-Sik
    • Tunnel and Underground Space
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    • v.24 no.4
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    • pp.282-288
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    • 2014
  • Stoping method has been acknowledged as one of the typical metalliferous underground mining methods. Notwithstanding with the popularity of the method, the majority of stoping mines are suffering from excessive unplanned dilution which often becomes as the main cause of mine closure. Thus a reliable unplanned dilution management system is imperatively needed. In this study, reliable unplanned dilution prediction system is introduced by adopting artificial neural network (ANN) based on data investigated from one underground stoping mine in Western Australia. In addition, contributions of input parameters were analysed by connection weight algorithm (CWA). To validate the reliability of the proposed ANN, correlation coefficient (R) was calculated in the training and test stage which shown relatively high correlation of 0.9641 in training and 0.7933 in test stage. As results of CWA application, BHL (Length of blast hole) and SFJ (Safety factor of Joint orientation) show comparatively high contribution of 18.78% and 19.77% which imply that these are somewhat critical influential parameter of unplanned dilution.

Characteristics of the Bioreactors of Hydrogen-producing Immobilized Cells (II) -Overall Effectiveness Factor in Continuous Reactors- (수소생산 고정화 생물 반응기의 특성(II) -연속 반응기에서의 총괄 효율인자 -)

  • 이명재;선용호;한정우;조영일
    • Microbiology and Biotechnology Letters
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    • v.16 no.6
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    • pp.510-516
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    • 1988
  • The effects of input substrate concentration and dilution rate on mass transfer resistance in the operation of immobilized cell reactors were investigated using Rhodospirillum rubrum KS-301 immobilized by Ca alginate as reactor element and glucose as growth-limiting substrate. The kinetic parameters were obtained to estimate effectiveness factors. In the packed-bed reactor, internal mass transfer resistance was predominating although external resistance could not be neglected. The overall effectiveness factor was decreased with increase of dilution rate. In the continuous stirred-tank reactor, external resistance was nearly neglected and the overall effectiveness factor was not affected by dilution rate. In this experiment the overall effectiveness factors in PBR and CSTR were estimated to be 0.70 and 0.71 at D$_{i}$ = 0.2/h, R = 0.15 cm, and S$_{i}$ : 1.0g/L, respectively.

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Development of Bioreactors for Hydrogen-Producing Immobilized Photosynthetic Bacteria(II) : Evaluation of Immobilized Bioreactor for Hydrogen Productivity and Mass Transfer Resistance (광합성 박테리아를 이용한 고성능 수소 생산 고정화 생물반응기의 개발(II) :고정층 반응기와 연속 교반탱크 반응기에서의 수소 생산성 및 물질전달 저항 비교)

  • 선용호;한정우
    • KSBB Journal
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    • v.8 no.3
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    • pp.256-265
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    • 1993
  • In this study, it was observed that hydrogen productivity varied with changes of input g1ucose concentration and dilution rate in FBR( Fixed Bed Reactor), and CSTR(Continuous Stirred Tank Reactor). We evaluated and compared reaction rate Parameters and internal external and overall mass transfer resistances of immobilized carrier in both reactors. Apparent $K_m$ decreased with increasing dilution rate in FBR but showed a constant value above $0.4h^{-1}$ of dilution rate in CSTR. The experimental results in FBR showed nearly analogous to those in CSTR, however, the performance of FBR resulted in lower hydrogen productivity and an external effectiveness factor but a higher internal effectiveness factor than in CSTR. The overall effectiveness factor obtained with various input 91ucose concentrations showed similar values in both reactors.

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Estimation of Dilution Factor between Two Soil Salinity Analysis Methods (두 가지 토양 염도 측정법간의 환산계수 추정)

  • Lee, Seung-Heon;Hong, Byeong-Deok;An, Yeul
    • Proceedings of the Korean Society of Agricultural Engineers Conference
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    • 2002.10a
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    • pp.405-408
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    • 2002
  • The electrical conductivity, EC is a major indicator of soil salinity. Measuring EC of saturation-paste extract of soil, ECe, is the standard way to evaluate soil salinity. However much of the data on soil salinity have been obtained by measuring the EC of the 1:5 soil-to-water extract, EC(1:5) or salts contents(%) which multiplied by conversion factor. And, thus we attempted to collect and analysis 90 soil samples at 9 reclaimed tidelands in Korea and to derive a relationship between ECe and dilution factor at ECe and EC(1:5), $DF_{1:5}$ of 3 soil textural conditions and 6 salinity conditions. Regression equations between ECe and $DF_{1:5}$ were obtained $ECe=1.4701ln(DF_{1:5})+5.0974(r^2=0.97^{**})$ in case of more than 50% silt contents, $ECe=2.1399ln(DF_{1:5})+5.3462 (r^2=0.99^{***})$ in case of below 50% silt contents, and $ECe=1.5927ln(DF_{1:5})+5.2486 (r^2=0.98^{***})$ in all cases, and then we suggested the $DF_{1:5}\;and\;DF_%$ of 3 soil textural conditions and 6 salinity conditions.

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Analysis of Toxic-PCBs in Sediment by Isotope Dilution HRGC/HRMS (Isotope Dilution HRGC/HRMS 방법을 이용한 저니토중 Toxic-PCBs 분석)

  • Jang, Seong-Ki;Choi, Duk-Il;Park, Sun-Ku;Kim, Kyung-Sup
    • Analytical Science and Technology
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    • v.12 no.6
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    • pp.550-557
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    • 1999
  • This Analysis was conducted for 13 toxic-PCBs having TEF value among 209 PCBs isomers in sediment by isotope dilution HRGC/HRMS method. From the result, the recovery of surrogate standard was in the range of 71~99%. The concentration range for 13 toxic-PCBs in sediment was found to be 0.84~2.49 ng/g, among them the concentration levels of 2,2',3,3',4,4',5-HpCB(IUPAC No. 170) and 2,2',3,4,4',5,5'-HpCB(IUPAC No. 180) represented almost 50% of total concentrarion and that of 2,3,4,4,5-PeCB(IUPAC No. 114) showed over 10%. The TEQ concentration levelwas in the range of 0.38~2.63 pg-TEQ/g and 3,3',4,4',5-PeCB(IUPAC No. 126) concentration represented over 50% of total TEQ concentration.

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