• Title/Summary/Keyword: incubation time and temperature

Search Result 254, Processing Time 0.026 seconds

A Study on the Antimicrobial Effect of Garlic Extract using Super-Critical Carbon Dioxide (초임계 이산화탄소를 이용한 마늘 추출물의 항균효과에 관한 연구)

  • Sung, Ki-Chun
    • Journal of the Korean Applied Science and Technology
    • /
    • v.20 no.1
    • /
    • pp.51-56
    • /
    • 2003
  • Garlic extract using super-critical carbon dioxide is influenced by temperature and pressure, and the optimum condition can make under super-critical state. We can know the defects in process of super-critical extration, It can indicate the drop of product rate, energy loss and equipment expense etcs. The minimum inhibition concentration of microbe which garlic extract contains has apperared the concentration more than 800ppm in this experiment. According to the result of this experiment, we can know that the antibiosis effect in the microbe of staphylococcus and fungus has disappeared in the incubation time more than 12 hours.

Synthesis of MnFeP1-xAsx Nanocrystalline Powders by High-Energy Ball Milling (고에너지볼밀링을 이용한 MnFeP1-xAsx 나노분말의 합성)

  • 조영환
    • Journal of Powder Materials
    • /
    • v.10 no.2
    • /
    • pp.129-135
    • /
    • 2003
  • Nanocrystalline powders of $MnFeP_{1-x}As_x$(x=0.45-0.6) have been synthesized by mechanochemical reaction at room temperature using high-energy ball milling from mixtures of Mn, Fe, P, and As Powders. It has been found that a mechanically induced self-propagating reaction (MSR) occurs within 2 hours of milling and it produces very fine polycrystalline powder having a hexagonal $Fe_2P$ structure. Further milling up to 24 hours did not change the crystalline and average particle sizes or the phase composition of the milling product. When x is 0.65, no reaction among the reactants has been observed even after 24 hours of milling. As the P content decreases in $MnFeP_{1-x}As_x$, the incubation time for the MSR has increased and the lattice constants in both a and c axes have changed.

Optimization of Culture Conditions and Bench-Scale Production of $_L$-Asparaginase by Submerged Fermentation of Aspergillus terreus MTCC 1782

  • Gurunathan, Baskar;Sahadevan, Renganathan
    • Journal of Microbiology and Biotechnology
    • /
    • v.22 no.7
    • /
    • pp.923-929
    • /
    • 2012
  • Optimization of culture conditions for L-asparaginase production by submerged fermentation of Aspergillus terreus MTCC 1782 was studied using a 3-level central composite design of response surface methodology and artificial neural network linked genetic algorithm. The artificial neural network linked genetic algorithm was found to be more efficient than response surface methodology. The experimental $_L$-asparaginase activity of 43.29 IU/ml was obtained at the optimum culture conditions of temperature $35^{\circ}C$, initial pH 6.3, inoculum size 1% (v/v), agitation rate 140 rpm, and incubation time 58.5 h of the artificial neural network linked genetic algorithm, which was close to the predicted activity of 44.38 IU/ml. Characteristics of $_L$-asparaginase production by A. terreus MTCC 1782 were studied in a 3 L bench-scale bioreactor.

Non-invasive Transcutaneous pCO2 Gas Monitoring System for Arterial Blood Gas Analysis

  • Bang, Hyang-Yi;Kang, Byoung-Ho;Eum, Nyeon-Sik;Kang, Shin-Won
    • Journal of Sensor Science and Technology
    • /
    • v.20 no.5
    • /
    • pp.311-316
    • /
    • 2011
  • Monitoring the carbon dioxide concentration in arterial blood is vital for the evaluation and prevention of pulmonary disease. Yet, domestic pure arterial blood carbon dioxide sensor technologies are not being developed, instead all sensors are imported. In this paper, we develop a real time monitoring system for arterial blood partial pressure of carbon dioxide($pCO_2$) gas from the wrist by using a carbon micro-heater. The micro-heater was fabricated with a thickness of 0.3 ${\mu}m$ in order to collect the carbon dioxide under the skin. The micro-heater has been designed to perform temperature compensation in order to prevent damage to the skin. Two clinical trials of the system were undertaken. As a result, we demonstrated that a portable, transcutaneous carbon dioxide analysis($TcpCO_2$) device produced domestically is possible. In addition, this system reduced the analysis time significantly. Carbon films could reduce the unit price of these sensors by replacing the gold film used in foreign models. Also, we developed a real time monitoring system which can be used with optical biosensors for medical diagnostics as well as gas sensors for environmental monitoring.

Effects of Temperature on the Development of Chinese Windmill Butterfly, Atrophaneura alcinous (Lepidoptera: Papilionidae)

  • Kim, Seong-Hyun;Hong, Seong-Jin;Park, Hae-Chul;Lee, Young-Bo;Kim, Nam Jung
    • International Journal of Industrial Entomology and Biomaterials
    • /
    • v.25 no.2
    • /
    • pp.159-162
    • /
    • 2012
  • The Chinese windmill butterfly, Atrophaneura alcinous, is an important butterfly for exhibition in butterfly garden. The objective of this study was to determine the effect of temperature on A. alcinous in the laboratory. Development of A. alcinous reared on leaves of Aristolochia contorta was investigated at five constant the laboratory condition (20, 22.5, 25, 27.5 and $30^{\circ}C$) and at relative humidity of 60% with a photoperiod of 14:10 (L:D). Temperatures have been suggested as an important determinant of developmental rate, lifespan and mortality in invertebrates. As the temperature increased, the length of the developmental period gradually decreased. The developmental time (pupation) from egg hatching to pupation was respectively 25.8, 23.6, 19.6, 15.5, and 12.9 days at the temperatures of 20, 22.5, 25, 27.5 and $30^{\circ}C$. And pupation was respectively 40.0, 30.0, 63.4, 50.0, 23.3% at the temperatures of 20, 22.5, 25, 27.5 and $30^{\circ}C$. The developmental threshold temperature estimated for egg-to-pupae was 10.8, with a thermal constant of 230.4 degree-days. Therefore, the optimal developmental temperature for A. alninous was determined to be $25^{\circ}C$. To compare the effects of the total duration of chilling on the termination of diapause, larvae were subjected to a temperature of $8^{\circ}C$ from 60 to 120 days. The rate of termination of diapause was significantly higher at 60 days compared to other incubation period.

A Study on the Saturation of Grain Size in Pb(Zr, Ti)$O_3$ Thin Films (Pb(Zr, Ti)$O_3$ 박막에서 결정립 크기 포화 현상에 관한 연구)

  • 이장식;김찬수;주승기
    • Journal of the Korean Ceramic Society
    • /
    • v.37 no.6
    • /
    • pp.530-536
    • /
    • 2000
  • During the grain growth of the PZT thin films by selective nucleation method using PZT seed, it was found that the grain size was saturated with the annealing temperature. The saturation of grain size was analyzed by the interfacial energy which appeared during the crystallization. The factors affecting the saturation of grain size were found to be the interfacial energy between perovskite phase and pyrochlore phase, and PZT thin film and the bottom Pt electrode. When the ion damage was introduced to the grain-size saturated PZT thin films, further lateral growth was observed. Pt bottom electrode thickness was changed to control the interfacial energy between the PZT thin film and the Pt bottom electrode. When Pt thickness was increased, the grain size was also increased, because the lattice parameter of Pt films was increased with the thickness of the Pt films. The incubation time of nucleation was increased with the amount of the ion damage on the Pt films.

  • PDF

The Bactericidal Effect of High Temperature Is an Essential Resistance Mechanism of Chicken Macrophage against Brucella abortus Infection

  • Arayan, Lauren Togonon;Reyes, Alisha Wehdnesday Bernardo;Hop, Huynh Tan;Xuan, Huy Tran;Baek, Eun Jin;Min, Wongi;Kim, Suk
    • Journal of Microbiology and Biotechnology
    • /
    • v.27 no.10
    • /
    • pp.1837-1843
    • /
    • 2017
  • Knowledge of avian host responses to brucellosis is critical to understanding how birds resist this infection; however, this mechanism is not well established. On the other hand, temperature has a major involvement in the physiology of living organisms, and cell death induced by heat is attributed to protein denaturation. This study demonstrates the direct bactericidal effect of a high temperature ($41^{\circ}C$) on Brucella abortus that resulted in the gradual reduction of intracellular bacteria and inhibited bacterial growth within avian macrophage HD11 in an increasing period of time. On the other hand, this study also revealed that high temperature does not affect the rate of bacterial uptake, as confirmed by the bacterial adherence assay. No significant difference was observed in the expression of target genes between infected and uninfected cells for both temperatures. This study suggests the susceptibility of B. abortus to bacterial death under a high temperature with an increased period of incubation, leading to suppression of bacterial growth.

Solid Phase Crystallization of LPCVD Amorphous Silicon Thin Films by Alternating Magnetic Flux (교번자속인가에 의한 비정질 실리콘 박막의 결정화거동에 대한 연구)

  • 송아론;박상진;박성계;남승의;김형준
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
    • /
    • 2000.11a
    • /
    • pp.459-462
    • /
    • 2000
  • A new method for the fabrication of poly-Si films is reported using by alternating magnetic flux crystallization (AMFC) of LPCVD a-Si films. In this work we have studied the crystallization of LPCVD a-Si films by alternating magnetic flux. A-Si films were 1200$\AA$-thick deposited at 48$0^{\circ}C$ at a total pressure of 0.25Torr using Si$_2$H$_{6}$/H$_2$. After this step, these a-Si films were thermally annealed by Alternating Magnetic Flux at 43$0^{\circ}C$ for 1hours. The annealed films were characterized using X-ray diffraction (XRD), Raman Spectra, Atomic Force Microscopy(AFM). Both alternating magnetic flux crystallization and solid phase crystallization were investigated to compare enhanced crystallization a-Si. We have found that the low temperature crystallization method at 43$0^{\circ}C$ by alternating magnetic flux.x.

  • PDF

Optimization of $\beta$-Galactosidase Production in Stirred Tank Bioreactor Using Kluyveromyces lactis NRRL Y-8279

  • Dagbagh, Seval;Goksungur, Yekta
    • Food Science and Biotechnology
    • /
    • v.18 no.6
    • /
    • pp.1342-1350
    • /
    • 2009
  • This paper investigates the production and optimization of $\beta$-galactosidase enzyme using synthetic medium by Kluyveromyces lactis NRRL Y-8279 in stirred tank bioreactor. Response surface methodology was used to investigate the effects of fermentation parameters on $\beta$-galactosidase enzyme production. Maximum specific enzyme activity of 4,622.7 U/g was obtained at the optimum levels of process variables (aeration rate 2.21 vvm, agitation speed 173.4 rpm, initial sugar concentration 33.8 g/L, incubation time 24.0 hr). The optimum temperature and pH of the $\beta$-galactosidase enzyme produced under optimized conditions were $37^{\circ}C$ and pH 7.0, respectively. The enzyme was stable over a pH range of 6.0-7.5 and a temperature range of $25-37^{\circ}C$. The $K_m$ and $V_{max}$ values for O-nitrophenol-$\beta$-D-galactopyranoside (ONPG) were 1.20 mM and $1,000\;{\mu}mol/min{\cdot}mg$ protein, respectively. The response surface methodology was found to be useful in optimizing and determining the interactions among process variables in $\beta$-galactosidase enzyme production. Hence, this study fulfills the lack of using mathematical and statistical techniques in optimizing the $\beta$-galactosidase enzyme production in stirred tank bioreactor.

Cultural Characteristics and Fruiting-body Productivity of New Cultivar 'Hwadam' (Lentinula edodes) by Punching Treatments on the Sawdust Medium (톱밥배지 침공처리에 따른 표고 '화담' 의 균사배양 및 자실체 생산성)

  • Kim, Jeong-Han;Choi, Jun-Yeong;Kim, Yeon-Jin;Mun, Ji-Young;Ha, Tai-Moon;Jung, Gu-Hyun
    • The Korean Journal of Mycology
    • /
    • v.49 no.3
    • /
    • pp.295-302
    • /
    • 2021
  • The effect of punching treatment on bags containing sawdust medium for the stable production of fruiting bodies of Lentinula edodes 'Hwadam' was investigated. After spawn inoculation, the sawdust medium temperature and CO2 concentration reached 27.0-28.8℃ on the 23rd day of incubation, and 14.0-15.6% on the 16th day of incubation, respectively, decreasing thereafter. The O2 concentration showed an opposite pattern to the CO2 concentration. As the number of punching treatments on the medium increased during the incubation period, the lightness value decreased, and conversely, the color difference and weight loss rate increased. There was no difference in the cultivation period according to the punching treatment. As the punching treatment increased on the sawdust medium, the fruiting body yield increased; a three-time punching treatment produced the best yield with 605.7 g. Thus, proper punching treatment on a sawdust medium during the incubation period can increase the number of fruiting bodies and yield.