• Korean Journal of Food Science and Technology
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• v.35 no.2
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• pp.297-301
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• 2003

An inhibitor of squalene synthase, a key enzyme in the cholesterol biosynthetic pathways and a target for improved agents to lower plasma levels of low-density lipoprotein, was sequentially purified from Curcuma longa by acetone extraction, silica gel column chromatography, and sephadex LH-20 column chromatography. Active compound, YUF-01, was successfully purified and analyzed as $C_{20}H_{21}O_6$ by electron ionization mass spectrum. Through $^1H-NMR$ and $^{13}C-NMR$ analyses, YUF-01 was identified as curcumin, which showed strong inhibition of squalene synthase.

• Applied Chemistry for Engineering
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• v.31 no.5
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• pp.520-525
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• 2020

In this study, we developed a machine learning-based model for predicting the production stage temperature of distillation process. It is necessary to predict an accurate temperature for control because the control of the distillation process is done through the production stage temperature. The temperature in distillation process has a nonlinear complex relationship with other variables and time series data, so we used the recurrent neural network algorithms to predict temperature. In the model development process, by adjusting three recurrent neural network based algorithms, and batch size, we selected the most appropriate model for predicting the production stage temperature. LSTM₁₂₈ was selected as the most appropriate model for predicting the production stage temperature. The prediction performance of selected model for the actual temperature is RMSE of 0.0791 and R² of 0.924.

• Journal of Ocean Engineering and Technology
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• v.16 no.3
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• pp.19-27
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• 2002

The motion of a floating OWC chamber in waves is studied taking account of fluctuating air pressure in the air chamber. An atmospheric pressure drop occurs across the upper opening of the chamber which causes not only hydrodynamic but also pneumatic added mass and damping forces to the floating chamber. A velocity potential in the water due to the free surface oscillating pressure patch is added to the conventional radiation-diffraction potential problem. the potential problem inside the chamber is formulated by making use of the Green integral equation associated with the Rankine Green function wile the outer problem with the Kelvin Green function. The two integral equations are solved simultaneously by making use of a matching boundary condition at the lower opening of the chamber to the outer water region. The chamber motion in the frequency domain is calculated for various values of parameters related to the atmospheric pressure drop. The present methods can also be sued for the analysis of air-cushion vehicle motion as well as for the design of a floating OWC wave energy absorber.

• Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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• 2002.05a
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• pp.191-197
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• 2002

The motion of a floating OWC chamber in waves is studied taking account of fluctuating.air pressure in the air chamber. An atmospheric pressure drop occurs across the upper opening of the chamber which causes not only hydrodynamic but also pneumatic added mass and damping forces to the floating chamber. A velocity potential in the water due to the free surface oscillating pressure patch is added to the conventional radiation-diffraction potential problem. The potential problem inside the chamber is formulated by making use of the Green integral equation associated with the Rankine Green function while the outer problem with the Kelvin Green function. The two integral equations are solved simultaneously by making use of a matching boundary condition at the lower opening of the chamber to the outer water region. The chamber motion in the frequency domain is calculated for various values of parameters related to the atmospheric pressure drop. The present methods can also be used for the analysis of air-cushion vehicle motion as well as for the design oj a floating owe wave energy absorber.

• Natural Product Sciences
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• v.10 no.1
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• pp.29-31
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• 2004

A new method for the quantitative determination of fucosterol in the marine algae Pelvetia siliquosa by gas chromatography was established. A HP-1 column programmed as $200^{\circ}C\;(5\;min)\;{\rightarrow}\;5/min\;{\rightarrow}\;280^{\circ}C\;(10\;min)$ was developed. The analysis of fucosterol in P. siliquosa was successfully carried out within 30 min.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2012.05a
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• pp.339-340
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• 2012

Green frame is combined by structural steel and reinforcements of Green column and beam and unified by cast-in-place concrete. However, when upper reinforcements penetrate structural steel hole, the execution is difficult due to interference of joint and a rib of deformed reinforcements. Therefore, the objective of this study is to propose the reinforcement tools to improve productivity of precast structure connection construction. The reinforcement tools proposed in this study can be helpful to improve constructability, safety, duration, and cost comparing with conventional reinforcement method since unskilled workers can deal with reinforcements easily.

• Journal of Microbiology and Biotechnology
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• v.11 no.3
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• pp.497-503
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• 2001

The purpose of this study was to examine the efficacy and mechanism of the cryo-precipitation, solvent/detergent (S/D) treatment, monoclonal anti-FVIIIc antibody (mAb) column chromatography, Q-Sepharose column chromatography, and lyophilization involved in the manufacture of antithemophilic factor VII(GreenMono) from human plasma, in the removal and/or inactivation of blood-borne viruses. A variety of experimental model viruses for human pathogenic viruses, including the bovine viral diarrhoea virus (BVDV), bovine herpes virus (BHV), murine encephalomyocarditis virus (EMCV), and porcine parvovirus (PPV), were all selected for this study. BHV and EMCV were effectively partitioned from a factor VII during the cryo-precipitation with a log reduction factor of 2.83 and 3.24, respectively. S/D treatment using the organic solvent, tri(n-butyl) phosphate (TNBP), and the detergent, Triton X-100, was a robust and effective step in inactivating enveloped viruses. The titers of BHV and BVDV were reduced from the initial titer of 8.85 and $7.89{log_10} {TCID_50}$, respectively, reaching undetectable levels within 1 min of the S/D treatment. The mAb chromatography was the most effective step for removing nonenveloped viruses, EMCV and PPV, with the log reduction factors of 4.86 and 3.72, respectively. Q-Sepharose chromatography showed a significant efficacy for partitioning BHV, BVDV, EMCV, and PPV with the log reduction the log reduction factors of 2.32, 2.49, 2.60, and 1.33 respectively. Lyophilization was an effective step in inactivating g nonenveloped viruses rather than enveloped viruses, where the log reduction factors of BHV, BVDV, DMCV, and PPV were 1.41, 1.79, 4.76, and 2.05, respectively. The cumulative log reduction factors of BHV, BVDV, EMCV, and PPV were ${\geqq}$11.12, ${\geqq}$7.88, 15.46, and 7.10, respectively. These results indicate that the production process for GreenMono has a sufficient virus-reducing capacity to achieve a high margin of the virus safety.

• Journal of Microbiology
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• v.38 no.3
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• pp.187-191
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• 2000

A validation study was conducted to determine the efficacy of solvent/Detergent (S/D) inactivation and Q-Sepharose column chromatographic removal of the human immunodeficiency virus (HIV) during the manufacturing of a high purity antihemopilic factor VIII (GreenMono) from human plasma. S/D treatment using the organic solvent, tri (n-butyl) phosphate, and the detergent, Trition X-100, was a robust and effective step in eliminating HIV-1. The HIV-1 titer was reduced from an initial titer of 8.3 log10 TCID50 to undetectable levels within one minute of S/D treatment, HIV-1 was effectively partitioned form factor VIII during Q-Sepharose column chromatography with the log reduction factor of 4.1 . These results strongly assure the safety of GreenMono From HIV.

• Food Science and Biotechnology
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• v.14 no.3
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• pp.344-349
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• 2005

Aldose reductase catalyzes the conversion of glucose into sorbitol. Inhibiting this enzyme in diabetes mellitus can delay or prevent pathogenic process. Aldose reductase inhibitor was screened from Korean fermented soybean pastes (Doen-jang) and purified via sequential processes of ethanol extraction, HP-20 column chromatography, ethyl acetate extraction, silica gel column chromatography, and crystallization. Aldose reductase inhibitor was identified as genistein with molecular weight of 270 Da and molecular formula of $C_{15}H_{10}O_5$ based on UV spectrometry, $^1H$ and $^{13}C\;NMRs$, and mass spectrometry. Genistein inhibited aldose reductase of pig lens with $IC_{50}$ level of $20\;{\mu}M$. Because genistein was effective against aldose reductase of animal source, it may be a potential therapeutic agent for diabetic complications.

• Korean Journal of Food Science and Technology
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• v.53 no.5
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• pp.553-560
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• 2021

Theanine, the major amino acid and a sweet umami component of green tea, has anti-stress effects in humans. From green tea, theanine was extracted at 80℃ for 2 h using a low temperature, high pressure extractor, and caffeine was removed using an HP-20 column with 80% ethanol. Theanine extracts were applied to produce functional jelly using three kinds of gelling agents (I, II, and III) or various concentrations of theanine extracts (10-50%). Theanine jelly was characterized with respect to its physical properties, product stability, and physiological function. Gelling agent III (tamarind gum, xanthan gum, and locust bean gum=2:3:5, w/w/w) and S3 (35% theanine extracts) jelly exhibited the optimum textural properties with lower hardness and high springiness. Among theanine jellies, S3 exhibited optimum product stability, high 1,1-diphenyl-2-picrylhydrazyl (DPPH) scavenging, and acetylcholinesterase inhibitory activity. These results indicate that the anine extracts could be used as a neuroprotective source in the food industry.