• Journal of the Korean Society of Food Science and Nutrition
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• v.22 no.6
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• pp.833-838
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• 1993

A strain of Penicillium sp. extracellularly produced an inhibitory substance for lipoxygenase. These purification procedures were followed : ethanol treatment, chromatographies on Dowex 50W, Sephadex G-25, silica gel column and HPLC. The inhibitor was stable in pH range from 3.0 to 5.0 at $25^{\circ}C$, and a treatment at 10$0^{\circ}C$ for 2 hours didn't diminish its original activity. The purified inhibitor was charred at temperature near 22$0^{\circ}C$~23$0^{\circ}C$ and decomposed. Molecular weight of the inhibitor was estimated to be approximately 270 by Sephadex G-25 column chromatography. The inhibitor rapidly formed EI complex with lipoxygenase and inhibited enzyme activity.

• Microbiology and Biotechnology Letters
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• v.44 no.3
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• pp.333-340
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• 2016

An alkaline protease was purified and characterized from an alkalophilic microorganism, Bacillus sp. DK1122, isolated from soil in central Korea. The optimum temperature and pH for the growth of the producer strain were 40℃ and pH 9.0, respectively. The protease was produced aerobically at 40℃ after 24 h incubation in modified Horikoshi I medium (pH 9.0) containing 0.5% (w/v) glucose, 0.8% (w/v) yeast extract, 0.5% (w/v) polypeptone, 0.1% (w/v) K₂HPO₄, 0.02% (w/v) MgSO₄·7H₂O, 1% (w/v) Na₂CO₃, and 3% (w/v) NaCl. The alkaline protease was purified by 70% ammonium sulfate precipitation of the culture supernatant of Bacillus sp. DK1122, followed by CM-Sepharose chromatography. The molecular weight of the enzyme was estimated to be 27 kDa on the basis of SDS-PAGE. The optimum temperature and pH for the protease activity were 60℃ and pH 9.0, respectively. Addition of CaCl₂ increased the thermal stability of the purified protease, where 90% of protease activity was retained at 60℃ for up to 3 h. Consequently, it is expected that the alkaline protease from this study, exhibiting stability at pH 7–9 and 60℃, may be promising for application in the food and detergent industries.

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.3
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• pp.355-359
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• 2014

The objective of this study was to determine the hyperglycemic effects of mineral-rich salt in type 2 diabetic Goto-Kakizaki (GK) rats and normal Wistar rats. Animals were divided into five groups, including a normal group, fed three different experimental salts [purified salt (PS), mineral-rich salt (WS1 and WS2), and bamboo salt (BS)] in the form of 1% salt solution for 12 weeks. Liver, kidney, and spleen weights were significantly increased in GK rats of salt groups as compared to Wistar normal group without salt. However, there was no difference among the salt groups. For serum lipids, total cholesterol level in the BS group and triglyceride level in the WS group were significantly reduced compared to those of the PS group. The concentration of blood glucose in the GK-PS group increased continuously during the experimental period, whereas that in the GK-WS group was significantly reduced at 12 weeks. In GK rats, glucose levels among the salt groups in OGTT by glucose were not significantly different compared to normal rats. Insulin and glucagon levels in blood were not significantly different among the groups, and no such association was observed for insulin. Pancreatic lslets of Langerhans in the PS group showed irregular formation compared to those of the normal, WS, and BS groups.

• Proceedings of the Korean Information Science Society Conference
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• 2000.10a
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• pp.439-441
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• 2000

절차지향 소프트웨어를 객체지향 소프트웨어로의 재공학은 소프트웨어 유지.보수 비용의 절감과 기존의 시스템에 새로운 요구사항을 수용하는 등 많은 장점이 있다. 본 논문은 절차지향 소프트웨어를 재공학하는 과정에서 안전한 지속성(Safe Persistency) 결정문제, 즉 객체의 생성과 생성 주기의 결정 방법을 제안하였다. 본 논문에서는 지속성 결정을 위해 다섯 단계의 모델링 과정을 제시하였으며 모델링 과정을 통해 객체의 정확한 생성과 소멸 시점을 추출하였고 정제 과정을 거침으로써 메시지 전달과 생성/소멸 과정에서 안정성과 일관성을 유지할 수 있도록 하였다.

• Proceedings of the Materials Research Society of Korea Conference
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• 2002.05a
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• pp.44-44
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• 2002

• Microbiology and Biotechnology Letters
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• v.38 no.1
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• pp.84-92
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• 2010

Antibacterial compound from Bacillus subtilis MJP1 was purified using C18 Sep-Pak cartridge, ion exchange chromatography, and gel filtration chromatography. The purified antibacterial compound showed antibacterial activity against Listeria monocytogenes, Bacillus subtilis, Staphylococcus aureus subsp. aureus, and Enterococcus faecalis. The purified antibacterial compound was found to be stable at $100^{\circ}C$ for 5 min and in the pH range of 3.0~9.0, but it was unstable at pH 10.0. It was inactivated by proteinase K and pronase E, and heat treatment at $121^{\circ}C$ for 15 min, but it was stable with lipase and $\alpha$-amylase treatment, which indicated its proteineous nature. Ultra performance liquid chromatography and electrospray ionization tandem mass spectrometry analysis were used to identify the purified antibacterial compound and confirmed the existence of two peptides (3356.54 Da, 3400.5244 Da).

• Proceedings of the Korean Institute of Building Construction Conference
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• 2014.05a
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• pp.146-147
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• 2014

In this study, as the resistance of the carbonation for high volume admixture incorporating concrete, coating effect of using refined cooking oil in the surface of high volume admixture incorporating concrete has been tested. The following results could be made as the conclusion. For the fresh concrete, the slump and air content has been identified as satisfying the target range. For the hardened concrete, comparing with specimen of Plain, specimen with coating showed better long age compressive strength. For the carbonation speed, the specimen of FA30 showed highest speed and the specimen of BS60 showed higher speed than specimen of Plain. For all the specimens coated with RCO, as the decrease of capillary pores inside the concrete, the carbonation speed has been obviously decreased and with even better effect than using PEP coating. It could be identified that specimens with coating by RCO showed good effect on refrain the speed of carbonation.

• Proceedings of the Korean Information Science Society Conference
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• 1999.10c
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• pp.256-258
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• 1999

본 논문에서는 DS-CDMA 시스템에서 예약 기반 MAC 플로토콜의 성능을 분석한다. 본 논문에서 고려하고 있는 예약 기반 MAC 프로토콜은 NAK 방식과 Request 큐잉 방식이다. NAK 방식은 예약 요구를 수락할 수 없는 경우에 NAK를 전송하여 전송 불가를 통지하는 방식이며, Request 큐잉 방식은 예약 요구를 수락할 수 없을 경우에 기지국에 예약 요구 패킷을 저장하는 방식이다. 그리고 이러한 두 방식에 채널 유지 기능을 추가한 방식을 함께 고려한다. 각 방식에서 패킷의 길이를 변화시키면서 수율과 평균 전달 지연 시간을 비교하였다. 성능 분석 결과 패킷의 길이가 짧은 경우에는 예약 방식의 성능이 매우 낮으며, 패킷의 길이가 길어지면 성능이 향상되는 것을 알 수 있다. 그리고 채널 유지 기능을 추가함으로서 전반적인 성능이 향상되며, 채널 유지 방식에서는 패킷간의 도착 시간, 예약 과정의 지연 시간 등을 고려해서 최적의 채널 유지 시간을 설정해야 함을 알 수 있다.

• KSBB Journal
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• v.15 no.1
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• pp.42-48
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• 2000

Urokinase (UK), a thrombolytic enzyme used to clear catheters obstructed by blood clots, can be also used industrially in the recombinant protein purification system to cleave a fusion protein linked with a certain fragment of GST. We have immobilized UK by covalent attachment to activated Sepharose 6B-Cl gels and evaluated its performance to cleave a fusion protein of hGH and GST. The Sepharose gels were activated by etherification with glycidol (2,3-epoxypropanol) and further oxidized with periodate resulting in glyceryl-Sepharose gels. After the activation treatment, surface density of the aldehyde groups was 7-30 $\mu$mol-aldehde/mL-gel. Immobilization yield was higher than 99% at high pH (10.5), and the immobilized UK maintained ca. 80% specific activity of the soluble UK. In a column reaction the cleavage yield heavily depended on the feed rate, and it was nearly 86% of that from soluble UK. And the immobilized UK was successfully regenerated by unfolding and refolding with 6M GuHCl. After cleavaging reaction, the monomeric hGH was purified by using expanded bed adsorption chromatography.

• Analytical Science and Technology
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• v.29 no.4
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• pp.194-201
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• 2016

The stability comparison tests on purified bee venom (PBV) and bee venom melittin (BVM) in different conditions of temperature, solvent, and concentration were studied. High purity BVM (98.2 %) was separated from PBV by prep-HPLC (column, C₄) and used to stability tests in aqueous phase. The stability of the PBV has been increased in the saline solution, while BVM was reduced. In distilled water, the stability of PBV has been reduced, while BVM showed an increasing result. As a result, the appropriate conditions for maintaining the long term stability of BVM were found to be the low temperature (4 ℃), distilled water, and concentration (1.0 mg/mL).