• 수산해양교육연구
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• 제10권2호
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• pp.184-210
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• 1998

The set-net fishing is involved in the trap fishing method that intercepts the fishes migrating along the coast and induces them to be in the bag net stretched in advance. And this fishing also corresponds to the licensed fishing in fisheries law. Though its annual total production of around 50,000 to 70,000 M/T is less than in other fishery section, its price becomes higher because the fishes are sold in the live fish condition. Until recently, the set-net fishing is one of the preferred fisheries on account of its less operation expense and stably operating condition in a long term. In the meantime, the industrialization in Korea having been prospered along coastal area and the over fishing in terms of the powered and larger size fishing boat make the fishing ground environment worse yearly. In addition, its difficulty becomes more worse with issuing fishery product free import in July 1997; accordingly, the strategy for the set-net fishing through business rationalization should be considered. From the discussion of the sort of set-net, general present situation and operating actual state of set-net fishing, the improved methods for business rationalization in the present paper is proposed as follows: 1. to increase the fisheries resource through prevention of the marine contamination and purification of coastal area environment. 2. to save the labour cost through the improved the fishing gear. 3. to improve the fish quality through development of the process technology. 4. to increase the income of fishers through improvement of the distribution channels.

• 청정기술
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• 제11권4호
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• pp.171-179
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• 2005

바이오디젤은 동물성 또는 식물성 유지를 알코올과 반응시켜 생성된 물질로서 경유와 유사한 특성을 가지고 있어 기존 제품에 혼합하여 연료로 사용하고 있으며 대기오염을 감소시키는 효과와 재생 가능한 바이오매스로부터 생산된다는 장점을 가지고 있다. 기존의 알칼리 또는 산성 촉매를 사용하는 공정에 비하여 초임계 상태의 메탄올을 사용하여 바이오디젤을 제조하는 공정은 반응시간이 짧고 촉매를 사용하지 않아 분리/정제 공정이 단순하여 경제적이기 때문에 최근 많은 연구가 진행되고 있다. 특히, 국내의 경우 연간 20만톤의 폐식용유가 발생하고 있기 때문에 이의 재활용 방안으로 국내 고유의 초임계 공정이 상업화 될 경우 막대한 에너지 회수와 이산화탄소 저감 그리고 환경 개선 효과를 기대할 수 있을 것으로 사료된다.

• 약학회지
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• 제37권2호
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• pp.129-135
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• 1993

Serratia sp. Y-4 was isolated from soil. Many characteristics of the strain and optimum cultivation condition for protease production were investigated.,The protease from Serratia sp. Y-4 was purified and studied for the properties of the enzyme. The isolated strain was identified to the genus Serratia. The strain was cultivated in 1%-casein, 0.5%-Na$_{3}$PO$_{4}$.7H$_{2}$O, 0.1%-NaCl, 0.05%-KCI, 0.02%-MgSO$_{4}$.7H$_{2}$O, 0.02%-CaCl$_{2}$.2H$_{2}$O, 0.02%-ZnSO$_{4}$.7H$_{2}$O, 0.02%-MnCl$_{2}$.4H$_{2}$O and 0.5%-soy bean oil at pH 7.0 for 35 hrs. The enzyme was purified about 5.89 fold from the culture broth with 31.1% recovery and 19,613 u/mg through ultrafiltration, ammonium sulfate, DEAE-sephacel and Superose-12 chromatography. The purified enzyme was identified as one band by isoelectric focusing, SDS- and native-PAGE. It has maxium activity at $37^{\circ}C$ and pH 9.0. Molecular weight of it is approx. 50 kD and pl is about 6.70. Its Km value for casein was 20 mg/ml. 5 mM-EDTA, 5mM-SDS, Ag$^{+1}$, Cu$^{+2}$, Hg$^{+2}$ and Pb$^{+2}$ inhibited the enzyme.

• KSBB Journal
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• 제10권3호
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• pp.343-348
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• 1995

LeI은 스테로이드를 통울에 투여하였을 때 분비가 촉진되어 항염증성 효과를 나타내는 calcium 의 존성 phospholipid 결합 단백질이다. S. cerevisiae는 대장균과 통물세포의 장점을 모두 가지고 있으므로 동물세포 유래의 이종 단백질의 분비 생산에 많이 이용되고 있다. 본 연구에서는 GAL10 promoter­p ppL-LCI유전자 LCI terminator로 구성된 pYGLPT5 로 LCI을 S. cerevisiae SEY2102에서 발현 분비시키고 각 분획으로 나누어 LCI양을 비교한 결과 protoplast 68.6 %. periplasmic 24 %, culture supernatant 7.4%로 분포하였다. pYGLPT5로 형질전환된 S. cereviswe 2102를 유가 배양한 결과, 최종적인 LCI의 생산량은 약 $500mg/\ell$ 였다. LCI은 N 말단 부근에 $CA^{++}$ 결합부위가 있으므로 이를 이용하여 hydroxylapatite column chromatography로 정 제하 였다. 배지로 분비된 34kDa LCI을 ultrafiltration 과 hydroxylapatite column chromatography 의 두 단계로 순도 99% 이상으로 정제할 수 있었다.

• Journal of Microbiology and Biotechnology
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• 제17권5호
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• pp.728-732
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• 2007

In the present article, a novel fusion expression vector for Escherichia coli was developed based on the pTORG plasmid, a derivative of pET32a. This vector, named pT7MT(GenBank Accession No DQ504436), carries a T7 promoter and it drives the downstream gene encoding Metallothionein 2A(MT2A). There are in-framed multiple cloning sites(MCS) downstream of the MT2A gene. A target gene can be cloned into the MCS and fused to the C-terminal of the MT2A gene in a compatible open reading frame(ORF) to achieve fusion expression. The metal-binding capability of MT2A allows the purification of fusion proteins by metal chelating affinity chromatography, known as $Ni^{2+}$-affinity chromatography. Using this expression vector, we successfully got the stable and high-yield expression of MT2A-GST and MT2A-Troponin I fusion proteins. These two proteins were easily purified from the supernatant of cell lysates by one-step $Ni^{2+}$-affinity chromatography. The final yields of MT2A-GST and MT2A-Troponin I were 30mg/l and 28mg/l in LB culture, respectively. Taken together, our data suggest that pT7MT can be applied as a useful expression vector for stable and high-yield production of fusion proteins.

• 한국수소및신에너지학회논문집
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• 제33권6호
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• pp.636-642
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• 2022

The "Hydrogen Economic Activation Road map" was announced in 2019, and hydrogen demand is expected to exceed 470,000 tons per year in 2022 and keep increasing. Under this circumstance, it has become important to understand the greenhouse gas (GHG) emissions associated with various hydrogen production pathways. In this study, the evaluation of life cycle GHG emissions regarding the hydrogen produced as by-product from coke oven gas (COG) in steel mill is conducted. To cover the possible range of operations, three literatures were reviewed and their data of inputs and outputs for the process were adopted for calculation. Life cycle inventories and emission factors were mostly referred to GaBi and Intergovernmental Panel on Climate Change (IPCC) guidelines, respectively. When there are multiple products from a single process, the energy allocation method was applied. Based on these sources and the assumptions, the life cycle emission values of COG-based hydrogen were found to be 3.8 to 4.7 kg/CO₂-eq./kg-H₂.

• 한국물환경학회지
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• 제38권6호
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• pp.267-274
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• 2022

This paper is a result of research conducted on the 800,000 m³/d capacity of A Water Treatment Plant (WTP) and 400,000 m³/d capacity of B WTP plant in operation in the Nakdong River region. We evaluated the effect of algae broom on the WTP operation based on the running data of both WTP and the data on the pre-oxidation process field test for algae control using sodium permanganate (SPM) at the B WTP. The study results showed that during the algal bloom period, the coagulant dose increased by 102% in A WTP and 58% in B WTP, respectively, and the chlorine dose also increased by 38% and 29%, respectively, which may affect Total trihalomethane (THM) production. Data such as algal populations and Chl-a, residual chlorine and THM, algal populations, and ozone dose appeared also highly correlated, confirming that algal broom affects WTP operations, including water quality and chemical dosage. As a result of the field test of B WTP, THMs appeared lower than that of the control, suggesting the possibility of the SPM pre-oxidation process as an alternative to algae-related water quality management. Furthermore, in terms of GHG emissions due to energy consumption, it was observed that the pre-oxidation process using SPM was approximately 10.8%, which is a very low ratio compared to the pre-ozonation process. Therefore, these results suggest that the SPM pre-oxidation process can be recommended as an alternative to low-carbon water purification technology.

• Applied Biological Chemistry
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• 제30권2호
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• pp.169-178
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• 1987

Kluyveromyces marxianus로 부터 inulase를 생산하고 정제하며 intra 및 extracellular inulase의 성질을 조사하였다. 본 균주는 stationary phase인 24시간째 intra 및 extracelullar enzyme의 생산이 최고에 달했으며 유기 질소원으로 YNB를 사용하고 배양 중 pH를 조절해 줌으로써 효소 생산을 향상시킬 수 있었다. 조효소는 DEAE-cellulose에 의해 intra 및 extracellular inulase 모두 2개의 fraction으로 분리되었고 각 fraction의 전기영동 양상은 비슷하여 주 band를 비롯 모두 3개의 glycoprotein band가 관찰되었으며 이중 주 band만 inulase 및 invertase activity를 보유하고 있었다. 정제 효소의 inulase 및 invertase의 최적 pH는 각각 5.0과 4.5였고 intra가 extracellular enzyme 에 비해 다소 넓은 범위의 pH에서 높은 활성을 나타내었다. 모든 fraction의 최적 온도는 inulase가 $40^{\circ}C$, invertase가 $50^{\circ}C$였으며 intracellular enzyme이 더 넓은 범위의 온도에서 안정하였고 열에 대한 안정성도 intracellular inulase가 extracellular inulase보다 높게 나타났다. Km value는 intra가 $16{\sim}19mM$, extracellular inulase가 $9{\sim}11mM$로써 extracellular inulase가 inulin에 대한 친화력이 더 높았으나 모두 exo-type의 inulase로 판명되었다.

• 한국미생물·생명공학회지
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• 제37권2호
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• pp.105-109
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• 2009

단백질 인산화를 통한 세포내 신호전달기구 중 serine/threonine kinase에 속하는 Akt/PKB는 세포 생존과 사멸, 당대사 등을 조절하는 것으로 알려져 있다. 이러한 이유로, Akt/PKB 단백질은 천연물질들로부터 항암제를 탐색하기 위한 한 가지 target으로 사용되어 왔다. 본 연구에서는 Akt/PKB 단백질을 대량으로 생산하기 위하여 대장균의 단백질 발현 시스템을 이용하여 human Akt/PKB 단백질을 발현시켰다. 대장균에서 대량 발현된 Akt는 일반적인 조건에서는 inclusion body를 형성하였다. 배양온도 $27^{\circ}C$에서 0.01-0.09 mM IPTG로 발현 유도 시 발현된 human Akt/PKB 단백질 상당 부분이 가용화 되었다. 발현된 Akt kinase를 $Ni^{2+}$-NTA agarose column으로 정제하고, anti-Akt antibody를 이용하여 정제된 단백질이 Akt kinase 임을 확인하였다. 정제된 human Akt/PKB 단백질은 세포추출물에 존재하는 인산화 단백질을 이용하여 in vitro에서 인산화 되었으며, 인산화된 활성형 human Akt/PKB protein kinase는 human Akt/PKB protein kinase 특이 형광 peptide를 특이적으로 인산화하였다.

• 한국미생물·생명공학회지
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• 제46권3호
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• pp.244-252
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• 2018

Protein disulfide isomerase A3 (PDIA3) is a major member of the protein disulfide isomerase (PDI) family. PDI proteins commonly reside in the endoplasmic reticulum and mediate important thiol-disulfide interchanges during post-translational protein folding. Unlike other PDI family members, PDIA3 is ubiquitous in various organ systems. However, its physiological activity varies in other tissues. PDIA3 has been associated with cancer, airway inflammation, neurodegenerative diseases, and metabolic diseases. However, the mechanisms of the association of PDIA3 with these pathological conditions remain unclear. Recombinant PDIA3 (rPDIA3) is needed to clarify the interactions between PDIA3 and certain physiological phenomena. In the present study, we aimed to produce highly purified rPDIA3 for use in pathological experiments. We expressed rPDIA3 with a histidine-enriched elongated peptide tag in Escherichia coli and obtained rPDIA3 at 97.8% purity using consecutive His-tag and reverse-phase chromatography. Elongated peptide tags screened from artificially designated library had dual functions for protein expression and simple purification.