• Korean Journal of Organic Agriculture
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• v.27 no.1
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• pp.65-76
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• 2019

Bacillus genus are found abundantly in various sites and their secondary metabolites were used as potential agents in agriculture, notably plant growth promoting and bio-control. The objective of this study was to develop the culture conditions of GH1-13 strain including higher cell growth, stable endospore-forming and enhancement of potential agents which are related with plant growth promoting and phytopathogen suppression. The optimal carbon and nitrogen sources were determined by glucose and soy bean flour, respectively, then resulted in $7.5{\times}10^9cells/mL$, $6.8{\times}10^9\;endospore\;cells/mL$ and sporulation yield of 90% after 30 h cultivation in 500 L submerged fermenter at $37^{\circ}C$, pH 7.0. Cells and cell-free supernatant of GH1-13 strains showed the potent antifungal activity against phytopathogenic fungi of Colletotrichum gloeosporioides. It was also confirmed that indole-3-acetic acid (IAA) production of GH1-13 strain was greatly increased by addition of 0.3% tryptophan.

• Journal of the Korean Society of Marine Environment & Safety
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• v.24 no.7
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• pp.907-915
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• 2018

With the increase of metal usage in various industries, metal pollution and ecological toxicity in the environmental system have become a significant concern. A geo-statistical index has been widely used to determine contamination level with normalization through a background value. In this study, geo-statistical indexes such as an enrichment factor, accumulation index, and potential ecological risk index were used to assess metal pollution in soil at locations associated with shipbuilding manufacturing industries. Metal contamination, especially of Cu and Pb, was observed in some samples located closer to manufacturing sites. Enrichment factor and accumulation (IGEO) values were indicative of concerning levels of soil contamination in specific samples, and the soil contamination could be induced by anthropogenic sources. In further study, after more detailed sampling for soil and potential pollution sources, high interpretation techniques such as Pb isotope analysis and X-ray analysis will be needed to investigate source identification.

• 한국생물공학회:학술대회논문집
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• 2002.04a
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• pp.301-304
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• 2002

Perfusion culture strategies for high density culture of plant cell suspensions to enhance the productivity of extracellular polysaccharides were investigated. Angelica gigas Nakai cell suspensions were used to produce the extracellular polysaccharide and perfusion parameters were optimized to maximize the production. When the medium exchange was started at the fifth day after inoculation, the maximum cell concentration (23.8 g dry cell weight per liter) was achieved.

• 한국생물공학회:학술대회논문집
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• 2001.11a
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• pp.671-674
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• 2001

Cyclodextrin glucanotransferase(CGTase) derived from recombinant Bacillus subtilis was partial purified and concentrated by ultrafiltration. The prepared CGTase were immobilized on various matrices by ionic interaction or covalent bond. CGTase covalently bound on CNBr-activated sepharose 4B were identified to be the highest immobilization activity among various immobilization methods. The optimum conditions for CGTase immobilization were determined; $30^{\circ}C$, 6Orpm, using O.2g CNBr-activated sepharose 4B in pH 6.0 phosphate buffer and 9hr immobilization.

• Journal of Food Hygiene and Safety
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• v.35 no.4
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• pp.382-390
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• 2020

This study was carried out to evaluate the antimicrobial effect of red ginseng (Panax ginseng C.A. Meyer) against several foodborne pathogens including Staphylococcus aureus, Escherichia coli, Candida albicans and Aspergillus niger. The antimicrobial effect was determined by agar diffusion method using red ginseng extract, crude saponin and non-water-soluble fractions. Red ginseng extract showed antimicrobial effect against S. aureus, but not C. albicans or A. niger. The extract showed anti-bacterial activity at concentration above 30% against S. aureus, which cause both food poisoning and atophic dermatitis. Crude saponin showed antibacterial activity above 7.5% against the bacterium. However, the ginsenosides purified from crude saponin showed no antimicrobial activities at 100-200 ㎍/mL. To investigate the mode of growth inhibition, red ginseng extract and crude saponin were added to 0.85% NaCl solution containing S. aureus and then incubated at 35℃ for 12 h. The results showed that viable cells were rapidly reduced in above 10% concentration of red ginseng extract and above 2% of crude saponin, respectively. However, the crude saponin and red ginseng extract did not inhibit the bacterial cells completely at those same concentrations. On the other hand, whereas all non-water-soluble fractions showed inhibition zones above 10 mm against S. aureus, they showed no inhibition effects against E. coli, C. albicans or A. niger. The methanol fraction-1 (MF-1) showed the highest antibacterial activity against S. aureus, and the MIC (minimal inhibitory concentration) was 0.625 mg/mL. These results suggest that red ginseng extract, crude saponin and non-water-soluble fractions show selective antibacterial activity against S. aureus, and non-water-soluble fractions might be used as natural antibacterial agents.

• Clean Technology
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• v.14 no.1
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• pp.7-13
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• 2008

RPSA (Rapid Pressure Swing Adsorption) is a cyclic process which can be used to separate gas mixtures by adsorption method. Oxygen which is separated from air is used to the medical oxygen generator and biological wastewater treatment process. RPSA uses only one adsorption bed, so it is very simple to operate compared to conventional PSA process. In this work experimental parameters were examined with RPSA setup and parameters for the oxygen separation from air were obtained.

• 한국생물공학회:학술대회논문집
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• 2000.11a
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• pp.237-240
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• 2000

Organic acids which were produced from biomass wastes streams by cell-recycle fermentation using Propionibacterium acidipropionici ATCC 4965 were extracted by Membrane Contactor using TOA/MIBK system. Maximum productivity was 3.32g organic acid/L/hr at the dilution rate of 0.2/hr in the results of continuous fermentation. The diluted organic acids in the fermenter were selectively separated by Membrane Contactor extraction using 30%(w/w) trioctylamine(TOA) dissolved in methylisobutylketone(MIBK). The flow rate of aqueous phase is 200ml/min and that of extraction phase is 100ml/min. The degree of Acetic acid and Propionic acid extraction from fermentation broth was reached 56.25%, 72.41% respectively.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2014.05a
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• pp.864-866
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• 2014

현대 사회는 모든 분야에서 다양한 분야들의 기술들이 융합되는 사회이다. 농업 분야 또한 다양한 기술들과의 융합으로 생산 관리와 생육관리 등에서도 변화가 요구되고 있다. 하지만 급속히 정보화가 추진되고 있는 다른 분야에 비해 농업분야는 생물을 다루는 분야이기 때문에 발전 속도가 늦다. 하지만 정보화는 어쩔 수 없는 당면 과제이기에 농업 종합 관리 시스템은 꼭 필요한 시스템이다. 현재의 농업 정보화 시스템은 농업관측정보시스템과 농산물 유통 종합정보 시스템 그리고 농축산물 생산 및 수급정보 분석 시스템 등으로 볼 수 있다. 하지만 이러한 시스템은 초기의 기대와는 달리 농업관측 모형이 현실을 제대로 반영하지 못하는 문제점 등이 있어 비효율적으로 운용되고 있다. 이에 본 연구에서는 식물의 다양한 생육과 생산 최적화를 위해 RFID 센서를 이용하여, 관리함으로서 적은 노동력과 시간의 소모를 줄이고 소비자가 작물에 대한 다양한 정보를 접할 수 있는 시스템을 연구한다.

• The Korean Journal of Pesticide Science
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• v.20 no.3
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• pp.203-210
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• 2016

Polychlorinated biphenyls (PCBs) are ubiquitous environmental contaminants, found in the many environments. PCBs exerts various toxicological effects, including endocrine-disrupting activity. Most researches with these toxicants performed with soil matrix with mixtures of congeners, namely Aroclor, while the biological activities have been tested with animals. However, studies with pure congeners are limited. In this study, 5 congeners were synthesized and their fates (bioaccumulation, degradation, kinetics) were studied in carrot-soil system. The soil half-lives of biphenyl, PCB-1, PCB-3, PCB-77, and PCB-126 were 20.2, 16.0, 11.6, 46.5, 198.0 days, respectively. In general, the longer half-lives were observed with the higher hydrophoicity of PCBs. Times, required for maxium accumulation of PCBs in carrot (Tmax) were 10-20 days for most congeners and the concentrations were 0.4-2.6 mg/kg. The concentrations of PCBs in carrot were kept as constant after Tmax, except PCB-126. The concentration ratio between carrot and soil after 90 days of treatment were 1.7, 8.1, 1.9, 1.8, and 5.9 for biphenyl, PCB-1, PCB-3, PCB-77, and PCB-126. Because of the increase of biomass, the total residual amount of PCBs in carrots however, increased till the end of experiment. The portions of PCB-126 in carrot were 1.1% of the soil residues at 90 days after planting.

• Membrane Journal
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• v.10 no.4
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• pp.198-204
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• 2000

Pervaporation membranes were fabricated by low temperature plasma treatment the concentrate butanol solution from fermentation process. Effects of power, reaction time, and monomer flow rate were examined to optimize the (W!FM)t value as 4.0389 x 109 J . min/kg. Various organic compounds were tested in plasma treatment. Contact angle and relative sorption ratio were examined in terms of membrane performance. With the increase of contact angle and relative sorption ratio separation factor was enhanced from 0.186 to 3.525. and butanol flux increased from 0.042 to 0.567 kglm2. hr. Hydrophobicity of the membrane increased the affinity with butanoL Heat of mixing for monomer with butanol was examined, but failed to find the trend, because plasma polymerization of monomer produced the new compounds much different from monomers.