• 미생물학회지
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• 제28권4호
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• pp.311-317
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• 1990

Intraspecific and interspecific protoplast fusions in/between C. thermocellum and C. thermohydrosulfuricum were studied. Protoplast fusions were well induced in 30-40% PEG solution, however, their fusion frequencies were low level of 1.2*10$^{-7}$ for intraspecific fusion of C. thermocellum, $6.7*10^{-7}$ for C. thermohydrosulfuricum, and 4.2*10$^{-7}$ for interspecific fusion between above two Clostridia, respectively. Most fusants were unstable and segregated after 3 subcultures. Relatively stable intraspecific C. thermocellum fusant FTT17, intraspecific C. thermohydrosulfurecum fusant FSS22 and interspecific fusant FTS3, which were stable after several subcultures, were selected and properties of fusants were further investigated, Phenotypes of the fusants were similar with wild types mostly in cellular morphology, carbon source assimilation and enzyme activities. However they were differed in assimilation of pyruvic acid and sorbitol as carbon source. The DNA contents of fusants were slightly increased compared with wild types. Ethanol production by intraspecific and/or interspecific fusants was not increased, however, acetic acid production as byproduct was decreased or not detected, which indicates that industrial thermophilic anaerobes can be improved by means of protoplast fusion of two strains.

• 신재생에너지
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• 제4권2호
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• pp.21-30
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• 2008

Anaerobic digestion (AD) is the most promising method of treating and recycling of different organic wastes, such as OFMSW, household wastes, animal manure, agro-industrial wastes, industrial organic wastes and sewage sludge. During AD, i.e. degradation in the absence of oxygen, organic material is decomposed by anaerobes forming degestates such as an excellent fertilizer and biogas, a mixture of carbon dioxide and methane. AD has been one of the leading technologies that can make a large contribution to producing renewable energy and to reducing $CO_2$ and other GHG emission, it is becoming a key method for both waste treatment and recovery of a renewable fuel and other valuable co-products. A classification of the basic AD technologies for the production of biogas can be made according to the dry matter of biowaste and digestion temperature, which divide the AD process in wet and dry, mesophilic and thermophilic. The biogas produced from AD plant can be utilized as an alternative energy source, for lighting and cooking in case of small-scale, for CHP and vehicle fuel or fuel in industrials in case of large-scale. This paper provides an overview of the status of biogas production and utilization technologies.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2008년도 춘계학술대회 논문집
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• pp.202-205
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• 2008

Anaerobic digestion(AD) is the most promising method of treating and recycling of different organic wastes, such as OFMSW, household wastes, animal manure, agro-industrial wastes, industrial organic wastes and sewage sludge. During AD, i.e. degradation in the absence of oxygen, organic material is decomposed by anaerobes forming degestates such as an excellent fertilizer and biogas, a mixture of carbon dioxide and methane. AD has been one of the leading technologies that can make a large contribution to producing renewable energy and to reducing $CO_2$ and other GHG emission, it is becoming a key method for both waste treatment and recovery of a renewable fuel and other valuable co-products. A classification of the basic AD technologies for the production of biogas can be made according to the dry matter of biowaste and digestion temperature, which divide the AD process in wet and dry, mesophilic and thermophilic. The biogas produced from AD plant can be utilized as an alternative energy source, for lighting and cooking in case of small-scale, for CHP and vehicle fuel or fuel in industrials in case of large-scale. This paper provides an overview of the status of biogas production and utilization technologies.

• Journal of Microbiology and Biotechnology
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• 제33권12호
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• pp.1681-1691
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• 2023

Flavin mononucleotide-binding proteins or domains emit cyan-green fluorescence under aerobic and anaerobic conditions, but relatively low fluorescence and less thermostability limit their application as reporters. In this work, we incorporated the codon-optimized fluorescent protein from Chlamydomonas reinhardtii with two different linkers independently into the redox-responsive split intein construct, overexpressed the precursors in hyperoxic Escherichia coli SHuffle T7 strain, and cyclized the target proteins in vitro in the presence of the reducing agent. Compared with the purified linear protein, the cyclic protein with the short linker displayed enhanced fluorescence. In contrast, cyclized protein with incorporation of the long linker including the myc-tag and human rhinovirus 3C protease cleavable sequence emitted slightly increased fluorescence compared with the protein linearized with the protease cleavage. The cyclic protein with the short linker also exhibited increased thermal stability and exopeptidase resistance. Moreover, induction of the target proteins in an oxygen-deficient culture rendered fluorescent E. coli BL21 (DE3) cells brighter than those overexpressing the linear construct. Thus, the cyclic reporter can hopefully be used in certain thermophilic anaerobes.

• 한국미생물·생명공학회지
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• 제8권3호
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• pp.155-166
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• 1980

어육 연제품의 부패에 관여하는 세균의 보급원이 되고있는 부원료의 미생물 오염 실태를 알기 위하여 어육 소시지 가공공장과 시중에서 채취한 녹말, 각종 향신료 및 조미료 20종에 총 시료수 59점에 대하에 생균수, 대장균군, 분변계대장균, 곰팡이 및 효모, 내열균, 호기성 아포형성균(중온 및 고온균), 혐기성 아포형성균(중온 및 고온균), 혐기성 황화수소변패 아포형성균을 조사하였다. 1. 부원료 중 녹말, 후추, 고추가루, 양파, 마늘, 생강, 육즙, 프랑크 등은 일반세균 및 포자형성균의 오염이 높았으며 시판품이 가공공장의 것보다 세균함량이 많았다. 2. 생균수가 높았던 시료는 내열균, 호기성 아포형성 중온균 및 고온균의 함량이 높았다. 3. 가공공장의 후추와 육즙, 시판품의 후추, 고추가루, 양파, 마늘 등은 외국의 세균관계기준을 초과하고 있다. 4. 생균수는 가공공장의 후추, 밀가루, 양파, 마늘이 $10^4$~$10^{5}$ /g이었고 시판의 후추, 고춧가루, 양파, 마늘이 $10^{5}$ ~$10^{7}$ /g이였으며 후추정유와 색소에서는 검출되지 않았다. 5. 대장균군이 검출된 시료는 생균수의 함량이 높았던 종류들이며 후추, 고추가루를 제외한 다른 시료에서는 분변계대장균이 검출되지 아니하였다. 6. 곰팡이 및 효모는 가공공장의 녹말, 밀가루, 후추가 140~460/g이었고 시판하는 후추와 고추가루는 $10^3$/g이였으며, 다른 시료에서는 검출되지 아니 하였다. 7. 10$0^{\circ}C$에서 5분간 끓인 후 55$^{\circ}C$에서 배양한 혐기성 황화수소변패 아포형성균은 본 실험에 제공된 어느 시료에서도 검출되지 않았다.

• 실내환경 및 냄새 학회지
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• 제16권2호
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• pp.187-198
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• 2017

It is very important to treat infected livestock carcasses safely and quickly. In this study, the degradation characteristics and odor generation characteristics of carcasses were investigated during the treatment of swine carcasses using the anaerobic burial composting method. While the carcasses were decomposed, the temperature remained high, at $40{\sim}55^{\circ}C$ on average, and most of the carcasses were decomposed rapidly. The major odor-contributing substances in the buried composting method are sulfuric odor substances such as $H_2S$, $CH_3SH$, dimethyl sulfide (DMS) and dimethyl disulfide (DMDS), and the odor contribution of these substances is 93~99%. Among them, $CH_3SH$, which accounts for about 56~89% of odor contribution, was the most representative indicator substance. Despite the anaerobic digestion process, the methane concentration in the digestion process was as low as 0.5~0.8% at the burial point of the carcass. The odor and methane produced during the decomposition of the carcasses decreased considerably during the discharge to the surface layer through the buried layer consisting of compost. These results suggest that anaerobic high temperature burial composting is one of the most useful methods to treat carcasses of infected livestock.