• 한국미생물·생명공학회지
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• 제13권1호
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• pp.93-101
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• 1985

Much of the progress in genetic engineering has been accomplished by employing Escherichia coli as the host organism. For many reasons, however, some other organisms have greater potential as alternatives to E. coli. In particular, streptomycetes are attractive organisms as hosts especially for the producation of various secondary metabolites such as antibiotics. In this article, therefore, we reviewed the techniques for development of vector system and expression of genes for antibiotic biosynthesis in streptomycete hosts.

• 수산해양교육연구
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• 제20권1호
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• pp.23-35
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• 2008

The purposes of this study are to analyze problems in industrial classification of fisheries in Korea and to suggest future directions. Based on a thorough review of relevant literature, the study proposes a five-level scheme for classifying fisheries. The highest level should be the fisheries industry, and the next highest level ought to be fisheries. The medium level should include fishing, aquaculture, and fishery service industries. At the fourth level, fishing is to be further divided into sea fishery and inland fishery, aquaculture into sea-surface aquaculture and inland aquaculture, and fishery service industries into integrated fishery service and fishery distribution service. The lowest level is the most detailed. At this level, sea fishery is split into deep sea fishery, offshore fishery, and coastal fishery; sea-surface aquaculture consists of sea aquaculture, seed production aquaculture, and food organism aquaculture; integrated fishery service is further classified into fishery-related service and fishery information service.

• Biotechnology and Bioprocess Engineering:BBE
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• 제10권6호
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• pp.587-592
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• 2005

Hydrolyzates from lignocellulosic biomass contain a mixture of simple sugars; the predominant ones being glucose, cellobiose and xylose. The fermentation of such mixtures to ethanol or other chemicals requires an understanding of how each of these substrates is utilized. Candida lusitaniae can efficiently produce ethanol from both glucose and cellobiose and is an attractive organism for ethanol production. Experiments were performed to obtain kinetic data for ethanol production from glucose, cellobiose and xylose. Various combinations were tested in order to determine kinetic behavior with multiple carbon sources. Glucose was shown to repress the utilization of cellobiose and xylose. However, cellobiose and xylose were simultaneously utilized after glucose depletion. Maximum volumetric ethanol production rates were 0.56, 0.33, and 0.003 g/L h from glucose, cellobiose and xylose, respectively. A kinetic model based on cAMP mediated catabolite repression was developed. This model adequately described the growth and ethanol production from a mixture of sugars in a batch culture.

• International Journal of Oral Biology
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• 제41권1호
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• pp.39-43
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• 2016

Dental caries, the most common oral disease, is a multifactorial disease caused by interactions among bacteria within the dental plaque, food, and saliva, resulting in tooth destruction. Streptococcus mutans has been strongly implicated as the causative organism in dental caries and is frequently isolated from human dental plaque. Photodynamic therapy (PDT) is a technique that involves the activation of photosensitizer by light in the presence of tissue oxygen, resulting in the production of reactive radicals capable of inducing cell death. Postantibiotic effect (PAE) is defined as the duration of suppressed bacterial growth following brief exposure to an antibiotic. In this study, the in vitro PAE of PDT using erythrosine and light emitting diode on S. mutans ATCC 25175 was investigated. The PAE of PDT for 1 s irradiation and 3 s irradiation were 1.65 h and 2.1 h, respectively. The present study thus confirmed PAE of PDT using erythrosine on S. mutans.

• 한국미생물학회:학술대회논문집
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• 한국미생물학회 2000년도 추계학술발표대회
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• pp.85-91
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• 2000

Aspergillus oryzae is a filamentous fungus classified in the group Aspergillaceae Ascomycetes. It is an important microorganism for industrial production of enzymes and fermented food productions. It secrets large quantities of proteins or enzymes into the culture medium which makes this organism appealing for the production of heterologous proteins. Recently Electric field-mediated transformation method, electroporation, has been applied to fungal transformation. In this study, fungal transformation was carried out by bypassing the protoplast isolation step, decreasing the culturing time and non-protoplast transformation for the increment of transformation efficiency. Transformants were obtained with electroporation in optimal condition 2,500 voltage, 1,540 ohm and 0.50 capacitance. More than 1,000 transform ants were obtained with 6-10 hrs cultured mycelia without enzyme treatment, called non-protoplast transformation.

• 미생물학회지
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• 제48권4호
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• pp.229-239
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• 2012

Cronobacter spp. (formerly Enterobacter sakazakii), a Gram-negative bacillus, is a rare cause of meningitis and central nervous system infections. In England, the first case infected by this organism occurred in 1958. By July 2008, approximately 120 documented cases of Cronobacter spp. infection and at least 27 deaths have been identified from all around the world in the published literature and in reports submitted by public health sectors. In 2007, it was proposed by European organizations that the original taxonomy of E. sakazakii would be revised, to consist of five new species moved to a new genus, and identified as "Cronobacter". E. sakazakii has thus now been reclassified as 6 separate species in the new genus, Cronobacter, gen. nov., within the Enterobacteriaceae family. The new species are presently Cronobacter sakazakii, C. turicensis, C. malonaticus, C. muytjensii, and C. dublinensis; the sixth species is identified simply as genomospecies I, as currently including only two representative strains. The objectives of this review are to provide insight on (1) the classification and taxonomy of Cronobacter spp., (2) its clinical etiology and pathogenicity, (3) prequency of Cronobacter spp. in different categories of ready-to-eat food other than infant formula, (4) methods for detecting, isolating and typing Cronobacter spp., and (5) recent research trends for detecting Cronobacter spp.

• 한국프랜차이즈경영연구
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• 제11권1호
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• pp.7-17
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• 2020

Purpose - As the competition in the foodservice franchise industry and the market becomes fierce and the entry barrier is lowered, the foodservice franchisor and franchisees strive to increase their competitive advantage in the market. Therefore, the franchisor and franchisees use experience management strategies to enhance the positive experiences of customers visiting the stores. In this regard, this study examines the effects of customer-oriented activities (physical-, social-, health-, and service-oriented activities) on utilitarian and hedonic values, and loyalty using stimulus-organism-response (S-O-R) model and value-expectancy theory. Research design, data, methodology - The data were collected from panels of online survey company, who visited a foodservice franchisee within last month. The survey was conducted for about 15 days from March 7, 2019 to March 21, 2019, and about 3,500 e-mails and messages were distributed to ask for the survey. A total 412 responded and completed the questionnaires. Of the 412 completed questionaires, 12 were discarded due to missing and misinformation data and 400 were retained for further data analysis. Results --The results showed that social oriented activities, health oriented activities, and service oriented activities had positive effects on hedonic value, while physical oriented activities did not have a significant effect on hedonic value. Health oriented activities and service oriented activities had positive effects on utilitarian value, while physical oriented activities and social oriented activities had no significant effects on utilitarian value. Hedonic and utilitarian values also have a positive effect on loyalty. Conclusions - First, food service franchises should provide services and menus in consideration of the health of customers. When a customer visits the store, franchisee should provide more health-oriented food or materials and clean and comfortable conditions so as not to threaten the health of the customer. Second, the food service franchise must build a service-oriented system. Foodservice franchisor need to provide continuous service training not only to the franchisees, but also to the employees of the franchisees. Third, franchise should design a store where customers can form social exchanges through providing various information exchange to customers and making the store as a local community center.

• 생태와환경
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• 제40권3호
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• pp.379-386
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• 2007

계면활성제의 주된 원료이며 Estrogenic hormone으로 알려진 nonylphenol이 수중생태계 먹이망의 하등생물군 성장에 미치는 독성영향을 파악하고자, 배양중인 조류(Microcytis aeruginosa), 편모충(Diphylleia rotans), 소형 (Brachionus calyciflorus) 및 대형동물플랑크톤(Daphnia magna)에 다양한 농도로 제작된 NP을 처리하고 각 개체군의 성장 및 동물플랑크톤 B. calyciflorus, D. magna의 발생특성을 각각 조사하였다. 예비실험을 통하여, 투여농도는 개체군에 따라 조류(0.01, 0.05, 0.10, 1.00mg $L^{-1}$), Diphylleia rotans (0.5, 1, 2.5, 5, 10 ${\mu}g\;L^{-1}$), Brachionus calyciflorus (0.1, 0.5, 1, 2.5, 5 ${\mu}g\;L^{-1}$), Daphnia magna (0.5, 1, 5, 10, 50 ${\mu}g\;L^{-1}$) 등으로 $4{\sim}5$단계 농도를 처리하였으며, 독성효과는 각 개체군의 현존량 변화로 산정 하였으며 실험은 각각 3회씩 반복 실행하였다. 분석결과, 예상했던 것처럼 모든 개체군은 NP농도가 증가할수록 강한 성장 억제를 보였다. 조류실험에서는 0.05 mg $L^{-1}$, D. rotans와 B. calyciflorus는 공히 10 ${\mu}g\;L^{-1}$, 대형동물플랑크톤 D. magna는 5.0 ${\mu}g\;L^{-1}$부터 각각 유의한 성장억제를 보였다. Nonylphenol에 대한 각 개체군의 $EC_{50}$은 B. calyciflorus (2.49 ${\mu}g\;L^{-1}$) < D. rotans (3.49 ${\mu}g\;L^{-1}$) < D. magna (7.61 ${\mu}g\;L^{-1}$) < M. aeruginosa (47 ${\mu}g\;L^{-1}$) 의 순으로 나타나 NP에 대해 조류세포가 가장 강한 내성을 보인 반면 B. calyciflorus가 가장 약한 것으로 나타났다. 또한 동물플랑크톤의 발생에 있어서 B. calyciflorus는 NP농도$(0.1{\sim}1{\mu}g\;L^{-1})$, D. magna는 이보다 약간 높은 NP농도 $(0.5{\sim}5{\mu}g\;L^{-1})$에서 공히 내구란이 형성되지 않았다. 이상의 결과를 종합하여 볼 때, 조류섭식자인 편모충이나 동물플랑크톤은 모두 nonylphenol에 대하여 조류보다 내성이 극히 약하며 특히 발생계에 치명적인 영향을 받기 때문에 NP가 유입되는 수계에 있어서 섭식자 소멸로 인한 식물플랑크톤 대발생의 인자로 작용할 수 있음을 시사해 주고 있다.

• 한국식품과학회지
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• 제25권5호
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• pp.449-455
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• 1993

장염 패혈증균으로 알려진 Vibrio vulnificus는 비교적 최근에 알려진 호염성균으로 이 균이 잠복된 어패류를 생식하면 사람에게 패혈증을 일으키며 높은 사망률을 나타내고 있다. 또한 이 균은 주로 해양환경에 서식하며 수온이 높은 하절기에 발생되고 있다. 본 실험에서는 전남 해안지역에서 해수, 개펄, 수족관내의 어패류와 주방환경의 시료원에서 장염 패혈증균의 분리율과 해수와 개펄의 이화학적인 성상과 일반 미생물 수, Vibrio균 수, Coloform 세균수의 분포를 조사한 결과 다음과 같은 결과를 얻었다. 즉 조사된 총 314건의 시료원 중에서 37.9%의 Vibrio 균종의 분리율을 보였으며 V. vulnificus가 7.1%, V parahemolyticus가 9.6%, V. alginolyticus가 12.4%, V. sp.가 8.9%가 나타났다. 또한 V. vulnificus의 시료원별 분리율은 해수에서 33.3% 개펄에서 55.6%, 수족관내 어패류에서 1.7%, 주방환경에서 6.3%로서 개펄에서 가장 높은 분리율을 보였다. 각 지역별 V. vulnificus의 분리율은 대략3.6%에서 11.4%의 범위를 가지고 있었으며 무안, 해남에서 10% 이상의 높은 분리율을 보였다. 그러나 지역별의 분리율 차이는 크게 인정되지 않는 경향이었다. 어패류에 있어서 V. vulnificus의 분리율은 1.7%였으며 주방환경에서는 6.3%였다. 어종별에 따른 차이는 인정할 수가 없었고 행주와 도마에서 높은 분리율을 보였다. 전남 각 지역별의 해수의 이화학적 성상은 염도가 $13.3{\sim}24.8%$, pH는 $7.64{\sim}8.36$, COD는 $0.8{\sim}12.6ppm$, 총인은 $0.003{\sim}0.175ppm$, 총질소량이 $0.219{\sim}1.634ppm$의 범위를 가지고 있었다. 개펄의 이화학적 성상은 총 유기물량이 $2.12{\sim}8.26%$, COD량이 $0.539{\sim}1.562ppm$, 총인은 $0.012{\sim}0.203ppm$, 총질소량이 $0.244{\sim}1.738ppm$의 범위로 나타났다. 한편 해수의 총세균수는 $4.5{\times}10^3{\sim}3.5{\times}10^5\;CFU/ml$, Vibrio 균수는 $1.8{\times}10^2{\sim}4.6{\times}10^3\;CFU/ml$, Coliform 세균수는 $1.9{\times}10^1{\times}3.7{\times}10^2\;CFU/100ml$이었으며, 개펄의 총 세균수는 $4.8{\times}10^3{\sim}5.2{\times}10^5\;CFU/ml$, Vibrio 균수는 $1.9{\times}10^2{\sim}8.4{\times}10^4\;CFU/ml$, Coliform 세균수는 $7.2{\times}10^1{\sim}9.9{\times}10^2\;CFU/100ml$으로 나타났다.

• 한국식품위생안전성학회지
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• 제25권4호
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• pp.333-340
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• 2010

누룽지 제조시설에서 공중낙하균, 작업장 내 시설 및 환경, 제조 종사자, 제조기기 및 주변기구, 원재료, 제조공정별 미생물학적 위해도를 조사하였다. 오염도는 취급하는 재료의 종류와 처리공간의 용도에 따라 차이가 있었다. 원재료를 비롯한 설비와 기구들의 오염은 심각하지 않은 상태이지만 교차오염에 주의할 필요가 있다. 또한 사람의 간섭도가 높은 공정에서 상대적으로 높은 오염도를 나타나 개인위생관리가 중요하다. 누룽지의 제조 공정 중 굽기공정($120{\sim}170^{\circ}C$, 약 10여분)에 의해서 미생물을 억제시킬 수 있기 때문에 굽기공정을 표준화하고 이와 관련된 기구 및 시설에 대한 철저한 관리가 필요하다. 중소규모 식품제조시설에서 미생물학적 오염도 관리를 위해서는 위생시설의 확충도 중요하지만 종사자의 위생에 대한 인식수준을 향상시키는 것이 가장 중요할 것으로 생각된다.