• Journal of Microbiology and Biotechnology
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• 제18권6호
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• pp.1130-1135
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• 2008

The effect of pH on anaerobic hydrogen production was investigated under various pH conditions ranging from pH 3 to 10. When the modified Gompertz equation was applied to the statistical analysis of the experimental data, the hydrogen production potential and specific hydrogen production rate at pH 5 were 1,182 ml and 112.5 ml/g biomass-h, respectively. In this experiment, the maximum theoretical hydrogen conversion ratio was 22.56%. The Haldane equation model was used to find the optimum pH for hydrogen production and the maximum specific hydrogen production rate. The optimum pH predicted by this model is 5.5 and the maximum specific hydrogen production rate is 119.6 ml/g VSS-h. These data fit well with the experimented data($r^2=0.98$).

• Journal of Microbiology and Biotechnology
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• 제23권8호
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• pp.1140-1146
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• 2013

Bioelectrochemical systems (BESs) have been suggested as a new technology for wastewater treatment while accomplishing energy and chemical generation. This study describes the performance of BESs based on mixed culture that are capable of reducing carbon dioxide to acetate. The cathode potential was a critical factor that affected the performance of the BESs. The rate of acetate production increased as the electrode potential became more negative, from 0.38 mM $d^{-1}$ (-900 mV vs. Ag/AgCl) to 2.35 mM $d^{-1}$ (-1,100 mV), while the electron recovery efficiency of carbon dioxide reduction to acetate increased from 53.6% to 89.5%. The microbial population was dominated by relatives of Acetobacterium woodii when a methanogenic inhibitor was added to the BESs initially.

• 한국조리학회지
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• 제9권3호
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• pp.130-140
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• 2003

김치로부터 유산균과 효모를 분리하여 분리균주의 혼합 배양액을 이용하여 제빵 공정의 최적화에 관하여 연구하였다. 김치로부터 젖산박테리아(lactic acid bactria)를 분리하여 제빵 환경에서 생육 조건이 좋은 것으로 나타난 저온 숙성 김치의 젖산균은 Leuconostoc mesenteroides와 Lactobacillus brevis의 2종이 선별되었고, yeast는 Saccharomyces fermentati, Saccharomyces cerevisiae 2종이 선별되었다. 분리된 4종의 균주를 적절하게 혼합배양시 co-work system을 형성하여 발효촉진의 효과를 보여주었다.

• 한국식생활문화학회지
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• 제10권3호
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• pp.167-174
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• 1995

A hazard analysis which included watching operations, measuring temperatures of foods throughout preparation and display, and sampling and testing for microorganisms of total plate counts and coliform bacteria was conducted in various phases of product flow of Naeng-myeun (Cold noodles) and Pi-bim bab (mixed rice) prepared at Korean restaurants. Large numbers of total plate counts were counted from the cooked foods after handling and holding. Ingestion of these foods must be considered high risk. Critical control points identified were, pre-preparation, food handling after cooking, and holding on display in product flow of Nang-Meon and pre-preparation, preparation, and holding on display in product flow of Pi-bim bab. It need for effective quality control of Nang-Meon and Pi-bim bab that training program consist of surveillance, education of the staff, standard operation procedures, forbidding dangerous processes and control of critical points.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2003년도 추계학술발표회
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• pp.454-457
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• 2003

A new approach for groundwater treatment combines a permeable Fe(0) barrier to breakdown higher chlorinated solvents like PCE and TCE with a downgradient aerobic biological treatment system to biotransform less chlorinated solvents, such as DCE and vinyl chloride (VC). The expected bacterial performance downgradient of an Fe(0) barrier was evaluated through laboratory batch experiments with a toluene-degrading mixed culture that cometabolically transforms cis-1,2-DCE and VC. The amount of cis-1,2-DCE (initially at 2,000 ppb) and VC (initially at 2,000 ppb) transformed was controlled by the initial toluene (20,000 ppb) concentration. VC was removed much more effectively than Cis-1,2-DCE, and a higher toluene concentration in comparison to the co-substrate concentrations was needed for complete co-substrate removal. Overall, the coupling of an Fe(0) barrier and subsequent biodegradation appears feasible for remediation of complex mixtures of chlorinated solvents and petroleum hydrocarbons in groundwater

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2003년도 추계학술발표회
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• pp.326-329
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• 2003

When an electrokinetic process is applied to a HOC-contaminated soil, hybrid types combined with soil flushing, chemical oxidation, and bioremediation are generally used. Especially when the electrokinetic process is combined with bioremediation, the hybrid technology can solve several limits of bioremediation such as low microbial mobility, low soil temperature, and shortage of nutrients in subsurface circumstance. Because microbial surface is charged negatively, the microorganism moves from cathode to anode under electrical field. In this study, mixed culture mainly-consisted by Pseudomonas sp. was applied to remediate pentadecane-contaminated kaolinite with particle size less than 300${\mu}{\textrm}{m}$. This remediation system was named ‘electrokinetic bioaugmentation’ and consisted of model aquifer, electrode reservoirs, bioreactor, power supply, and pump. The mixed culture above 0.5 of optical density in bioreactor was supplied to two reservoirs and penetrated soil when the electric current was applied. To enhance the removal efficiency, the optimal medium composition, electric current, and voltage were investigated.

• 대한미생물학회지
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• 제16권1호
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• pp.65-70
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• 1981

A microculture technique for the mixed lymphocyte culture test(MLC) in the sheep is described. The optimal incubation periods for the MLC are varied from 4 to 6 days depending on the sources of lymphocytes. It is found that a 2.5:1 stimulator-responder cell ratio and the responder cell concentration of $1{\times}10^5$ cells/well produce the highest($^3H$)-thymidine incorporation. Moreover cryopreservation of bovine lymphocytes results in satisfactory and reproducible MLC reaction. It is also evident that the MLC reactions of the sheep are under the control of histocompatibility matching between the stimulator cells and the responder cells. Significance of the technique as a too! for study on cell mediated immunity in sheep system, either normal or squamous cell carcinoma-bearing, are discussed.

• 한국동물학회지
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• 제38권2호
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• pp.186-195
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• 1995

사람의 항 HLA 단일군 항체 생산의 선결 조건인 가장 효과적인 시험관내 면역 조건을 확립하기 위해, 사람의 혈중 임파구를 함원으로 하여 마우스의 대식세포, 흉선세포. 이들의 조건배지, 그리고 임파구 촉진인자 등을 포함한 14가지의 다양한 배양 조건에서 세포를 배양하였으며, 마우스의 비장세포와 사람의 혈중 임파구에서 각각 항체 생산을 유도하였다. 항체의 생성 여부는 면역효소법(I섬SA)으로 조사하였다. 마우스의 비장세포는 모든 조건에서 다량의 항체가 검출되었으며, 사람의 혈중 임파구 분화에는 마우스의 조건배지보다 PWM. LPS와 같은 임파구 촉진인자가 효과적임을 알 수 있었으며. 특히 allogenic MLC(Mixed Lymphocyte Culture)에 의해 임파구 분화유도에 유용한 물질이 생성됨을 알 수 있었다.

• Journal of Microbiology
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• 제35권3호
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• pp.193-199
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• 1997

From several industrial wastewaters, 14 bacterial strains which degrade benzene, toluene, o-xylene, m-xylene, or p-xylene (BTX) were obtained. These strains were characterized as to their species composition and the substrate range, kinetic parameters and the substrate interactions were investigated. Although BTX components have a similar chemical structure, isolated strains showed different substrate ranges and kinetic parameters. None of the strains could degrade all of BTX components and most of them showed an inhibition (Haldane) kinetics on BTX, BTX mixtures were removed under inhibitory substrate interactions with variation in the intensity of inhibition. For a complete degradation of BTX, a defined mixed culture containing three different types of patyways was constructed and all of the BTX components were simultaneously degraded with the totla removal rate of 225.69 mg/g biomass/h Judging from the results, the obtained mixed culture seems to be useful for the treatment of BTX-contaminated wastewater or groundwater as well as for the removal of BTX from the contaminated air stream.

• 한국식생활문화학회지
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• 제20권3호
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• pp.315-322
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• 2005

Kimchi noodle have a original taste and characteristics. This noodle was used for sour kimchi, kimchi taste powder, red bean fiber and emulsified oil etc. with RS(resistant starch) premix as blended wheat flour mixed to resistant starch. For manufacturing process of this kimchi mixed dry noodle, suitable kimchi of $pH3.70{\sim}3.80$ was required storage period during $4{\sim}5days$ at room temperature. At this point, the suitable treating amount of sour kimchi was about 20%(w/w) level. Manufacturing of kimchi noodle could be at the suitable manufacturing condition from use of kimchi taste powder and red bean fiber etc. Calori of this kimchi noodle was 308.17Kcal/100g as low level than wheat flour noodle as 355.82Kcal/100g, decreasing effect of calori was about 13.39%. This kimchi noodle had a characteristic sour and hot taste, that wasn't required the special seasoning and/or soup at this result.