• Biotechnology and Bioprocess Engineering:BBE
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• 제2권2호
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• pp.82-85
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• 1997

The nar promoter as an inducible promoter was characterized for the process development for the gene expression and the protein production under anaerobic condition. The LB medium was selected as a main culture medium showing the enzyme activity of 18,000 units/min/g cell in the flask cultivation. The optimum concentration of nitrate was 1%. Under anaerobic conditions, the gene expression was fully induced in the presence of nitrate.

• 한국지하수토양환경학회지:지하수토양환경
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• 제15권6호
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• pp.114-121
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• 2010

Oxygen sensitivity and substrate requirement have been known as possible reasons for the intricate growth of Dehalococcoides spp. and limiting factors of for routinely applying bioaugmentation using anaerobic Dehalococcoides-containing microbes for remediating chlorinated organic compounds. To explore the effect of the short-term exposure of the short-term exposure of oxygen on Dehalococcoides capability, dechlorination performance, and hydrogen production fermentation from formate, an anaerobic reductive dechlorination mixed-culture (Evanite culture) including dehalococcoides spp. was in this study. In the results, once the mixed-culture were exposed to oxygen, trichloroethylene (TCE) degradation rate decreased and it was not fully recovered even addition of excess formate for 40 days. In contrast, hydrogen was continuously produced by hydrogen-fermentation process even under oxygen presence. The results indicate that although the oxygen-exposed cells cannot completely dechlorinate TCE to ethylene (ETH), hydrogen fermentation process was not affected by oxygen presence. These results suggest that dechlorinating microbes may more sensitive to oxygen than fermenting microbes, and monitoring dechlorinators activity may be critical to achieve an successful remediation of a TCE contaminated-aquifer through bioaugmentation using Dehalococcoides spp..

• 미생물학회지
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• 제18권3호
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• pp.148-152
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• 1980

The microwave of 2450 MHz, generated by a household cooking oven, was evaluated for its applicability to melt various rehydrated media and to remove dissolved oxygen from tubed media for anaerobic culture. The effect on the sterilization of E. coli in selective media was also evaluated. The following results were obtained. 10 The microwave oven was useful in saving time for melting media and in eliminating heat and combustion gas from the laboratory, which were inevitable by-products in the conventional flame method. 2) Dissolved oxygen could be removed without boiling over by exposing the tubes of anaerobic culture medium after putting them in a wire basket in a beaker with water. 30 The count of E. coli during the melting of MacConkey and EMB agar were similar to those treated with open flame. The microwave treatment was not considered a possible mean to replace autoclaving even in these selective media.

• 한국지하수토양환경학회지:지하수토양환경
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• 제17권5호
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• pp.49-55
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• 2012

A 1.28 L-batch reactor and continuous-flow stirred tank reactor (CFSTR) fed with formate and trichloroethene (TCE) were operated for 120 days and 56 days, respectively, to study the effect of formate as electron donor on anaerobic reductive dechlorination (ARD) of TCE to cis-1,2-dichloroethylene (c-DCE), vinyl chloride (VC), and ethylene (ETH). In batch reactor, injected 60 ${\mu}mol$ TCE was completely degraded in the presence of 20% hydrogen gas ($H_2$) in less than 8 days by anaerobic dechlorination mixed-culture (300 mg-soluble protein), Evanite Culture with ability to completely degrade tetrachloroethene (PCE) and -TCE to ETH under anaerobic conditions. Once the formate was used as electron donor instead of hydrogen gas in batch or chemostat system, the TCE-dechlorination rate decreased and acetate production rate increased. It indicates that the concentration of hydrogen produced in both systems is possibly more close to threshold for homoacetogenesis process. Soluble protein concentration of Evanite culture during the batch test increased from 300 mg to 688 mg for 120 days. Through the protein monitoring, we confirmed an increase of microbial population during the reactor operation. In CFSTR test, TCE was fed continuously at 9.9 ppm (75.38 ${\mu}mol/L$) and the influent formate feed concentration increased stepwise from 1.3 mmol/L to 14.3 mmol/L. Injected TCE was accumulated at 18 days of HRT, but TCE was completely degraded at 36 days of HRT without accumulation of the injected-TCE during the left of experiment period, getting $H_2$ from fermentative hydrogen production of injected formate. Although c-DCE was also accumulated for 23 days after beginning of CFSTR operation, it reached steady-state in the presence of excessive formate. We also evaluated microbial dynamic of the culture at different chemical state in the reactor by DGGE (denaturing gradient gel electrophoresis).

• 문화기술의 융합
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• 제4권2호
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• pp.179-183
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• 2018

요즘 음식물쓰레기를 혐기성소화조에서 바이오가스와 유기성 퇴비를 생산하고자 하는 연구가 늘어나고 있다. 본 연구에서는 음식물쓰레기를 미생물제재로 발효시켜 바이오가스와 퇴비를 생산하기 위한 기초실험을 행하였다. 먼저, 각종 미생물을 조합하여 미생물재제를 개발하고, 이를 음식물쓰레기 Batch실험에서 발생하는 바이오가스 발생량을 확인하였다. 또한 실증플랜트에서 바이오가스 발생량과 퇴비화를 통해 혐기성소화조 바이오가스 생산 극대화와 실증화를 확인하였다.

• 문화기술의 융합
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• 제5권1호
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• pp.327-332
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• 2019

본 연구는 여자 농구선수들을 대상으로 4주간의 엽산과 비타민 $B_{12}$ 섭취가 혈액학적 요인 및 면역인자, 유 무산소성 운동능력에 미치는 효과를 알아보는데 목적이 있다. 연구대상자를 섭취군과 통제군 각각 9명으로 선정하였으며, 4주간의 엽산과 비타민 $B_{12}$ 섭취 전 후 결과를 관찰하여 다음과 같은 결과를 도출하였다. 유 무산소 능력 측정 결과 섭취군에서 유의한 효과가 나타났으며, 혈액요인 분석의 경우 RBC, Hct의 섭취군에서 유의한 효과가 나타났다. 한편, 염증 및 면역 분석 결과 섭취군에서 평균적으로 유의하게 증가하는 경향을 보였으나 통계적으로 섭취군과 통제군 모두 유의한 효과가 나타나지 않았다. 결론적으로, 위와 같은 연구의 결과를 미루어볼 때, 여성 농구선수의 유 무산소성 운동 능력 향상을 위한 엽산과 비타민 $B_{12}$ 섭취는 경기력 향상을 기대할 수 있다.

• 한국수소및신에너지학회논문집
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• 제13권4호
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• pp.321-329
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• 2002

Clostridium butyricum, Lactobacillus amylophillus, Lactobacillus amylovorus, Lactobacillus acidophillus, AI-9 produced hydrogen and /or organic acids using glucose, lactose and starch at the anaerobic culture conditions. Cl. butyricum NCIB 9576 evolved 1,700 ml H2/L-culture broth and accumulated butyric acid, acetic acid, propionic acid and ethanol in its culture broth when lactose was used as a carbon source during 24 hrs of fermentation. L. amylovorus ATCC 33620 accumulated lactic and acetic acids and some reducing sugars when starch was used as a carbon source without hydrogen production. Instead of starch as a carbon source, L. amylovorus ATCC 33620 produced lactic acid from algal biomass during fermentation and the acid-heat or freeze-thaw pretreatment of algal biomass accelerate the lactic acid fermentation.

• 상하수도학회지
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• 제8권1호
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• pp.27-33
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• 1994

With the rapid industrialization, an ever-increasing quantity and kind of new organic compounds pose environmental problems due to their toxicity and physiological effect. However, research on the biodegradation of these compounds under anaerobic condition is very limited inspite of its efficiency and economical advantage. In this research, the pH effect on the ring cleavage of phenol under anaerobic condition was investigated, and the theory of phase separation was applied to the degradation of phenol for investigating the role of acidogenic bacteria. Results, obtained from biochemical methane potential(BMP) assay for 15.5 days of incubation, showed that acidic condition was more desirable for phenol degradation than alkaline condition. By both unacclimated methanogenic granular sludge and two mixed cultures, phenol was completely removed within six weeks of incubation with a gas conversion rate of over 86% of theoretical one. However, phenol was not degraded by unacclimated acidogenic culture, and thus it is considered as a syntrophic substrate. In case of phase separated biochemical methane potential(PSBMP) assay, in which acidogenic and methanogenic culture were seeded separately and consecutively, those that had been subjected to normal acidogens for 3 to 4 weeks showed higher gas production than those seeded with sterile or frozen culture.

• 미생물학회지
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• 제23권1호
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• pp.43-48
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• 1985

철저한 혐기적 방법으로 배양분리한 결과 편성 혐기성세균의 분리율이 높아졌고, 검체당 평균 3.3주가 분리되었다. 혈액배지인 NATB배지와 BA배지에서 비혈액배지인 NAT배지와 GAM배지에서 보다 세균 분리효과가 우수했다. NATB배지에는 혐기성 그람 양성 구균에 좋은 분리효과를 나타내었고, 그람 음성 간균은 15주 분리되었다. 이 중 Bacteroides가 12주로서 가장 많이 존재하는 균종이었다.

• 한국미생물·생명공학회지
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• 제20권4호
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• pp.430-436
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• 1992

수소 생성능이 있는 Clostridium butyricum과 이 균주의 대사산물을 이용하여 수소를 생성할 수 있는 광합성 세균의 혼합 배양에 의하여 수소 생성을 할 수 있는 양 균주의 혼합 배양 동력학적 연구를 수행하였다. 혐기성 Clostridia의 발효에서 생성되는 아세트산염과 부티르산염은 Rhodopseudomonas sphaeroides에 의해 이용되어 수소를 생성하게 되었고, 이들 양 균주를 혼합 배양한 결과 수소 생성을 저해하는 아세트산염과 부티르산염의 배지내 농도는 점차 감소하였다. 이들 두 균주의 혼합 배양에서의 균체의 혼합 비율, 혼합시기, 접종량을 조사함으로써 단독 배양시와 비교하면서 최적 조건을 조사하였고, 혼합시 균체량의 비율 Clostridium 속 세균1부에 대하여 Rhodopseudomonas 속 세균 6부의 비율로 혼합할 수 있음을 확인하였다.