• 생명과학회지
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• 제7권4호
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• pp.377-383
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• 1997

The acute toxicity effect of triorganotin of trioganotin on the growth of microalgae and shellfish was investigated through flask culture. The value of 120 hr-LC$_{50}$ that is the median lethal concentration of TBTO on the shellfish (R. philipinarum) was found to be 6 $\mu$g/L. The acute toxicity effect of TBTO on T. suecica was obviously shown even at the concentration of 0.5 $\mu$g/L, and the effect diminished as the initial cell density increased. The effect also diminished less in the experiment done under aeration than in that done under non-aeration. To design a chemostat system for the test of chronic toxicity, the culture of T. suecica was executed in photobioreactor. In batch culture, the profiles of chlorophyII a and D.C.W. showed the growth of T. suecica very well, and the maximum specific growth rate was estimated to be 0.54 d$^{-1}$. with this value, as a dilution rate in contimuous culture, pH was nicely maintained between 7 and 9 when air was supplied with 3% CO$_{2}$. From all results and the natural environment of clam, a novel chemostat system was invented. Through this system, we can observe each independent toxicity effect of TBTO and plankton and combined toxicity effect as well.

• Journal of applied mathematics & informatics
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• 제32권5_6호
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• pp.555-566
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• 2014

In this paper, we formulate two chemostat type models of phytoplankton and zooplankton population dynamics with instant nutrient recycling to study the role of viral infection on phytoplankton. The infection is transmitted only among phytoplankton population and it makes them more vulnerable to predation by zooplankton. It is observe that the chemostat system is very stable in the absence of viral infection but the presence of viral infection make the chemostat system sensitive with respect to the grazing rate of infected-phytoplankton by zooplankton. Further, if the grazing rate is less than certain threshold the system remain stable and exhibits Hopf-bifurcation after crossing it.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2000년도 추계학술발표대회 및 bio-venture fair
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• pp.346-349
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• 2000

In order to investigate the characteristics for RNA accumulation, continuous cultures of S. cerevisiae MTY62 under the carbon-limitation or carbon-phosphate-limitation were performed. In the carbon-limited chemostat, the highest RNA content of 144 mg-RNA/g-dry cell was observed at the dilution rate of $0.30\;hr^{-1}$. In the carbon and phosphate-limited chemostat, the culture condition with the dilution rate of $0.25\;hr^{-1}$ gave the maximal RNA content of 209 mg-RNA/g-dry cell. The accumulation rate of RNA $(mg-RNA/L\;{\cdot}\;hr)$ was decreased at higher dilution rate in the carbon and phosphate-limited chemostat.

• Journal of Microbiology and Biotechnology
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• 제27권5호
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• pp.939-942
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• 2017

The cellular composition and metabolic compounds of Leuconostoc mesenteroides ATCC 8293 were analyzed after cultivation in an anaerobic chemostat. The macromolecular composition was 24.4% polysaccharide, 29.7% protein, 7.9% lipid, 2.9% DNA, and 7.4% RNA. Its amino acid composition included large amounts of lysine, glutamic acid, alanine, and leucine. Elements were in the order of C > O > N > H > S. The metabolites in chemostat culture were lactic acid (73.34 mM), acetic acid (7.69 mM), and mannitol (9.93 mM). These data provide a first view of the cellular composition of L. mesenteroides for use in metabolic flux analysis.

• The Korean Journal of Ecology
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• 제20권3호
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• pp.169-173
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• 1997

The measurement of cell death constant in Anabaena flos-aquae was tested by the Live/Dead BacLight Viability kit(Molecular Probes Co., Seatle, WA). When the Live/Dead BacLight Viability kit was applied to Anabaena flos-aquae, the cells with intact cell membranes(live cells) stained fluorescent green, while the cell with damaged membranes(dead cells) stained fluorescent red and the background remained virtually nonfluorescent. The rations of live : dead cells in the cell suspension were controlled artifically and Live/Dead BacLight Viability kit was applied to them. The ratios of green:red fluorescent cells in the cell suspension were the same as those of live : dead cells controlled artifically. It was also approved by the fluorescence emission. The cell death constant was measured in the P-limited Anabaena flos-aquae chemostal culture in the N-fixing and $KNO_3-supplied$ conditions. The culture in N-fixing chemostat had a dead cell proportion of 1.2% at the growth rate of 0.7/day and increased to 2.6% at the growth rate of 0.3/day. The cell death constant of N-fixing culture was 0.008/day.There was a same trend in the $KNO_3-supplied$ chemostat culture. The proportion of dead cell was 1.6% of dead cell proportion at the growth rate of 0.7/day and increased to 4.3% at the growth rate of 0.3/day.

• 한국수산과학회지
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• 제15권3호
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• pp.179-184
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• 1982

Lartobacillus bulgricus를 glucose를 제한기질로 하는 합성배지에서 연속배양한 결과를 요약하면 다음과 같다. 1. 본 실험 model은 Monod의 chemostat 이론을 적용시킬 수 있다. 2. 본 실험 model에서의 최대 cell production rate는 $0.178 g/1{\cdot}hr$로서 회석율 $0.414hr^{-1}$ 일 때이다. 3. 연속배양 결과 saturation constant($K_s$)는 7.69g/l, 최대비증식속도$(V_{max})$는 $0.62hr^{-1}$ 이었다. 4. wash out 현상은 $0.51hr^{-1}$에서 일어났으며cell yield coefficient는 0.016g/l 이었다.

• 한국어업기술학회:학술대회논문집
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• 한국어업기술학회 1997년도 수산관련공동학술대회발표요지집
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• pp.268-269
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• 1997

• 한국미생물·생명공학회지
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• 제17권3호
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• pp.173-177
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• 1989

HeLa 세포주의 연속 배양시 세포수가 배지의 이동속도가 증가함에 따라 감소하는 현상을 나타냈으며, 최대 세포수를 유지할 때의 dilution rate은 0.012(1/h)로 wash-out인 0.050(1/h)보다 극히 낮으며, dilution rate이 0.030(1/h)일 때 2.0(mL of cells/L/h)의 최대 세포 생산속도를 보였다. 또한 낮은 배지 이동속도에서 세포수의 감소에 따른 maintenance term의 존재를 확인했다. 더불어 packed cell volume파 산소소비속도의 측정값이 실제 세포증식과 밀접한 관계가 있음이 입증되어 간접방법에 의한 생육도치 측정이 가능하게 되었다. 또한 산소 yield model에 의해 최대 산소 수율, $Y_{O2}^{max}$과 maintenance 산소소비속도, m$_{O2}$가 각각 4.1$\times$$10^5$(cells/mmole $O_2$)와 10.71$\times$$10^{-9}$(mmole $O_2$/ cells/h)로 측정되었다.

• 농업과학연구
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• 제11권2호
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• pp.322-327
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• 1984

전보(前報)에서 분리(分離)한 Rhizobium meliloti M14를 공시(供試)하여 그 종균생산(種菌生産)을 위한 기초적(基礎的) 연구(硏究)로서, 탄소원(炭素源) 및 질소원(窒素源), chemostat의 반련속식(半連續式) 운용(運用)에 의한 액체배양(液體培養)을 시도(試圖)하여 아래와 같은 결과(結果)를 얻었다. 1. 탄소원(炭素源) 비교(比較)한 단당류(單糖類), 이당류(二糖類) 및 당(糖)알콜류(類) 가운데 당(糖)알콜류(類)에서 가장 생육(生育)이 높았고 단당류중(單糖類中) 오탄당(五炭糖)에서의 생육(生育)은 육탄당(六炭糖)보다 저조(低調)하였다. 2. 천연(天然) 탄소원중(炭素源中) malt extract 및 molasses에서의 생육(生育)은 mannitol에서의 생육수준(生育水準) 이상(以上)이었다. 3. 질소원(窒素源)으로서 yeast water에 대(對)한 편향성(偏向性)이 인정(認定)되었으며 그 10%에서의 생육수준(生育水準)은 yeast extract 0.24%와 상응(相應)하였다. 4. Chemostat (MicroFerm 28L, New Brunswick model CMF-128S) 의 단식배양(單式培養)에 의(依)하여 36시간(時間) 배양(培養)으로 생균수(生菌數) $5{\sim}7{\times}10^9cells/ml$ 수준(水推)의 stationary phase에 도달(到達)하였고, 반련속식(半連續式) 운용(運用)으로 매(每) 24시간(時間)마다 동일수준(同一水準)의 생균(生菌)을 가진 배양액(培養液)을 그 운용량(運用量)에 대(對)하여 5분(分)의 4를 회수(回收)할 수 있었다.

• 한국환경생물학회:학술대회논문집
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• 한국환경생물학회 2005년도 추계학술대회 초록집
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• pp.94-94
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• 2005