• KSBB Journal
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• 제5권3호
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• pp.235-240
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• 1990

Pseudomonas elodea 에 의한 Gellan gum생산시 이에 관련된 기초자료를 얻기 위하여 회분식 및 연속식 발효를 하였다. 회분식 배양의 결과로부터 비성장 속도는 $0.16hr^-^1$이었으며 72시간 배양후의 점도는 4500cp, 생성물 농도 0.7g dry weught/100g broth, 및 생산성은 0.08g dry weight/1/hr이었다. 연속식 배양을 통하여 최적 탄소원과 질소원의 농도비(3.0mg-carbon/mg-nitrogen)를 결정하였으며 Gellan gum의 최대 생성속도는 희석율 $0.14hr^-^1$에서 0.6g dry weight/l/hr이었다. 이러한 조건에서 각종 metabolic paeameter값을 계산하였다. 또한 배양액의 유변학적 특성은 Casson equation에 잘 부합됨을 확인하였고, 배양액의 점도와 산소전달계수를 측정하여 고점도 배양시 산소전달의 장애현상을 조사하였다.

• 해양환경안전학회지
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• 제25권1호
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• pp.96-101
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• 2019

본 연구는 담녹조강 Tetraselmis suecica와 T. tetrathele의 인산염 흡수에 미치는 발광다이오드의 파장의 영향을 조사하였다. 파장은 청색 발광다이오드(LED; 450 nm), 황색 LED(590 nm), 적색 LED(630 nm) 그리고 형광램프(control)이며, 조도는 $100{\mu}mol\;m^{-2}\;s^{-1}$로 주사하였다. T. suecica와 T. tetrathele의 최대흡수속도(${\rho}_{max}$)는 적색 LED에서 $6.35pmol\;cell^{-1}\;hr^{-1}$와 $9.85pmol\;cell^{-1}\;hr^{-1}$로 나타났으며, 반포화농도(Ks)는 $9.43{\mu}M$와 $21.2{\mu}M$로 나타났다. 이는 적색 LED 아래에서 T. suecica와 T. tetrathele가 다른 파장보다 영양염에 대한 친화성이 높다는 것으로 의미한다. 따라서 경제성 및 생산성 향상을 위한 Tetraselmis 배양시스템(광배양기)의 최적 광원은 낮은 영양염 상태에서도 높은 생장속도를 보이는 적색 LED가 적합할 것으로 판단된다.

• Journal of Microbiology and Biotechnology
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• 제21권6호
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• pp.652-658
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• 2011

The growth kinetics of Streptomyces noursei NRRL 5126 was investigated under different aeration and agitation combinations in a 5.0 l stirred tank fermenter. Poly-${\varepsilon}$-lysine biosynthesis, cell mass formation, and glycerol utilization rates were affected markedly by both aeration and agitation. An agitation speed of 300 rpm and aeration rate at 2.0 vvm supported better yields of 1,622.81 mg/l with highest specific productivity of 15 mg/l.h. Fermentation kinetics performed under different aeration and agitation conditions showed poly- ${\varepsilon}$-lysine fermentation to be a growth-associated production. A constant DO at 40% in the growth phase and 20% in the production phase increased the poly-${\varepsilon}$-lysine yield as well as cell mass to their maximum values of 1,992.35 mg/l and 20.73 g/l, respectively. The oxygen transfer rate (OTR), oxygen utilization rate (OUR), and specific oxygen uptake rates ($qO_2$) in the fermentation broth increased in the growth phase and remained unchanged in the stationary phase.

• KSBB Journal
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• 제13권3호
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• pp.289-294
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• 1998

The effects of various step-fortifications of the initial medium with amino acids, glucose, and vitamines on the growth and metabolism of a hybridoma cell line in batch cultures were quantified. Comparisons between the metabolic rates of the various cultivations were made for the exponential growth phase. Fortification of the basal medium resulted in higher cell densities through a prolonged growth phase, but the maximum specific growth rate was not affected. The uptake rate of glutamine increased with the addition of amino acids but did not change upon the addition of glucose or vitamines. The specific glucose consumption decreased slightly with the addition of amino acids but increased production of lactate and {{{{ { NH}`_{4 } ^{ +} }}}}. A reciprocal relationship between the yields of {{{{ { NH}`_{4 } ^{+ } }}}} and lactate indicated a joint regulation of glycolysis and glutaminolysis.

• ALGAE
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• 제22권3호
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• pp.235-240
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• 2007

The red tide-causing flagellate Chattonella anticfua can cause mass fish kills by their clogging in fish gills. Thisstudy examined the nutrient requirements of C. antiqua isolated from Korea. C. anticfua displayed maximum growthat the day five, followed by a decrease in cell density. Nitrate and nitrite were the preferred nitrogen sources, alonewith adenosine diphosphate for phosphorus compounds. In medium that contained ammonium, a significantdecrease in cell density was observed. Half-saturation constants, Ks, calculated from the maximum growth ratewere 4.94 U|M for NC>3 and 0.79 flM for P04. The growth of C. antiqua was not within the function of the N:P ratio (RU= 0.29). With an N:P ratio as low as 10, the increase in cell density was apparent, with a higher division rate. At lev-els above 50 fiM of NaNOg or 8 ;uM of NaHUPCU, the growth rates were somewhat decreased. Phosphate was thelimiting factor for C. antiqua growth since the starvation of phosphate had brought about a rapid decrease in celldensity in semi-continuous culture. Studies about the temporal modification of the efficiency of nitrate or phosphateuptake may be necessary to explain the bloom dynamics of C. antiaua.

• Journal of Microbiology and Biotechnology
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• 제10권4호
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• pp.455-461
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• 2000

Abstract Spirulina platensis was grown in SWlUe waste to reduce inorganic compowlds and simultaneously produce feed resources. Spirulina platensis prefers nitrogenous compounds in Ibe order: $NH_4^{+}-N>NO_3^{-}-N>simple-N$ such as urea and simple amino acids. It even consumes $NH_4^{+}-N$ first when urea or nitrate are present. Therefore, the content of residual $NH_4^{+}-N$ in Spimlina platensis cultures can be determined by the relative extent of the following processes: (i) algal uptake and assimilation; (ii) ammonia stripping; and (iii) decomposition of urea to NH;-N by urease-positive bacteria. The removal rates of total nitrogen ffild total phosphorus were estimated as an indicator of the treatment effIciency. It was found that Spirulina platensis was able to reduce 70-93% of $P_4^{3-}-P$, 67-93% of inorganic nitrogen, 80-90% of COD, and 37-56% of organic nitrogen in various concentrations of swine waste over 12 days of batch cultivation. The removal of inorganic compounds from swine waste was mainly used for cell growth, however, the organic nitrogen removal was not related to cell growlb. A maximum cell density of 1.52 dry-g/l was maintained with a dilution rate of 0.2l/day in continuous cultivation by adding 30% swine waste. The nitrogen and phosphorus removal rates were correlated to the dilution rates. Based on the amino acid profile, the quality of the proteins in the Spirulina platensis grown in the waste was the same as that in a clean culture.ulture.

• Journal of Microbiology and Biotechnology
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• 제12권1호
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• pp.137-141
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• 2002

Anabaena variabilis ATCC 29413 grew in chromium (Cr) containing Chu-10 (basal) and nitrate-supplemented media, and the growth of the organism in $100{\mu}M$ chromium was found to be 50% of that in control medium. The growth in nitrate $({NO_3}^-)$ supplemented cultures was better as compared to cultures grown in basal medium. Free cells from basal and nitrate-supplemented media removed 5.2 and 7.4 nmol of chromium $mg^{-1}$protein in 8 h, respectively, from the medium containing $30{\mu}M$ chromium. The efficiency of chromium removal increased 7-fold in imidazole buffer (0.2 M, pH 7.0). A cell density equivalent to $100{\mu}g$ protein $ml^{-1}$ was found to be optimum for maximum Cr removal. Entrapment of cells in calcium-alginate beads did not affect the rate of Cr uptake by the cells. The efficiency of the laboratory-scale continuous flow bioreactor $(12.5{\times}2cm)$ loaded with alginate-immobilized cells (10 mg protein) and fed with $30{\mu}M$ chromium solution was compared at different flow rates. The efficiency of the bioreactor varied with flow rates. In terms of percent removal of Cr from influent, a flow rate of 0.1 ml $min^{-1}$ was found to be optimum for 6 h (54% Cr removal efficiency). Maximum amount of Cr (883 nmol) was removed by the cells in 3 h at a flow rate of 0.5 ml $min^{-1}$. The potential use of A. variabilis in removing Cr from industrial effluents is discussed.

• 한국습지학회지
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• 제14권1호
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• pp.121-130
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• 2012

본 연구에서는 2011년 6월부터 11월까지 충청남도 논산시 양지리의 가축폐수 처리를 위해 조성된 인공습지에서 정수식물인 갈대의 처리공정별 계절별 생물량 변이와 질소 인의 흡수량, 수처리 효율을 파악하기 위하여 수행되었다. 조사기간 동안 인공습지 내 갈대의 총 생물량은 200.1 ~ 669.4 kg의 범위로 보이며 계절별 총 생물량은 7월에 669.4 kg로 가장 높게 나타났다. 인공습지 내 갈대의 지상부 질소 함량은 $21.9{\pm}0.6{\sim}32.1{\pm}1.5mg/g$, 지하부는 $15.1{\pm}5.5{\sim}24.9{\pm}5.7mg/g$, 인의 함량은 지상부에서 $1.5{\pm}0.3{\sim}2.4{\pm}0.2mg/g$, 지하부는 $1.6{\pm}0.6{\sim}2.5{\pm}0.6mg/g$의 범위로 조사되었다. 인공습지 내 갈대의 질소 흡수량은 9.7 ~ 28.0 kg, 인의 흡수량은 0.7 ~ 2.8 kg의 범위로 조사되었다. 질소의 흡수량은 7월에 28.0 kg으로 가장 높게 나타났으며 11월에 9.7 kg으로 가장 낮게 나타났다. 인의 흡수량은 6월에 2.8 kg으로 가장 높게 나타났으며 11월에 0.7 kg으로 가장 낮게 나타났다. 인공습지로 이입되는 가축폐수의 질소 인 저감 효율은 각각 23.0, 59.1 %로 조사되었다. 본 연구결과는 향후 인공습지 내 오염물질 및 영양염류 순환 도출에 기여할 것으로 판단된다.

• 한국미생물·생명공학회지
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• 제18권4호
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• pp.401-405
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• 1990

5 혈청을 포함한 DMEM 배지에 갑상세포주 579를 연속배양하여 약 $5.7 \times 10^{-8}$g/h /cell에 해당하는 pro-UK의 비생산속도를 얻을 수 있었다. 또한 배지의 이동속도가 증가할 수록 glutamine의 소비속도가 증가하는 반면 ammonia 생산속도는 일정하게 유지되는, glutamine의 완전동화에의한 물질생산증가 현상을 나타냈다. 5mM의 glucose와 2mM의 glutamine, 포화용존 공기의 10에 해당하는 용존산소 및 pH 6.2의 maintenance 생육 조건하에서 약 15일간 유지시켜, $12\times 10^{-8}$g of pro-UK/h/cell의 최대 비생산속도와 0.226mg/g of glucose의 생산수율을 얻었으며, 이는 10ml/min의 배지 이동속도를 유지하는 연속배양 조건에서 매일 0.223mg의 pro-KU를 생산할 수 있을을 의미한다.

• Ocean and Polar Research
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• 제26권2호
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• pp.145-154
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• 2004

Surface energy and $CO_2$ fluxes have been measured over an ocean at Ieodo Ocean Research Station of KORDI since May 2003. Eddy covariance technique, which is a direct flux measurement, is used to quantitatively understand the interaction between the ocean surface and the atmospheric boundary layer. Although fluxes were continuously measured during the period from May 2003 to February 2004, the quality control of these data yielded <20% of data retrieval. The atmospheric stability did not show any distinct dirunal patterns and remained near-neutral to stable from May to June but mostly unstable during fall and winter in 2003. Sensible heat flux showed a good correlation with the difference between the sea water temperature and the air temperature. The maximum fluxes of sensible heat and latent heat were $120Wm^{-2}$ and $350Wm^{-2}$ respectively, with an averaged Bowen ratio of 0.2. The ocean around the tower absorbed $CO_2$ from the atmosphere and the uptake rates showed seasonal variations. Based our preliminary results, the daytime $CO_2$ flux was steady with an average of $-0.1 mgCO_2m^{-2}s^{-1}$ in summer and increased in winter. The nighttime $CO_2$ uptake was greater and fluctuating, reaching up to $-0.1 mgCO_2m^{-2}s^{-1}$ but these data require further examination due to weak turbulent mixing at nighttime. The magnitude of $CO_2$ flux was positively correlated with the half hourly changes in horizontal mean wind speed. Due to the paucity of quality data, further data collection is needed for more detailed analyses and interpretation.