• Journal of Microbiology and Biotechnology
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• 제15권3호
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• pp.461-465
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• 2005

Characteristics of biological $CO_2$ fixation by Chlorella sp. HA-1 were investigated in a semi-continuous and series reactor system using an internally illuminated photobioreactor to overcome shortcomings of physicochemical technologies such as adsorption and membrane separation. High $CO_2$ fixation rate was achieved in the semi-continuous reactor system, in which the dilution ratios of the culture medium were controlled. The average $CO_2$ fixation rate was maintained almost constantly when the dilution ratio increased by 0.1 increment from the initial value of 0.5. The total removal efficiency of $CO_2$ was enhanced by employing a series reactor system. The average $CO_2$ fixation rate increased until 4.013 g $CO_2\;day^{-1}$ in a series operation of four reactors, compared to 0.986 g $CO_2\;day^{-1}$ in a batch operation mode. The total $CO_2$ fixation rate was proportional to the number of reactors used in the series reactor system. In the series reactor system of semi-continuous operation, a large amount of $CO_2$ was removed continuously for 30 days. These results showed that the present reactor systems are efficient and economically feasible for a biological $CO_2$ fixation.

• KSBB Journal
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• 제18권4호
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• pp.340-345
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• 2003

본 연구에서는 대량으로 배출되는 이산화탄소를 고정화하기 위해서 lab 규모의 3 L 광생물 반응기(1)를 bench 규모의 40 L와 pilot 규모의 188 L로 스케일-업 했을 때 이산화탄소의 고정화 특성을 살펴보았다. 균체성장속도 즉, $CO_2$ 고정화 속도는 광생물 반응기가 스케일-업 됨에 따라 감소하였으며, 단위면적당 $CO_2$ 고정화 양은 40 L 광생물 반응기에서 530 g $CO_2$/$m^2$-day으로 가장 높았다. 반면, 총 $CO_2$ 고정화양은 반응기의 용량이 커짐에 따라 증가하였으며, 188 L 광생물 반응기에서 28.05 g $CO_2$/day를 얻었다. 광생물 반응기의 운전에 있어서 $CO_2$ 고정화속도의 향상은 단위면적당 $CO_2$ 고정화 양 및 총 $CO_2$ 고정화양을 증가시킨다. $CO_2$ 고정화속도에 영향을 미치는 운전인자 중에 가장 중요한 것은 광원으로 반응기의 스케일-업시 광원의 개수 및 배열을 조절함으로써 용량이 커짐에 따라 저감되는 $CO_2$ 고정화속도를 증가시킬 수 있었다. 또한 향후 스케일-업된 광생물 반응기에서의 물질전달 현상에 관한 연구를 동반함으로써 보다 높은 $CO_2$ 고정화속도를 얻을 수 있을 것으로 판단된다.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2000년도 추계학술발표대회 및 bio-venture fair
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• pp.455-456
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• 2000

Characteristics of $CO_2$ fixation by Chlorella sp. HA-1 were studied in a semi-continuous mode in a series operation. A high $CO_2$ fixation rate for a long time was obtained, when the method of semi-continuous mode was employed, in which the controlling parameter was the dilution ratio. A constant $CO_2$ fixation rate was maintained even when the dilution ratio was increased with the increment of 0.1 at the initial value of 0.5. The method of series operation was used to improve the efficiency of $CO_2$ fixation. The total amount of $CO_2$ fixation was proportion to the number of reactor in series operation.

• Journal of Plant Biology
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• 제25권3호
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• pp.105-111
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• 1982

These studies were undertaken to elucidate the reasons for the low productivity of ginseng by comparing the rate of $CO_2$-fixation and photorespiration, variation in the amounts of intermediates and enzyme activities of glycolate oxidase and catalase in ginseng with those of potato. The ability of $CO_2$-fixation in ginseng was found to be one half of that of potato and there were significant differences between those two plants in the rate of $^{14}C$ incorporated into glutamate, aspartate, malate and 3-PGA, but little differences in P-glycolate, glycolate, serine and glycine. The ratio of photorespiration to dark respiration and the activities of glycolate oxidase and catalase in the two species were about same, but ginseng showed higher ratio in photorespiration to total $CO_2$-fixation than potato did. These results indicated that the low productivity of ginseng may resulted from the low $CO_2$-fixation ability and high rate of photorespiration.

• Journal of Plant Biology
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• 제31권4호
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• pp.277-288
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• 1988

The effects of ammonium ion and glutamate on CO2 fixation abilities and related carbon metabolism were investigated in pea (Pisum sativum L. cv. Sparkle) leaf discs under conditions favoring photorespiration (21% O2, 0.03% CO2) and nonphotorespiration (5% O2, 0.03% CO2). A concentration of more than 10 mM of NH4+ decreased the photosynthetic CO2 fixation and those inhibitory effects were more remarkable in 21% O2 than in 5% O2 conditions. The effect of glutamate on CO2 fixation was found to be independent of the O2 level, as glutamate increased the CO2 fixation under both 21% and 5% O2 conditions. L-methionine-dl-sulfoximine, an irreversible inhibitor of glutamate synthetase, however, inhibited the CO2 fixation markedly under 21% O2, but did not affect it under 5% O2 conditions. The treatment with NH4+ elevated the relative amounts of 14C incorporated into soluble components from 14CO2 with no relation to O2 levels, while glutamate increased 14C into insoluble components and neutral sugars. Glutamate, especially, seemed to stmulate the biosynthesis of starch under 5% O2 condition. These results indicated that NH4+ stimulated the degradation of sugar or starch and this proposal was confirmed by the increasing of pyruvate kinase activity in leaf discs treated with ammonium ion.

• Biotechnology and Bioprocess Engineering:BBE
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• 제11권6호
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• pp.484-488
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• 2006

Alteration of illumination with optimum carbon dioxide fixation-based curve in this research successfully enhanced the $CO_{2}-fixation\;(q_CO_{2}$ capability of Chlorella vulgaris Buitenzorg cultivated in a bubble column photo bioreactor. The level of $CO_{2}$ fixation was up to 1.91 times that observed from cultivation with intensification of illumination on an optimum growth-based curve. During 144 h of cultivation, alteration of light intensity on an optimum $CO_{2}-fixation-based$ curve produced a $q_CO_{2}$ of $12.8\;h^{-1}$. Meanwhile, alteration of light intensity with a growth-based curve only produced a $q_CO_{2}$ of $6.68\;h^{-1}$. Increases in light intensity based on a curve of optimum $CO_{2}-fixation$ produced a final cell concentration of about 5.78 g/L. Both cultivation methods were carried out under ambient pressure at a temperature of $29^{\circ}C$ with a superficial gas velocity of $2.4\;m/h(U_{G}$. Cells were grown on Beneck medium in a 1.0 L Bubble Column Photo bioreactor illuminated by a Phillips Halogen Lamp (20 W/12 V/50 Hz). The inlet gas had a carbon dioxide content of 10%.

• 한국에너지공학회:학술대회논문집
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• 한국에너지공학회 1995년도 춘계학술발표회 초록집
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• pp.82-87
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• 1995

Carbon dioxide fixation by microalgae has several advantages such as no requirements for the pretreatment over phycal and/or chemical $CO_2$ fixation processes. Chlorella sp. HA-1, fresh algae. and Chlorococcum littorale. marine algae, were used to do $CO_2$ fixation work. The experimental parameters were light intensity and $CO_2$ concentration. Chlorella sp. HA-1 has the maximum growth rate at 8 Klux and 10% $CO_2$ concentration. Chlorococcum littorale showed the maximum growth at similar conditions. The results indicated the feasibility of the Chlorella HA-1 and Chlorococcum littorale for mass cultivation using flue gas.

• KSBB Journal
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• 제14권6호
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• pp.742-746
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• 1999

새로운 형태의 내부조사형 광생물반응기에서 Chlorella sp. HA-1의 이산화탄소 고정화 특성을 살펴보았다. 높은 이산화탄소 농도에서 균체를 적응시켜 10%와 20%(v/v) 이산화탄소 농도 모두에서 내성을 가지도록 하였다. 그리고 조도, 초기균체농도, pH 등을 조절하여 이산화탄소 고정화양, 372 $gCO_2/m^2{\cdot}day$을 얻었다. 또한 장시간 동안 지속적으로 배출되는 이산화탄소를 제거하기 위한 운전 방법으로 반연속식 배양방법을 사용하여 희석비를 0.1씩 증가시켰을 때 각 단계마다 균체성장속도를 일정하게 유지하는 결과를 얻었다.

• KSBB Journal
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• 제13권1호
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• pp.101-107
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• 1998

광합성 미생물의 고농도 배양에 의한 이산화탄소 고정능에 대한 기초 연구로써 관형 광생물반응기를 이용하여 이산화탄소 조성 및 초기균체농도에 따른 성장 경향을 보았다 배지의 pH가 지어되고 있는 조건하에서 20% 이산화탄소 혼합공기가 공급되는 조건에서도 성장이 이루어졌다 $45.5{\mu}E/m^2{\cdot}s$의 광강도에서 5% 이산화탄소 혼합공기 조성과 0.45 g/L의 초기균체농도에서 성장속도가 가장 우수하였으며, 비성장속도는 0.0258 $h^{-1}$를 나타냈고, 단위 시간당 균체생성량은 0.278 g/L . day 이다. 관형 반응기에서 최대균체농도는 2.03 g/L 까지 배양되었다. 배양된 균체의 원소성분분석을 통하여 Synechocystis PCC 6803의 분자식은 $C_{1.0}H_{2.022}N_{0.194}O_{0.443}S_{0.002}$로 계산되었고, 이산화탄소 고정화속도는 0.482g-$C0_2/L$ . day의 결과를 얻었다.

• Biotechnology and Bioprocess Engineering:BBE
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• 제8권6호
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• pp.354-359
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• 2003

$CO_2$fixation by microalgae has emerged as a promising option for $CO_2$mitigation. In-tensive research work has been carried out to develop a feasible system for removing $CO_2$from industrial exhaust gases. However, there are still several challenging points to overcome in order to make the process more practical. In this paper, recent research activities on three key technologies of biological $CO_2$fixation, an identification of a suitable algal strain, development of high efficient photobioreactor and utilization of algal cells produced, are described. Finally the barriers, progress, and prospects of commercially developing a biological $CO_2$fixation process are summarized.