기포탑 반응기에서 Chlorella HA-1의 CO_2 고정화 특성

성기돈,이진석,신철승,김미선,박순철,김승욱 한국산업미생물학회 1998 한국미생물·생명공학회지 Vol.26 No.1

The characteristics of CO_2 fixaton by Chlorella HA-1 cultured in bubble columns were studied to achieve high photosynthetic rates per basal area. The influence of experimental conditions such as the diameter of a bubble column and gas flow rate, on photosynthesis of Chlorella HA-1 was investigated. The maximum productivity and the overall CO_2 fixation rate obtained in a 0.15 L bubble column was 1.09 g dry biomass/L-day and 1048 g CO_2/㎡-day, respectively. Light limitation has been observed in the bubble columns having a diameter larger than 3.5 ㎝. As the reactor volume increased, the decrease of the CO_2 fixation rate was remarkable. High gas flow rate was helpful to mitigate the light limitation problem. 수직 관형 반응기(기포탑)에서 담수성 미세조류인 Chlorella HS-1의 CO_2 고정화 특성을 조사하였다. Chlorella HA-1의 배양액은 균체 자체에 의한 음영효과(self-shading effect)로 균체의 농도가 증가하면 빛의 투과 깊이는 급격하게 감소하는 것으로 밝혀졌다. 기포탑 반응기에서의 균체 생산성은 반응기의 직경에 반비례하여 가장 작은 직경 2 ㎝ 반응기에서 균체 생산성과 CO_2 고정화 속도가 각각 1.097 g/ℓ와 1048 g CO_2/㎡-day로 가장 높았다. 그러나 직경 2 ㎝ 반응기의 경우 photoinhibition현상이 나타났으며 그 결과 최종 균체 농도는 직경 3.5 ㎝ 반응기의 7.84 g/ℓ에 비해 30% 낮은 5.65 g/ℓ이었다. 기포탑 반응기의 직경이 2 ㎝이상이면 CO_2 고정화 속도가 급격하게 떨어지는 것으로 밝혀졌다. 이와같은 CO_2 고정화 속도의 감소는 광합성에 필요한 빛이 반응기 내부로 충분히 전달되지 않아 대부분의 미세조류가 CO_2 고정화에 빛을 효율적으로 활용할수 없었기 때문으로 생각된다. 기포탑 반응기에 공급하는 CO_2 가스 유량을 증가시키면 미세조류의 생산성이 높아졌으며 반응기의 직경이 커질수록 생산성의 상승 효과는 뚜렷하였다. 이와같은 균체의 생산성 향상은 균체가 명-암영역으로 활발하게 이동하여 빛의 활용 효율을 높일 수 있었기 때문으로 생각된다. 따라서 반응기내 미세조류가 명-암 영역으로 활발하게 이동하도록 하는 장치 또는 운전기술의 적용이 필요함을 보여준다. The characteristics of CO_2 fixaton by Chlorella HA-1 cultured in bubble columns were studied to achieve high photosynthetic rates per basal area. The influence of experimental conditions such as the diameter of a bubble column and gas flow rate, on photosynthesis of Chlorella HA-1 was investigated. The maximum productivity and the overall CO_2 fixation rate obtained in a 0.15 L bubble column was 1.09 g dry biomass/L-day and 1048 g CO_2/㎡-day, respectively. Light limitation has been observed in the bubble columns having a diameter larger than 3.5 ㎝. As the reactor volume increased, the decrease of the CO_2 fixation rate was remarkable. High gas flow rate was helpful to mitigate the light limitation problem.

제주지역 주요 활엽수의 대기 중 CO₂ 흡수율과 수분이용효율의 계절적 변화

오순자,김현철,강희석,신창훈,고석찬,Oh, Soonja,Kim, Hyoun-Chol,Kang, Hee-Suk,Shin, Chang-Hoon,Koh, Seok Chan 한국환경과학회 2020 한국환경과학회지 Vol.29 No.2

Seasonal changes in the CO₂ fixation rate and water-use efficiency in the leaves of six evergreen and two deciduous broad-leaved tree species on Jeju Island, Korea, were measured using a portable photosynthesis analyzer, to identify which species are most efficient in taking up CO₂ from the air. The CO₂ fixation rate was high in the deciduous species in spring and summer and decreased in fall, whereas it was high in the evergreen species in summer and fall and decreased in winter. The rate remained high in the deciduous tree Prunus yedoensis from spring to fall (> 7.1 μmol CO₂/m₂/s) and in two evergreen trees, Castanopsis cuspidata var. sieboldii and Cinnamomum camphora, in summer and fall (7.0 9.9 μmol CO₂/㎡/s). Therefore, these tree species fix atmospheric CO₂ effectively. The water-use efficiency was higher in evergreen species than in deciduous species regardless of the season. Exceptionally, it was high in the deciduous species Zelkova serrata in spring and summer (> 100 μmol CO₂/mol H₂O), suggesting that Z. serrata is a useful tree for dry conditions due to its tolerance of water stress. The regressions of the CO₂ fixation rate versus the evaporation rate and stomatal conductance were linear and non-linear, respectively. This suggests that the stomatal activity of leaves plays an important part in CO₂ fixation of plants. In conclusion, C. cuspidata var. sieboldii, C. camphora, and P. yedoensis should be planted along roads or in urban spaces for the greening of cities and mitigation of CO₂ concentrations in the air.

차나무, 동백나무, 귤나무 잎에서 엽록소 형광 및 CO2 흡수능의 비교 분석

오순자 ( Soon Ja Oh ),이진호 ( Jin Ho Lee ),고광섭 ( Kwang Sup Ko ),고석찬 ( Seok Chan Koh ) 한국환경생물학회 2012 환경생물 : 환경생물학회지 Vol.30 No.2

본 연구는 차나무(Camellia sinensis L.)와 동백나무(C, japonica L.), 제주지역의 주요 과수작물인 귤나무(Citrus unshiu M.) 잎을 대상으로 엽록소형광과 CO2 흡수능을 비교 분석하여 탄소흡수원으로서의 가치를 평가하고자하였다. 차나무의 CO2 고정율은 같은 과의 동백나무보다 높고 과수작물인 귤나무와 유사하였다. 기공전도도 (gs)는 3종 모두 새벽에는 높고 이후 저녁 시간까지 계속하여 감소하였다. 엽육 내 CO2 농도 (Ci)는 3종 모두 새벽 (06:00)에 높고 낮에 감소하였다가 저녁에 다시 증가하는 경향을 보였으며, 잎의 증산율 (E)은 낮 시간에 높아 졌다가 저녁에 감소하였다. 차나무에서 광계II의 광화학적 효율(Fv/Fm)은 낮시간에 다소 낮아졌다가 저녁에 다시 증가하는 양상을 보였다. 이러한 낮시간의 Fv/Fm 감소는 광억제의 결과로 보이며 그 감소폭이 동백나무보다 적어 빛이나 고온 등에 내성을 가지고 있음을 알 수 있다. 엽면적당 활성상태의 반응중심의 상대적 밀도를 의미하는 RC/CS는 3종 모두 낮시간에 감소하였다. ABS/RC, TRo/RC, ETo/RC와 DIo/RC는 차나무와 동백나무에서 낮시간에 증가하였으며, 귤나무에서도 낮시간에 증가하였으나 유의성이 없는 것으로 나타났다. 일동화율은 차나무가 320.1 mmol m-2 d-1로 가장 높았으며, 귤나무와 동백나무는 각각 292.5 mmol m-2 d-1와 244.8 mmol m-2 d-1로 나타났다. 이상의 결과를 토대로 차나무는 광합성율이 높고 낮 시간의 광억제도 낮을 뿐만 아니라, 귤나무보다 수분요구량이 낮고 수분이용효율은 높아 탄소흡 수원으로서 유용한 작물수종인 것으로 보인다. The chlorophyll fluorescence and photosynthetic CO2 fixation capacity of leaves from three major crop trees found on Jeju Island, Camellia sinensis L., Camellia japonica L., and Citrus unshiu M., were analyzed. The photosynthetic CO2 fixation rate of C. sinensis was similar to that of C. unshiu, and much higher than that of C. japonica which belongs to the same genus. Stomatal conductance in the three species was high at dawn and low during daytime. The intercellular CO2 concentration of the three species was also high at dawn and decreased at midday. The transpiration rate showed an opposite trend from the intercellular CO2 concentration. The photochemical efficiencies of PSII (Fv/Fm) in C. sinensis were slightly lower at midday compared to the level at dawn and/or dusk. The decline in Fv/Fm of C. sinensis at midday was much smaller than that of C. japonica. These results indicate that C. sinensis is better acclimated to high levels of radiation under natural conditions in late summer, although its PSII reaction center was inhibited by strong radiation. Of the chlorophyll fluorescence parameters in the species, the RC/CS decreased significantly while the ABS/RC, TRo/RC, ETo/RC, and DIo/RC increased significantly at midday in late summer. However, C. unshiu did not show significant changes in these values depending on the time of day. Among the three species, the daily CO2 fixation rate in C. sinensis (320.1 mmol m-2 d-1) was the highest, followed by that of C. unshiu (292.5 mmol m-2 d-1) and C. japonica (244.8 mmol m-2 d-1). Thus, C. sinensis may be a valuable crop tree in terms of the uptake of CO2 under natural field conditions.

Improving the CO2 fixation rate by increasing flow rate of the flue gas from microalgae in a raceway pond

Jun Cheng,Zongbo Yang,Junhu Zhou,Kefa Cen 한국화학공학회 2018 Korean Journal of Chemical Engineering Vol.35 No.2

Residence time of flue gas bubbles with different solution velocities and the influence of NOX and SO2 from flue gas on pH values of culture solutions were analyzed based on large-scale raceway reactors. Microalgal growth and CO2 fixation rates were also investigated with different gas flow rates. Bubble residence time was ~1.1 s when the solution velocity was 20 cm/s. The NOX and SO2 effects on microalgal growth were negligible, although 66% NOX and 95% SO2 were captured by the microalgal solution. Microalgal biomass productivity increased from 10.3 to 14.1 g/m2/d when flue gas flow rate increased from 20 to 50m3/h. CO2 fixation and microalgae biomass productivity increased further from 26.3 to 31.9 g/m2/d and from 14.1 to 17.1 g/m2/d, respectively, upon increase of flue gas flow rate from 50 to 150m3/h.

CO2 fixation and lipid production by microalgal species

Srinivasa Reddy Ronda,Pavani Parupudi,Chandrika Kethineni,Pradip Babanrao Dhamole,Sandeep Vemula,Prasada Rao Allu,Mahendran Botlagunta,Sujana Kokilagadda 한국화학공학회 2016 Korean Journal of Chemical Engineering Vol.33 No.2

Microalgal species Nannochloropsis limnetica, Botryococcus braunii, and Stichococcus bacillaris were compared for their ability to grow, remove CO2, and accumulate lipids in their biomass under CO2-enriched atmosphere. Overall, N. limnetica outperformed the other two cultures and distinctly exhibited higher specific growth rate (0.999 d−1) and CO2 fixation rate (0.129 gL−1 d−1) with a high specific lipid yield (40% w/w). The volumetric CO2 fixation rate for all three species was validated with biomass productivity and mass transfer methods (P<0.005 and R2=0. 98). At 10% CO2, N. limnetica showed one-and-a-half times more carbon fixation efficiency over B. braunii, and S. bacillaris. On the other hand, total fatty acids of N. limnetica dispalyed an apparent increase in oleic acid. Whereas, under similar conditions, N. limnetica exhibited reduced eicosapentaenoic acid. These findings suggest that at high CO2 conditions, N. limnetica proved to be an efficient CO2 capture algal system and can be considered for biofuel applications.

최적 배양 조건을 이용한 CO2 제거 목적의 담수 미세조류 Parachlorella kessleri의 바이오매스 생산성 향상

김지훈,김지훈,홍선우,김진우,손병락,김미경,김용환,설진현,전수환 (사)한국해양바이오학회 2024 한국해양바이오학회지 Vol.16 No.1

This study attempted to improve the growth of the freshwater microalgae, Parachlorella kessleri, through the sequential optimization of culture conditions. This attempt aimed to enhance the microalgae's ability to fixate atmospheric CO2. Culture temperature and light intensity appropriate for microalgal growth were scanned using a high-throughput photobioreactor system. The supplied air flow rate varied from 0.05 to 0.3 vvm, and its effect on the growth rate of P. kessleri was determined. Next, sodium phosphate buffer was added to the culture medium (BG11) to enhance CO2 fixation by increasing the availability of CO2(HCO3-) in the culture medium. The results indicated that optimal culture temperature and light intensity were 20°C-25°C and 300 μE/m2/s, respectively. Growth rates of P. kessleri under various air flow rates highly depended on the increase of the culture's flow rate and pH which determines CO2 availability. Adding sodium phosphate buffer to BG11 to maintain a constant neutral pH (7.0) improved microalgal growth compared to control conditions (BG11 without sodium phosphate). These results indicate that the CO2 fixation rate in the air could be enhanced via the sequential optimization of microalgal culture conditions.

제주도 자생 참나무과 식물의 대기 중 CO2 흡수 능력의 비교분석

오순자 ( Soon Ja Oh ),신창훈 ( Chang Hoon Shin ),김철수 ( Chul Soo Kim ),강희석 ( Hee Suk Kang ),강경민 ( Kyeng Min Kang ),양윤희 ( Yun Hi Yang ),고석찬 ( Seok Chan Koh ) 한국환경과학회 2012 한국환경과학회지 Vol.21 No.1

The rate of photosynthesis (A) of leaves from 10 plant species (6 evergreen and 4 deciduous) of the family Fagaceae was measured using a portable photosynthesis analyzer, to examine which species take up CO2 most efficiently. Of the evergreen species, the photosynthetic rate of Castanopsis cuspidata var. sieboldii was highest, and remained above 82.1~106.4 μmol kg-1s-1 from July to November. Of the deciduous species, the photosynthetic rate of Quercus acutissima was higher than that of the other three species, and remained high at 83.5~116.6 μmol kg-1s-1 from September to November. The photosynthetic rate of the 10 species was positively correlated with stomatal conductance (gs) and transpiration rate (E). However, there was no correlation between photosynthetic rate and intercellular CO2 concentration (Ci), although there was a positive correlation just in three species (Q. gilva, Q. acutissima and Q. glauca). These results suggest that the CO2 fixation capacity of C. cuspidata var. sieboldii, an evergreen species, and Q. acutissima, a deciduous species, is significantly higher than that of the other species examined, and that photosynthesis is regulated by both stomatal conductance and transpiration. Therefore, C. cuspidata var. sieboldii and Q. acutissima may be valuable for the evaluation of carbon uptake in urban green spaces as well as in afforested areas.

고농도 아연 조건에서 수수-수단그라스 교잡종의 생장, 광합성 및 아연 제거능

오순자 ( Soonja Oh ),고석찬 ( Seok Chan Koh ) 한국환경과학회 2016 한국환경과학회지 Vol.25 No.8

Plant biomass, photosystem II (PSII) photochemical activity, photosynthetic function, and zinc (Zn) accumulation were investigated in a sorghum-sudangrass hybrid (Sorghum bicolor × S. sudanense) exposed to various Zn concentrations to determine the elimination capacity of Zn from soils. Plant growth and biomass of the sorghum-sudangrass hybrid decreased with increasing Zn concentration. Symptoms of Zn toxicity, i.e., withering and discoloration of old leaves, were found at Zn concentrations over 800 ppm. PSII photochemical activity, as indicated by the values of F_v/F_m and F_v/F<sub>o</sub, decreased significantly three days after exposure to Zn concentrations of 800 ppm or more. Photosynthetic CO₂c fixation rate (A) was high between Zn concentrations of 100-200 ppm (22.5 μmol CO₂·m^-2·s^-1), but it declined as Zn concentration increased. At Zn concentrations of 800 and 1600 ppm, A was 14.1 and 1.8 μmol CO₂·m^-2·s^-1 , respectively. The patterns of stomatal conductance (g^s), transpiration rate (E), and water use efficiency (WUE) were all similar to that of photosynthetic CO2 fixation rate, except for dark respiration (R^d), which showed an opposite pattern. Zn was accumulated in both above- and below-ground parts of plants, but was more in the below-ground parts. Magnesium (Mg) and iron (Fe) concentrations were significantly low in the leaves of plants, and symptoms of Mg or Fe deficiency, such as a decrease in the SPAD value, were found when plants were treated with Zn concentrations above 800 ppm. These results suggest that the sorghum-sudangrass hybrid is able to accumulate Zn to high level in plant body and eliminate it with its rapid growth and high biomass yield.

Optimization of culture conditions and comparison of biomass productivity among three microalgae

Geun Ho GIM,Young Mi LEE,Won duck KIM,Si Wouk KIM 한국생물공학회 2011 한국생물공학회 학술대회 Vol.2011 No.4