• 대한환경공학회지
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• 제39권11호
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• pp.607-612
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• 2017

연소후 아민 $CO_2$ 포집공정에서 탄산수화 효소의 첨가에 따른 다양한 아민 흡수제의 $CO_2$ 흡수에 미치는 영향과 반응열을 평가하였다. 30 wt%의 MEA, AMP, DMEA, MDEA 수용액에 소의 적혈구에서 추출한 탄산무수화 효소 250 mg/L 첨가한 후 흡수속도를 분석한 결과, 모든 흡수제에서 $CO_2$ 흡수속도가 증가하였다. 특히, 1차아민인 MEA와 입체장애아민인 AMP보다는 3차아민인 DMEA와 MDEA에서 속도증진 효과가 컸다. 반응열량계를 이용하여 탄산무수화 효소 첨가후 흡수제(MEA, DMEA, MDEA)와 $CO_2$ 사이의 화학 반응 시 발생하는 반응열을 측정한 결과 효소 촉매의 첨가로 모든 흡수제의 반응열량이 낮아짐을 확인할 수 있었다. 특히, 연소후 아민 흡수제를 이용하는 이산화탄소 포집공정에 탈기 성능이 우수한 3차 아민 계열의 흡수제가 탄산무수화 효소 촉매 적용에 유리한 흡수제이며 이중 MDEA에서 효과가 가장 큼을 알 수 있었다.

• KSBB Journal
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• 제29권3호
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• pp.155-164
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• 2014

Succinic acid, a representative biomass-derived platform chemical, is a major fermentation product of Actinobacillus succinogenes. It is well known that carbon dioxide is consumed during the succinate fermentation, but the biochemical mechanism behind this phenomenon is not yet understood well. In this study, it was found that the addition of carbonic anhydrase (CA)s into media significantly enhances the succinic acid production by A. succinogenes during the fermentation supplied with carbon dioxide. It is likely that the (bi) carbonate produced by the CA activity from gaseous carbon dioxide is favoured by A. succinogenes for consumption and utilization. Therefore, the $MgCO_3$ requirement could be significantly reduced without compromising the succinate productivity. Furthermore, because of too high price of the commercial carbonic anhydrase, it was undertaken to economically overproduce a cyanobacterial carbonic anhydrase by the use of a recombinant Pichia pastoris. An expression vector system was constructed with the carbonic anhydrase gene PCR-cloned from Cyanobacterium Synechocystis sp., and introduced into P. pastoris for fermentation studies. About 95.9 g/L of succinic acid was produced in the production medium with 30 ppm of carbonic anhydrase, approximately 2 fold higher productivity compared to the parallel process with no supplementation of the enzyme. It is expected that this method can provide a valuable way of overcoming inefficiencies inherent in gas supply during $CO_2$-based bioprocesses like succinic acid fermentation.

• Ocean and Polar Research
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• 제44권3호
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• pp.209-220
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• 2022

Carbonic anhydrase (CA) is a key controller of the carbon concentrating mechanism (CCM), and is known to be affected by ambient pH and CO₂ compositions. Herein, we characterized three novel CAs genes (PmCA1, 2, and 3) from the marine dinoflagellate Prorocentrum minimum, and evaluated the relative expressions of the PmCAs and photosynthetic genes PmatpB and PmrbcL under different pH conditions. Each PmCA was predicted to have amino acid residues constituting the zinc binding site. With signal peptide, PmCA1 and PmCA2 were predicted to be intracellular CAs located in the cytoplasm and chloroplast membrane, respectively. On the other hand, PmCA3 was predicted to be extracellular CA located in the plasma membrane. Also, PmCA1 was classified into the beta family, and PmCA2 and PmCA3 were classified into the alpha family via phylogenic analysis. The photosynthesis efficiency of P. minimum was similar at pH 7 to 9, and decreased significantly at pH 6 and pH 10. Overall, relative gene expression levels of the three PmCAs decreased at low pH, and increased as pH increased. Photosynthesis related genes, PmatpB and PmrbcL, showed similar expression patterns to those of PmCAs. These results suggest that changes in seawater pH may affect photosynthesis and CO₂ metabolism in marine dinoflagellates.