In-Situ Extraction of Formate in a Biocatalytic System via Ion-Pair Formation Using Quaternary Ammonium Salts under Neutral Conditions
- 주제어 (키워드) In-situ extraction , Liquid-Liquid extraction , Formate , Quaternary ammonium salts (QASs) , Ion-pair formation
- 발행기관 서강대학교 일반대학원
- 지도교수 이진원
- 발행년도 2025
- 학위수여년월 2025. 8
- 학위명 석사
- 학과 및 전공 일반대학원 화공생명공학과
- 실제 URI http://www.dcollection.net/handler/sogang/000000082082
- UCI I804:11029-000000082082
- 본문언어 영어
- 저작권 서강대학교 논문은 저작권 보호를 받습니다.
초록 (요약문)
Product accumulation during biocatalytic processes often leads to feedback inhibition, thereby reducing catalytic efficiency and overall productivity. To address this limitation, we developed an in-situ liquid–liquid extraction (LLE) strategy for continuous formate removal via ion-pair formation using tetrabutylammonium bromide (TBAB) and 1- octanol under neutral pH conditions. To ensure biocompatibility, the stability and activity of Escherichia coli BL21 (expressing carbon monoxide dehydrogenase, CODH) and Methylobacterium extorquens ATCC 55366 (expressing formate dehydrogenase, FDH) were systematically evaluated in the presence of candidate organic solvents and quaternary ammonium salts (QASs). Among the tested combinations, the TBAB/1-octanol system showed the highest compatibility with the biocatalysts while enabling sustained formate production. Kinetic studies revealed that extraction equilibrium was reached within 60 minutes. Under optimized conditions (1:1 aqueous to organic phase ratio and 1:2 molar ratio of formate to TBAB), the extraction efficiency reached ~21–25%, requiring minimal chemical input. Additionally, back-extraction using 0.1 N NaOH enabled the recovery of up to 80% of sodium formate, maintaining phase stability. Overall, this work demonstrates a biocompatible and efficient biphasic extraction platform applicable to CO to formate conversion systems using whole-cell. This approach offers a scalable solution for continuous carbon valorization while mitigating product inhibition.
more목차
1. Introduction 1
2. Material and Methods 6
2.1. Materials 6
2.2. Whole-cell biocatalyst preparation 8
2.2.1. Activity measurement 8
2.2.2. Formate productivity analysis 9
2.3. Operation of LLE extraction system 10
2.4. Analytical methods 11
2.5. Extraction parameters 12
3. Results and Discussion 14
3.1. Effect of components in the extraction system on biocatalyst stability 14
3.1.1. Organic solvents 14
3.1.2. Quaternary Ammonium Salts (QASs) 17
3.2. Evaluation of extraction performance 20
3.2.1. Time-dependent extraction kinetics 20
3.2.2. Optimization of extraction efficiency 23
3.2.3. Estimation of extraction parameters 26
3.3. Back-Extraction 28
3.4. In-Situ system validation and process feasibility 31
4. Conclusion 34
5. Acknowledgement 36
6. References 37
