Cultivation Strategy for Biological Ectoine Production using Methylotuvimicrobium alcaliphilum 20Z under Various Methane Gas Compositions
- 주제어 (키워드) Methylotuvimicrobium alcaliphilum 20Z , ectoine production , industrial CH4 gases , cultivation strategy
- 발행기관 서강대학교 일반대학원
- 지도교수 이진원
- 발행년도 2025
- 학위수여년월 2025. 2
- 학위명 석사
- 학과 및 전공 일반대학원 화공생명공학과
- 실제 URI http://www.dcollection.net/handler/sogang/000000079735
- UCI I804:11029-000000079735
- 본문언어 한국어
- 저작권 서강대학교 논문은 저작권 보호를 받습니다.
초록 (요약문)
Methanotroph-based CH4 conversion technologies are being studied due to its environmental friendliness. This study suggested optimal cultivation methods and comprehensive analysis of ectoine production using Methylotuvimicrobium alcaliphilum 20Z for various industrial CH4 sources and focused on distinguishing between the “dual- functions” of methanotrophs. The optimal O2/CH4 ratio for extremely different CH4 concentrations was explored and experimentally proven using fermenter-scale experiments. As a result, for the high CH4 concentration, ectoine concentration can be maximized at O2/CH4 ratio of 1, reaching 33.8 mg/L·h suggesting that the focus should be on “metabolites production”. In contrast , for the low CH4 concentration, changing from O2/CH4 ratio of 4 to 1 slightly increased the ectoine concentration from 3.9 to 7.5 mg/L·h, but the CH4 conversion rate decreased significantly from 50% to 20% while favoring the “CH4 removal”. In the case of biogas containing CO2, effective pH control is crucial, and the increase in Na+ ion concentration must be managed by continuous operation at a high dilution rate of 19.8 mg/L·h, which maximizing metabolite production. This study provides performance indicators for various industrial CH4 sources and offers operational guidance and evaluation methods, advancing the development of sustainable CH4 conversion technologies for high-value products.
more목차
1. Introduction 11
2. Material and Methods 15
2.1. Bacterial strain and medium 15
2.2. Cultivation 16
2.2.1. Flask cultivation 16
2.2.2. Fermeter cultivation 17
2.3. Analytical methods 18
2.4. Mathematical model 19
2.4.1. Kinetic modeling 21
2.4.2. Reactor modeling 23
3. Results and Discussion 25
3.1. Model prediction and experimental validation 25
3.1.1. Parameter estimation 25
3.1.2. Performance estimation of ectoine production 27
3.2. Flask cultivation for various CH4 concentration 31
3.3. Fermenter validation of various industrial CH4 sources 32
3.3.1. High concentration case 32
3.3.2. Low concentration case 35
3.3.3. Biogas case 39
3.4. Comprehensive analysis based on performance indicators of methanotroph-based CH4 conversion 44
4. Conclusion 49
5. Acknowledgement 51
6. References 52