메탄(CH4)과 일산화탄소(CO)와 같은C1-가스를 활용한 미생물 생물전환 공정은 지속 가능한 탄소자원 활용 기술로

주목받고 있으나, 낮은 기체 용해도와 물질전달 효율 저하가 주요 제한 요인으로 작용한다. 이를 극복하기 위해 생물

반응기 구조 최적화, 기체 확산 촉진 첨가제, 그리고 나노유체 적용을 통한 물질전달 성능 향상 전략이 연구되고 있다.

본 총설에서는 산업적 활용도가 높은 CH4 및 CO를 중심으로, 생물전환 공정에서 낮은 용해도와 세포독성 등의 물질

전달의 주요 장애요소를 지닌 이들 가스의 물질전달 향상을 위한 최신 연구 동향을 고찰하였다. 다양한 반응기 설계를

통해 기체 공급을 극대화하고, 계면활성제 및 전해질을 활용하여 기포 안정성을 조절하는 방안을 논의하였다. 또한, 나

노입자가 안정적으로 분산된 나노유체가 기체-액체 계면적을 증가시키고, 브라운 운동 및 대류 확산을 촉진하여 기체

용해도를 향상시키는 데 기여할 수 있음을 정리하였다. 특히, 생체친화적인 나노소재로 구성된 나노유체는 미생물과의

직접적인 상호작용을 통해 물질전달 저항을 줄이고, CH4 및 CO의 생물전환 효율을 개선하는 기능을 수행할 것으로

전망된다. 향후, C1-가스 물질전달 효율 향상 기술은 반응기 설계와 결합하여 물질전달 성능을 극대화하는 방향으로

발전할 것이며, 산업적 규모에서의 적용을 통해 보다 효율적인 C1-가스 전환 공정이 구현될 것으로 기대된다. 이를 통

해, 저탄소·친환경 바이오프로세스로의 전환이 가속화될 것이며, 생물전환 기술의 상업적 활용 범위도 확대될 것이다.

Microbial bioconversion of C1-gases, such as methane and carbon monoxide, is a promising approach for

sustainable carbon utilization but faces challenges due to poor gas solubility and mass-transfer limitations. To address

these issues, recent studies have explored enhancing mass transfer efficiency through modifications in bioreactor

configuration and design, gas diffusion-enhancing additives, and biocompatible nanofluids. This review provides an

overview of various bioreactor configurations and the role of surfactants and electrolytes in improving gas solubility and

enhancing the mass transfer coefficient (kLa). Additionally, nanofluids with stably suspended nanoparticles can increase

gas-liquid interfacial area, promote Brownian motion and convective diffusion, and enhance gas solubility. Biocompatible

nanofluids composed of functional bio-nanomaterials may further mitigate mass transfer limitations through direct

interactions with microorganisms, improving C1-gas bioconversion efficiency. Future developments will integrate

these strategies with advanced bioreactor configurations, enabling scalable and eco-friendly C1-gas microbial

bioconversion.

C1-gas bioconversion, Mass transfer, Bioreactor, Additive, Nanofluid

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