Xu Chao, Frigo-Vaz Benjamin, Goering Joshua, Wang Ping
Department of Bioproducts and Biosystems Engineering, University of Minnesota, St. Paul, Minnesota, USA.
Biotechnology Institute, University of Minnesota, St. Paul, Minnesota, USA.
Biotechnol Bioeng. 2023 May;120(5):1323-1333. doi: 10.1002/bit.28348. Epub 2023 Feb 21.
Herein we report the use of Pseudomonas putida F1 biofilms grown on carbonized cellulosic fibers to achieve biodegradation of airborne volatile organic compounds (VOCs) in the absence of any bulk aqueous-phase media. It is believed that direct exposure of gaseous VOC substrates to biomass may eliminate aqueous-phase mass transfer resistance and facilitate VOC capture and degradation. When tested with toluene vapor as a model VOC, the supported biofilm could grow optimally at 300 p.p.m. toluene and 80% relative humidity, with a specific growth rate of 0.425 day . During long-term VOC biodegradation tests in a tubular packed bed reactor, biofilms achieved a toluene degradation rate of 2.5 mg g h during the initial growth phase. Interestingly, the P. putida F1 film kept biodegrading activity even at the stationary nongrowth phase. The supported biofilms with a biomass loading of 20% (wt) could degrade toluene at a rate of 1.9 mg g h during the stationary phase, releasing CO at a rate of 6.4 mg g h at the same time (indicating 100% conversion of substrate carbon to CO ). All of these observations promised a new type of "dry" biofilm reactors for efficient degradation of toxic VOCs without involving a large amount of water.
在此，我们报道了利用在碳化纤维素纤维上生长的恶臭假单胞菌F1生物膜，在不存在任何大量水相介质的情况下实现空气中挥发性有机化合物（VOCs）的生物降解。据信，气态VOC底物直接暴露于生物质可能消除水相传质阻力，并促进VOC的捕获和降解。以甲苯蒸汽作为模型VOC进行测试时，负载型生物膜在300 ppm甲苯和80%相对湿度下可实现最佳生长，比生长速率为0.425天⁻¹。在管式填充床反应器中进行的长期VOC生物降解测试期间，生物膜在初始生长阶段实现了2.5 mg g⁻¹ h⁻¹的甲苯降解率。有趣的是，恶臭假单胞菌F1膜即使在静止的非生长阶段也保持生物降解活性。生物质负载量为20%（重量）的负载型生物膜在静止阶段可将甲苯以1.9 mg g⁻¹ h⁻¹的速率降解，同时以6.4 mg g⁻¹ h⁻¹的速率释放CO₂（表明底物碳100%转化为CO₂）。所有这些观察结果预示着一种新型的“干式”生物膜反应器，可用于高效降解有毒VOCs，而无需大量用水。
