Prospecting Fungi For Methane Biofiltration Reveals High-Efficiency Capture By Dried Mycelia (Necromass)

Abstract

Fungi can improve biofiltration of hydrophobic pollutants by improving capture, a rate-limiting step in bioreactors. We prospected fungi alongside native biofilm preparations and relevant controls for their efficacy capturing methane using gas-phase biofilters. Using a batch incubation system, we found that Ganoderma lucidum performed best in single-strain trials. Building on this, we tested other Ganoderma species and found comparable efficacies. The advantages of Ganoderma and Pleurotus isolates were lost and native colonizers wood substrates were deployed in the field, irrespective of where they were deployed. This relates to a stress-tolerant rather than competitive life history strategy, where Ganoderma species are outcompeted in less stressful environments. We also tested an alternative way to present Ganoderma for filtration. Using protocols for culinary and biomaterial applications, we re-tested several fungi, including Lentinus edodes ‘shiitake.’ In these trials, we found surprisingly high efficacy with Ganoderma mycelia (84%) relative to activated carbon. These results suggest that Ganoderma species might best be utilized for biofiltration in dried form, effective in field conditions and potentially more amenable for biofiltration indoors.