Screening and Application of Ligninolytic Microbial Consortia to Enhance Aerobic Degradation of Solid Digestate

Microorganisms

Aude Bertrandias¹  Ulysse Brémond¹  Jean-Philippe Steyer²  Hélène Carrere²  Kim Milferstedt²  Valérie Bru-Adan²  Jérôme Hamelin²  Nicolas Bernet² 

[1] Air Liquide, Innovation Campus Paris, 1 Chemin de la Porte des Loges, 78354 Jouy-en-Josas, France;INRAE, Université de Montpellier, LBE, 102 Avenue des Étangs, 11100 Narbonne, France;

关键词: anaerobic digestion;    biogas;    solid digestate;    aerobic consortia;    lignin;    bioaugmentation;   

DOI  :  10.3390/microorganisms10020277

来源: DOAJ

【 摘 要 】

Recirculation of solid digestate through digesters has been demonstrated to be a potential simple strategy to increase continuous stirred-tank reactor biogas plant efficiency. This study extended this earlier work and investigated solid digestate post-treatment using liquid isolated ligninolytic aerobic consortia in order to increase methane recovery during the recirculation. Based on sampling in several natural environments, an enrichment and selection method was implemented using a Lab-scale Automated and Multiplexed (an)Aerobic Chemostat system to generate ligninolytic aerobic consortia. Then, obtained consortia were further cultivated under liquid form in bottles. Chitinophagia bacteria and Sordariomycetes fungi were the two dominant classes of microorganisms enriched through these steps. Finally, these consortia where mixed with the solid digestate before a short-term aerobic post-treatment. However, consortia addition did not increase the efficiency of aerobic post-treatment of solid digestate and lower methane yields were obtained in comparison to the untreated control. The main reason identified is the respiration of easily degradable fractions (e.g., sugars, proteins, amorphous cellulose) by the selected consortia. Thus, this paper highlights the difficulties of constraining microbial consortia to sole ligninolytic activities on complex feedstock, such as solid digestate, that does not only contain lignocellulosic structures.

【 授权许可】

Unknown