Inoculum microbiome composition impacts fatty acid product profile from cellulosic feedstock

• Published in: Bioresource technology Vol. 323; p. 124532
• Main Authors: Rico, Jorge L., Reardon, Kenneth F., De Long, Susan K.
• Format: Journal Article
• Language: English
• Published: England Elsevier Ltd 01.03.2021
• Subjects: Anaerobic digestion; Anaerobiosis; Animals; Bioreactors; Cattle; Cellulose; Fatty Acids; Inoculum; Methane; Microbiome; Microbiota; Sewage; Fatty acids; Anaerobic digestion; Cellulose; Inoculum; Microbiome
• ISSN: 0960-8524; 1873-2976
• DOI: 10.1016/j.biortech.2020.124532

•Fatty acid production from cellulose was investigated for three microbial inocula.•Microbiome reactors remained phylogenatically distinct over time.•Microbial inocula source determined fatty acid production profile.•Bison rumen shows promise for increased production of butyric acid.•Specific taxa were statistically correlated to production of specific fatty acids. Conversion of organic wastes to fatty acids rather than methane through anaerobic digestion-based technologies has considerable promise. However, the relationships between microbiome structure and fatty acids produced from cellulosic feedstocks are not well understood. This study investigated the nature of those relationships for anaerobic digester sludge, bison rumen, and cattle rumen inocula grown on cellulose. Acetic acid production was highest in anaerobic sludge reactors, while propionic acid production was highest in cattle rumen reactors. Butyric and pentanoic acid were produced at the highest rates in bison rumen before Day 5. Reactor microbiomes remained distinct, despite identical operating conditions. Novel associations linked Alistipes with butyric acid production and Eubacterium nodatum and Clostridiales bacterium with pentanoic acid production. This study provides new insights into the ability of microbiomes to convert cellulose to different fatty acid mixtures and adds impetus for the rewiring of anaerobic digestion to generate high-value products.