Methane production from oleate: assessing the bioaugmentation potential of Syntrophomonas zehnderi. 
The potential for improving long-chain fatty acids (LCFA) conversion to methane was evaluated by bioaugmenting a non-acclimated anaerobic granular sludge with Syntrophomonas zehnderi.  Batch bioaugmentation assays were performed with and without the solid microcarrier sepiolite, using 1 mM oleate as sole carbon and energy source.  When S. zehnderi was added to the anaerobic sludge methane production from oleate was faster.  High methane yields, i.e. 89 ± 5% and 72 ± 1%, were observed in bioaugmented assays in the absence and presence of sepiolite, respectively.  Sepiolite stimulated a faster methane production from oleate and prevented the accumulation of acetate.  Acetoclastic activity was affected by oleate in the absence of sepiolite, where methane production rate was 26% lower than in assays with microcarrier.