Submitted to: Microbial Ecology International Symposium
Publication Type: Proceedings
Publication Acceptance Date: 8/25/2006
Publication Date: 8/25/2006
Citation: Ziemer, C.J., Morrison, M. 2006. Isolation of previously uncultured bacteria from long-term fermentations of swine feces fed cellulose. In: Proceedings of Microbial Ecology International Symposium, 11th International Symposium on Microbial Ecology, August 20-25, 2006, Vienna, Austria. 2006 CDROM. Interpretive Summary:
Technical Abstract: Bacteria found in the intestinal tract of pig affects the energy harvested from non-starch polysaccharides. Fermentation by bacteria excreted in the feces is the main source of malodorous compounds associated with swine manure. An asset to studying these procedures would be to have the bacteria available in culture. Long-term in vitro fermentations were designed to selectively enrich for bacteria that ferment cellulose as their carbohydrate source. Swine feces was collected immediately after excretion, transported to the laboratory and diluted 1 in 10 (w/v) in anaerobic phosphate buffered saline. After homogenizing for 3 min., 350 ml of slurry was added to fermentation vessels containing 350 ml of medium without added carbohydrates. Three g of cellulose was added to the vessel and the contents were allowed to sit for approximately 18 h after which medium flow was started. Fermenter contents were continuously mixed and sparged with nitrogen with temperature maintained at 38 degrees C and pH at 6.8. Medium flow rate was 0.03%/h and 3 g of cellulose was fed twice daily. Fermenters were maintained for eight weeks with samples taken for bacterial isolations on weeks 4, 6, and 8. Gram stain and cell morphology were determined prior to cell preservation and DNA extraction. Initial sequencing of 16S rRNA genes indicates that the majority of bacterial isolates (> 70%) are most closely related to sequences from cloned bacteria. With these bacteria now in culture we can study their phenotypic characteristics in relation to non-starch polysaccharide fermentation and the production of malodorous compounds.