Horses and several other herbivores may be harboring useful bacteria for biofuel production, research suggests.
Chunlei Yang, a researcher from Zhejiang University in China, conducted a study to explore acetogen communities in the gut of herbivores and their potential role in synthetic gas fermentation.
Acetogens are microorganisms that generate acetate as an end product of anaerobic respiration or fermentation.
Yang noted that large and diverse acetogen populations exist in the gut of herbivores, but they are distributed differently in ruminants compared to monogastric herbivores.
Yang investigated the composition of acetogen populations in cow and sheep rumens, rabbit ceca, and horse feces, and looked at their ability to convert hydrogen to other compounds as part of their metabolism.
The acetogens found in horses and rabbits were more diverse than those in cows and sheep, suggesting that the host species played an important role in shaping gut acetogen populations.
Acetogen enrichments from the four species tested showed good capacity to use hydrogen, with acetate as the major end product. Minor propionate, butyrate, and isovalerate were also produced.
“These short chain fatty acids are important precursors for the synthesis of biofuel products, suggesting that gut contents of herbivores may be promising sources for harvesting functional acetogens for biofuel production,” Yang concluded in his report, published in the journal Fermentation.
To develop such waste for bulk biofuel and chemical production, considerable effort would have to be made to explore suitable fermentation conditions or methods, he added.
Acetogen Communities in the Gut of Herbivores and Their Potential Role in Syngas Fermentation
Chunlei Yang. Fermentation 2018, 4(2), 40; doi:10.3390/fermentation4020040