| Autor: |
Pereira AR; Graduate Program in Environmental Engineering, Federal University of Ouro Preto, Campus Morro do Cruzeiro, Ouro Preto, Brazil., Assis NV; Graduate Program in Biotechnology, Federal University of Ouro Preto, Campus Morro do Cruzeiro, Ouro Preto, Brazil., Paranhos AGO; Graduate Program in Environmental Engineering, Federal University of Ouro Preto, Campus Morro do Cruzeiro, Ouro Preto, Brazil., Lima DRS; Graduate Program in Environmental Engineering, Federal University of Ouro Preto, Campus Morro do Cruzeiro, Ouro Preto, Brazil., Baeta BEL; Department of Chemistry, Federal University of Ouro Preto, Campus Morro do Cruzeiro, Ouro Preto, Brazil., Aquino SF; Department of Chemistry, Federal University of Ouro Preto, Campus Morro do Cruzeiro, Ouro Preto, Brazil., Silva SQ; Department of Biological Sciences, Federal University of Ouro Preto, Campus Morro do Cruzeiro, Ouro Preto, Brazil. |
| Abstrakt: |
In anaerobic digestion (AD), the choice of inoculum type seems to be relevant for methane production for complex substrates, such as lignocellulosic material. Previous work demonstrated that the addition of fresh manure and ruminal fluid to anaerobic sludge improved methane productivity and kinetics of AD of crude sugarcane bagasse (CSB). Considering that the improvement of methane production could be a result of a more adapted microbial community, the present study performed the Next Generation Sequencing analysis to identify changes in the microbiome of anaerobic sludge inoculum, resulting from fresh manure and ruminal fluid addition. In comparison with AD performed only with anaerobic sludge inoculum (50:50, U), accumulated methane production was 15% higher with anaerobic sludge plus ruminal fluid inoculum (50:50, UR) and even higher (68%) with anaerobic sludge with fresh bovine manure inoculum (50:50, UFM), reaching the value of 143 NmL CH4. g VS -1 . Clostridium species were highly abundant in all inocula, playing an important role during the hydrolysis and fermentation of CSB, and detoxifying potential inhibitors. Microbial composition also revealed the occurrence of Pseudomonas and Anaerobaculum at UFM inoculum that seem to have contributed to the higher methane production rate, mainly due to their hydrolytic and fermentative ability on lignocellulosic substrates. On the other hand, the presence of Alcaligenes might have had a negative effect on methane production due to their ability to perform methane oxidation. |
