| Title: | Effect of Temperature on Anaerobic Fermentation of Poplar Ethanol Wastewater: Performance and Microbial Communities |
| Author(s): | Yan X; Deng P; Ding T; Zhang Z; Li X; Wu Z; |
| Address: | "College of Materials Science and Engineering, Central South University of Forestry and Technology, Changsha, Hunan410004, China" |
| ISSN/ISBN: | 2470-1343 (Electronic) 2470-1343 (Linking) |
| Abstract: | "Temperature plays an important role in anaerobic digestion (AD), and different substrates have different optimum temperatures in AD. However, the effect of temperature on the performance of AD when cellulosic ethanol wastewater was used as a substrate was rarely reported. Therefore, the digestion characteristics of cellulosic ethanol wastewater at 25, 35, 45, and 55 degrees C were investigated, and the microbial communities of the sludge sample were analyzed after fermentation. The results showed that the cumulative methane production was the highest at 55 degrees C, 906.40 +/- 50.67 mL/g VS, which was 81.06, 72.42, and 13.33% higher than that at 25, 35, and 45 degrees C, respectively. The content of methane was 68.13, 49.26, 70.46, and 85.84% at the terminal period of fermentation at temperatures of 25, 35, 45, and 55 degrees C, respectively. The testing of volatile fatty acids (VFAs) indicated that the accumulation of VFAs did not occur when the fermentation was carried out at 25, 35, and 45 degrees C; however, the VFA content at 55 degrees C was much larger than that in the three groups (25, 35, and 45 degrees C), and the ratio of propionic acid to acetic acid was larger than 1.4 at the late stage of fermentation, so it inhibited the fermentation. The diversity of the microbial community indicated that the floral structure and metabolic pathway of fermentation were alike at 25 and 35 degrees C. Firmicutes and Proteobacteria were the main flora covering the 25-55 degrees C-based phylum or below it. The relative abundance of Methanosaeta was the highest when fermentation temperatures were 25 and 35 degrees C; however, its relative abundance decreased sharply and the relative abundance of Methanosarcina increased substantially when the temperature increased from 35 to 45 degrees C, which indicated that Methanosarcina can exist in higher temperatures. At the same time, hydrogenotrophic methanogens such as Methanoculleus and Methanothermobacter were dominant when fermentation temperatures were 45 and 55 degrees C, which indicated that the metabolic pathway changed from acetoclastic methanogenesis to hydrogenotrophic methanogenesis" |
| Notes: | "PubMed-not-MEDLINEYan, Xiaofan Deng, Pingping Ding, Tingting Zhang, Zuoyu Li, Xingong Wu, Zhiping eng 2023/02/24 ACS Omega. 2023 Jan 31; 8(6):5486-5496. doi: 10.1021/acsomega.2c06721. eCollection 2023 Feb 14" |
