51
|
Incubation of innovative methanogenic communities to seed anaerobic digesters. Appl Microbiol Biotechnol 2016; 100:9795-9806. [PMID: 27717964 DOI: 10.1007/s00253-016-7875-z] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2016] [Revised: 09/06/2016] [Accepted: 09/20/2016] [Indexed: 10/20/2022]
Abstract
The methanogenic communities in alternative inocula and their potential to increase CH4 production in mesophilic and psychrophilic dairy manure-based anaerobic digesters were examined. Quantitative-PCR and terminal restriction fragment length polymorphism (T-RFLP) profiles were used to determine archaeal and methanogenic community changes when three inocula (wetland sediment (WS), landfill leachate (LL), and mesophilic digestate (MD)) were incubated at 15, 25, and 35 °C for 91 and 196 days. After each incubation period, the inocula were used in biochemical methane potential (BMP) tests at the incubation temperatures. There was no significant correlation between inoculum mcrA gene copy numbers and CH4 produced in BMP tests, suggesting that population size was not a distinguishing characteristic for predicting CH4 production. Archaeal composition in LL and WS reactors generally converged with MD reactors after incubation at 25 and 35 °C for 196 days. These MD reactors had high relative abundance of TRF 302, likely Methanosaetaceae, and low acetic acid (0.62-1.61 mM). At 15 °C incubation, most reactors were associated with high acetic acid (1.61-133.6 mM) and dominated by TRF 199, likely Methanosarcinaceae. The LL reactor incubated at 25 °C for 91 days had higher relative abundance of TRF 199 and produced significantly higher CH4 than WS and MD reactors in BMP test. In the future, it may be possible to create enrichment cultures that favor particular methanogens and use them as inoculum to benefit digesters at low mesophilic temperatures. Our data provides evidence that tailoring the archaeal community could benefit digesters operating under different conditions.
Collapse
|
52
|
Wu B, Wang X, Deng YY, He XL, Li ZW, Li Q, Qin H, Chen JT, He MX, Zhang M, Hu GQ, Yin XB. Adaption of microbial community during the start-up stage of a thermophilic anaerobic digester treating food waste. Biosci Biotechnol Biochem 2016; 80:2025-32. [DOI: 10.1080/09168451.2016.1191326] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
Abstract
A successful start-up enables acceleration of anaerobic digestion (AD) into steady state. The microbial community influences the AD performance during the start-up. To investigate how microbial communities changed during the start-up, microbial dynamics was analyzed via high-throughput sequencing in this study. The results confirmed that the AD was started up within 25 d. Thermophilic methanogens and bacterial members functioning in hydrolysis, acidogenesis, and syntrophic oxidation became predominant during the start-up stage, reflecting a quick adaption of microorganisms to operating conditions. Such predominance also indicated the great contribution of these members to the fast start-up of AD. Redundancy analysis confirmed that the bacterial abundance significantly correlated with AD conditions. The stable ratio of hydrogenotrophic methanogens to aceticlastic methanogens is also important to maintain the stability of the AD process. This work will be helpful to understand the contribution of microbial community to the start-up of AD.
Collapse
Affiliation(s)
- Bo Wu
- Biogas Institute of Ministry of Agriculture, Chengdu, China
| | - Xing Wang
- Biogas Institute of Ministry of Agriculture, Chengdu, China
- Graduate School of Chinese Academy of Agricultural Sciences, Beijing, China
| | - Ya-Yue Deng
- Biogas Institute of Ministry of Agriculture, Chengdu, China
| | - Xiao-Lan He
- Institute of Soil and Fertilizer, Sichuan Academy of Agricultural Sciences, Chengdu, China
| | - Zheng-Wei Li
- Biogas Institute of Ministry of Agriculture, Chengdu, China
- Graduate School of Chinese Academy of Agricultural Sciences, Beijing, China
| | - Qiang Li
- Biogas Institute of Ministry of Agriculture, Chengdu, China
| | - Han Qin
- Biogas Institute of Ministry of Agriculture, Chengdu, China
| | - Jing-Tao Chen
- Biogas Institute of Ministry of Agriculture, Chengdu, China
- Graduate School of Chinese Academy of Agricultural Sciences, Beijing, China
| | - Ming-Xiong He
- Biogas Institute of Ministry of Agriculture, Chengdu, China
| | - Min Zhang
- Biogas Institute of Ministry of Agriculture, Chengdu, China
| | - Guo-Quan Hu
- Biogas Institute of Ministry of Agriculture, Chengdu, China
| | - Xiao-Bo Yin
- Biogas Institute of Ministry of Agriculture, Chengdu, China
| |
Collapse
|
53
|
Archaea and Bacteria Acclimate to High Total Ammonia in a Methanogenic Reactor Treating Swine Waste. ARCHAEA-AN INTERNATIONAL MICROBIOLOGICAL JOURNAL 2016; 2016:4089684. [PMID: 27725793 PMCID: PMC5048046 DOI: 10.1155/2016/4089684] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/10/2016] [Accepted: 08/11/2016] [Indexed: 02/01/2023]
Abstract
Inhibition by ammonium at concentrations above 1000 mgN/L is known to harm the methanogenesis phase of anaerobic digestion. We anaerobically digested swine waste and achieved steady state COD-removal efficiency of around 52% with no fatty-acid or H2 accumulation. As the anaerobic microbial community adapted to the gradual increase of total ammonia-N (NH3-N) from 890 ± 295 to 2040 ± 30 mg/L, the Bacterial and Archaeal communities became less diverse. Phylotypes most closely related to hydrogenotrophic Methanoculleus (36.4%) and Methanobrevibacter (11.6%), along with acetoclastic Methanosaeta (29.3%), became the most abundant Archaeal sequences during acclimation. This was accompanied by a sharp increase in the relative abundances of phylotypes most closely related to acetogens and fatty-acid producers (Clostridium, Coprococcus, and Sphaerochaeta) and syntrophic fatty-acid Bacteria (Syntrophomonas, Clostridium, Clostridiaceae species, and Cloacamonaceae species) that have metabolic capabilities for butyrate and propionate fermentation, as well as for reverse acetogenesis. Our results provide evidence countering a prevailing theory that acetoclastic methanogens are selectively inhibited when the total ammonia-N concentration is greater than ~1000 mgN/L. Instead, acetoclastic and hydrogenotrophic methanogens coexisted in the presence of total ammonia-N of ~2000 mgN/L by establishing syntrophic relationships with fatty-acid fermenters, as well as homoacetogens able to carry out forward and reverse acetogenesis.
Collapse
|
54
|
De Vrieze J, Coma M, Debeuckelaere M, Van der Meeren P, Rabaey K. High salinity in molasses wastewaters shifts anaerobic digestion to carboxylate production. WATER RESEARCH 2016; 98:293-301. [PMID: 27110885 DOI: 10.1016/j.watres.2016.04.035] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/05/2016] [Revised: 04/13/2016] [Accepted: 04/15/2016] [Indexed: 05/16/2023]
Abstract
Biorefinery wastewaters are often treated by means of anaerobic digestion to produce biogas. Alternatively, these wastewaters can be fermented, leading to the formation of carboxylates. Here, we investigated how lab-scale upflow anaerobic sludge blanket reactors could be shifted to fermentation by changing organic loading rate, hydraulic retention time, pH, and salinity. A strong increase in volatile fatty acid concentration up to 40 g COD L(-1) was achieved through increasing salinity above 30 mS cm(-1), as well as a decrease in methane production by more than 90%, which could not be obtained by adjusting the other parameters, thus, indicating a clear shift from methane to carboxylate production. Microbial community analysis revealed a shift in bacterial community to lower evenness and richness values, following the increased salinity and VFA concentration during the fermentation process. A selective enrichment of the hydrogenotrophic Methanomicrobiales took place upon the shift to fermentation, despite a severe decrease in methane production. Particle size distribution revealed a strong degranulation of the sludge in the reactor, related to the high salinity, which resulted in a wash-out of the biomass. This research shows that salinity is a key parameter enabling a shift from methane to carboxylate production in a stable fermentation process.
Collapse
Affiliation(s)
- Jo De Vrieze
- Center for Microbial Ecology and Technology (CMET), Ghent University, Coupure Links 653, B-9000 Gent, Belgium
| | - Marta Coma
- Center for Microbial Ecology and Technology (CMET), Ghent University, Coupure Links 653, B-9000 Gent, Belgium
| | - Matthias Debeuckelaere
- Center for Microbial Ecology and Technology (CMET), Ghent University, Coupure Links 653, B-9000 Gent, Belgium
| | - Paul Van der Meeren
- Department of Applied Analytical and Physical Chemistry, Coupure Links 653, B-9000 Gent, Belgium
| | - Korneel Rabaey
- Center for Microbial Ecology and Technology (CMET), Ghent University, Coupure Links 653, B-9000 Gent, Belgium; Advanced Water Management Centre, The University of Queensland, Brisbane, Queensland 4072, Australia.
| |
Collapse
|
55
|
Microwave and ultrasound pre-treatments influence microbial community structure and digester performance in anaerobic digestion of waste activated sludge. Appl Microbiol Biotechnol 2016; 100:5339-52. [DOI: 10.1007/s00253-016-7321-2] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2015] [Revised: 01/10/2016] [Accepted: 01/12/2016] [Indexed: 01/29/2023]
|
56
|
Kong X, Xu S, Liu J, Li H, Zhao K, He L. Enhancing anaerobic digestion of high-pressure extruded food waste by inoculum optimization. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2016; 166:31-37. [PMID: 26468605 DOI: 10.1016/j.jenvman.2015.10.002] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/19/2015] [Revised: 09/30/2015] [Accepted: 10/02/2015] [Indexed: 06/05/2023]
Abstract
The inoculation for extruded food waste anaerobic digestion (AD) was optimized to improve methane (CH4) yield. The inoculum of acclimated anaerobic sludge resulted in high biodegradability, producing CH4 yields from 580 mLCH4 g(-1)·VSadded to 605 mLCH4 g(-1)·VSadded, with corresponding BDCH4 ranging from 90% to 94%. We also investigated inoculum to substrate ratios (ISRs). With regards to digested slurry as inoculum, we found that a decrease in ISR improved CH4 yield, while a lower ISR prolonged the lag time of the initial AD stage due to lipid inhibition caused by excessive food waste. These results demonstrate that minimal inocula are required to start the AD system for high-pressure extruded food waste because it is easily biodegraded. High ammonia concentration had a negative effect on CH4 production (i.e., when free ammonia nitrogen [FAN] increased from 20 to 30 mg L(-1) to 120-140 mg L(-1), the CH4 yield decreased by 25%), suggesting that FAN was a significant inhibitor in CH4 yield reduction. In terms of CH4 yield and lag time of the AD process, the optimal inoculation of digested slurry for the extruded food waste had an ISR of 0.33 with CH4 yield of 505 mLCH4 g(-1)VSadded, which was 20% higher than what was found for higher ISR controls of 2, 1 and 0.5.
Collapse
Affiliation(s)
- Xin Kong
- Key Laboratory for Solid Waste Management and Environment Safety, Ministry of Education of China, School of Environment, Tsinghua University, Beijing, 100084, China.
| | - Shuang Xu
- Key Laboratory for Solid Waste Management and Environment Safety, Ministry of Education of China, School of Environment, Tsinghua University, Beijing, 100084, China.
| | - Jianguo Liu
- Key Laboratory for Solid Waste Management and Environment Safety, Ministry of Education of China, School of Environment, Tsinghua University, Beijing, 100084, China.
| | - Huan Li
- Shenzhen Environmental Microbial Application and Risk Control Key Laboratory, Graduate School at Shenzhen, Tsinghua University, Shenzhen, 518055, China.
| | - Ke Zhao
- BESG Environmental Engineering Co., Ltd., Beijing Environment Sanitation Engineering Group Co., Ltd., Beijing, 100101, China.
| | - Liang He
- BESG Environmental Engineering Co., Ltd., Beijing Environment Sanitation Engineering Group Co., Ltd., Beijing, 100101, China
| |
Collapse
|
57
|
De Vrieze J, Regueiro L, Props R, Vilchez-Vargas R, Jáuregui R, Pieper DH, Lema JM, Carballa M. Presence does not imply activity: DNA and RNA patterns differ in response to salt perturbation in anaerobic digestion. BIOTECHNOLOGY FOR BIOFUELS 2016; 9:244. [PMID: 27843490 PMCID: PMC5103597 DOI: 10.1186/s13068-016-0652-5] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/04/2016] [Accepted: 10/20/2016] [Indexed: 05/11/2023]
Abstract
BACKGROUND The microbial community in anaerobic digestion is mainly monitored by means of DNA-based methods. This may lead to incorrect interpretation of the community parameters, because microbial abundance does not necessarily reflect activity. In this research, the difference between microbial community response on DNA (total community) and RNA (active community) based on the 16S rRNA (gene) with respect to salt concentration and response time was evaluated. RESULTS The application of higher NaCl concentrations resulted in a decrease in methane production. A stronger and faster response to salt concentration was observed on RNA level. This was reflected in terms of microbial community composition and organization, as richness, evenness, and overall diversity were differentially impacted. A higher divergence of community structure was observed on RNA level as well, indicating that total community composition depends on deterministic processes, while the active community is determined by stochastic processes. Methanosaeta was identified as the most abundant methanogen on DNA level, but its relative abundance decreased on RNA level, related to salt perturbation. CONCLUSIONS This research demonstrated the need for RNA-based community screening to obtain reliable information on actual community parameters and to identify key species that determine process stability.
Collapse
Affiliation(s)
- Jo De Vrieze
- Center for Microbial Ecology and Technology (CMET), Ghent University, Coupure Links 653, B-9000 Ghent, Belgium
- Department of Chemical Engineering, School of Engineering, University of Santiago de Compostela, Rúa Lope Gomez de Marzoa s/n, E-15782 Santiago de Compostela, Spain
| | - Leticia Regueiro
- Department of Chemical Engineering, School of Engineering, University of Santiago de Compostela, Rúa Lope Gomez de Marzoa s/n, E-15782 Santiago de Compostela, Spain
| | - Ruben Props
- Center for Microbial Ecology and Technology (CMET), Ghent University, Coupure Links 653, B-9000 Ghent, Belgium
| | - Ramiro Vilchez-Vargas
- Center for Microbial Ecology and Technology (CMET), Ghent University, Coupure Links 653, B-9000 Ghent, Belgium
| | - Ruy Jáuregui
- Microbial Interactions and Processes Research Group, Helmholtz Centre for Infection Research (HZI), Brunswick, Germany
- AgResearch, Tennent Drive, Palmerston North, 4442 New Zealand
| | - Dietmar H. Pieper
- Microbial Interactions and Processes Research Group, Helmholtz Centre for Infection Research (HZI), Brunswick, Germany
| | - Juan M. Lema
- Department of Chemical Engineering, School of Engineering, University of Santiago de Compostela, Rúa Lope Gomez de Marzoa s/n, E-15782 Santiago de Compostela, Spain
| | - Marta Carballa
- Department of Chemical Engineering, School of Engineering, University of Santiago de Compostela, Rúa Lope Gomez de Marzoa s/n, E-15782 Santiago de Compostela, Spain
| |
Collapse
|
58
|
Protocol for Start-Up and Operation of CSTR Biogas Processes. SPRINGER PROTOCOLS HANDBOOKS 2016. [DOI: 10.1007/8623_2016_214] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
|
59
|
Rui J, Li J, Zhang S, Yan X, Wang Y, Li X. The core populations and co-occurrence patterns of prokaryotic communities in household biogas digesters. BIOTECHNOLOGY FOR BIOFUELS 2015; 8:158. [PMID: 26413157 PMCID: PMC4582640 DOI: 10.1186/s13068-015-0339-3] [Citation(s) in RCA: 78] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/01/2015] [Accepted: 09/09/2015] [Indexed: 05/11/2023]
Abstract
BACKGROUND Household biogas digesters are widely used to harvest energy in rural areas of developing countries. Understanding core prokaryotic communities, their co-occurrence patterns, and their relationships to environmental factors is important to manage these small-scale anaerobic digestion systems effectively. In this study, 43 household biogas digesters were collected across eight provinces in China. Prokaryotic communities were investigated using 454 pyrosequencing of 16S rRNA genes. RESULTS Fourteen core genera and ten core OTUs were identified in household biogas digesters. They were mainly affiliated with the phylum Firmicutes, Synergistetes, Actinobacteria, Chloroflexi, and Spirochaetes. Core prokaryotic genera were mainly composed of Clostridium, Clostridium XI, Syntrophomonas, Cloacibacillus, Sedimentibacter, and Turicibacter. Prokaryotic communities in the 43 samples were clearly divided into two clusters. Cluster I was dominated by Clostridium, while Cluster II was dominated by members of Spirochaetes, Bacteroidales, Clostridia, and abundant syntrophs and methanogens. NH4 (+)-N and COD contributed significantly to the assembly of the prokaryotic community in Cluster I, while NH4 (+)-N, pH, and phosphate contributed significantly to Cluster II. Correlation-based network analysis showed that the prokaryotic communities in the biogas digesters were dominated by some functional modules. Cluster I was dominated by acetotrophic methanogenic modules and the Clostridium-driven primary fermentation module, while the network of Cluster II was dominated by hydrogenotrophic and acetogenic methanogenesis modules and multi-group-driven (Spirochaetes, Bacteroidales, and Clostridia) primary fermentation modules. The network of Cluster II was more complex and functionally redundant. CONCLUSIONS Prokaryotic communities identified in the household biogas digesters varied significantly and were affected by environmental factors, such as NH4 (+)-N, pH, and COD. However, core prokaryotic communities existed, and most of them were also dominant populations. Cosmopolitan OTUs tended to co-occur. Prokaryotic communities in biogas digesters were well organized by some functional modules. The modular structure of the prokaryotic community, which has functional redundancy, enhances the resistance against environmental stress and maintains digestion efficiency in the anaerobic digestion process.
Collapse
Affiliation(s)
- Junpeng Rui
- />Key Laboratory of Environmental and Applied Microbiology, Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu, 610041 China
- />Environmental Microbiology Key Laboratory of Sichuan Province, Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu, 610041 China
| | - Jiabao Li
- />Key Laboratory of Environmental and Applied Microbiology, Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu, 610041 China
- />Environmental Microbiology Key Laboratory of Sichuan Province, Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu, 610041 China
| | - Shiheng Zhang
- />Key Laboratory of Environmental and Applied Microbiology, Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu, 610041 China
- />Environmental Microbiology Key Laboratory of Sichuan Province, Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu, 610041 China
| | - Xuefeng Yan
- />Key Laboratory of Environmental and Applied Microbiology, Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu, 610041 China
- />Environmental Microbiology Key Laboratory of Sichuan Province, Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu, 610041 China
| | - Yuanpeng Wang
- />Department of Chemical and Biochemical Engineering, College of Chemistry and Chemical Engineering, Xiamen University, Fujian, 361005 China
| | - Xiangzhen Li
- />Key Laboratory of Environmental and Applied Microbiology, Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu, 610041 China
- />Environmental Microbiology Key Laboratory of Sichuan Province, Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu, 610041 China
| |
Collapse
|