Review
Biotechnology & Applied Microbiology
R. B. Costa, P. N. L. Lens, E. Foresti
Summary: Anaerobic technologies play a crucial role in sewage treatment and recovering marketable products from waste, but they often lead to methane oversaturation and lack of nitrogen removal. However, combining methane oxidation with denitrification processes can address both issues simultaneously.
CRITICAL REVIEWS IN BIOTECHNOLOGY
(2022)
Review
Environmental Sciences
Xuan Wang, Guo-Jun Xie, Ning Tian, Cheng-Cheng Dang, Chen Cai, Jie Ding, Bing-Feng Liu, De-Feng Xing, Nan-Qi Ren, Qilin Wang
Summary: This review comprehensively analyzes the redox cycles of manganese in the environment, and discusses its importance in greenhouse gas mitigation, nutrient loading, microbial bioremediation, and global biogeochemical cycles. The oxidation and reduction of manganese occur cyclically and simultaneously in water, soil, and sediment environments, coupled with microorganisms, providing promising opportunities for the remediation of contaminated environments.
SCIENCE OF THE TOTAL ENVIRONMENT
(2022)
Article
Geochemistry & Geophysics
Sean J. Loyd, Marissa N. Smirnoff
Summary: The importance of different diagenetic pathways in the formation of authigenic carbonate (AC) was studied, and it was found that anaerobic oxidation of methane (AOM) may be the most significant pathway. The impact of AOM on marine carbon budgets was evaluated.
Article
Engineering, Environmental
Feiyang Chen, Yuhui Niu, Zhirui An, Li Wu, Jie Zhou, Lin Qi, Guoyu Yin, Hongpo Dong, Xiaofei Li, Dengzhou Gao, Min Liu, Yanling Zheng, Lijun Hou
Summary: Tidal-induced shifts of n-DAMO activity and associated contribution to mitigating CH4 in intertidal wetlands were studied. The study found that the wetting-drying events caused by tidal cycling had significant effects on the abundance and activity of n-DAMO microbial communities. The presence of n-DAMO bacteria and archaea and their higher biodiversity under reflooded conditions were also observed. Structural equation modeling and correlation analysis indicated that n-DAMO activity was influenced by microbial abundance, substrate availability, and salt accumulation in sediment. This study provides valuable insights into accurately estimating CH4 emissions from intertidal wetlands under different tidal scenarios.
Article
Agricultural Engineering
Haiquan Dong, Liangchen Yue, Jun Cheng, Rongxin Xia, Junhu Zhou
Summary: Microbial electro-chemical degradation was proposed to enhance methane production from lipids in anaerobic digestion. Applying a voltage strengthened the beta-oxidation of lipids, promoting electron transfer and methane yield. The overall energy conversion efficiency in methane production increased due to microbial electrochemical degradation of lipids.
BIORESOURCE TECHNOLOGY
(2022)
Article
Engineering, Environmental
Chunshuang Liu, Tao Liu, Xiaoying Zheng, Jia Meng, Hui Chen, Zhiguo Yuan, Shihu Hu, Jianhua Guo
Summary: This study successfully embedded n-DAMO microorganisms into mature anammox granules to form combined anammox + n-DAMO granules, accelerating the granulation process of n-DAMO microorganisms. High-throughput sequencing of 16S rRNA genes revealed the distribution of anammox bacteria, n-DAMO bacteria, and n-DAMO archaea within the granules.
Article
Environmental Sciences
Youzhi Xin, Nengyou Wu, Zhilei Sun, Hongmei Wang, Ye Chen, Cuiling Xu, Wei Geng, Hong Cao, Xilin Zhang, Bin Zhai, Dawei Yan
Summary: This study analyzed the composition and distribution of bacteria and archaea in cold seep communities with different methane seepage intensity. The results showed that methane seepage intensity had an impact on microbial communities, and also suggested potential interactions between cold seepage and hydrothermal vent ecosystems.
SCIENCE OF THE TOTAL ENVIRONMENT
(2022)
Article
Environmental Sciences
Ke Zhang, Xiangling Wu, Jia Chen, Wei Wang, Hongbing Luo, Wei Chen, Dandan Ma, Xiaochan An, Zhaolan Wei
Summary: This study proposed an effective method to reduce methane emissions from constructed wetlands by introducing Mn-dependent anaerobic oxidation of methane (Mn-AOM) and microbial fuel cell (MFC) technology. The results showed that combining biological methods and bioelectrochemical methods can more effectively control methane emissions from constructed wetlands. Using Mn ore as the matrix and operating MFC effectively reduced methane emissions from constructed wetlands, with higher COD removal rate obtained in CW-MFC (Mn) during the 200 days of operation.
JOURNAL OF ENVIRONMENTAL MANAGEMENT
(2021)
Article
Environmental Sciences
Yanli Guo, Zhuang Chen, Shaohui Zhang
Summary: This study investigated a new startup strategy and operation performance for methane-fueled microbial fuel cells (MFCs), successfully starting up the MFC in a short time by pre-cultivating an adapted culture and optimizing conditions with increased concentrations of molybdenum and tungsten. The methane-fueled MFC achieved a maximum power density of 166 mW/m(3), demonstrating the effectiveness of the new startup strategy and operational conditions.
SCIENCE OF THE TOTAL ENVIRONMENT
(2021)
Article
Environmental Sciences
Lei Jiang, Yi-Xuan Chu, Xuan Zhang, Jing Wang, Xiaosong He, Chen-Yang Liu, Ting Chen, Ruo He
Summary: This study investigated the anaerobic oxidation of methane (AOM) activity and communities of methane-oxidizing bacteria in three informal landfills. The AOM rate was highest in the landfill with aeration, and the NO2--N content was positively correlated with the AOM rate. Gamma-Proteobacteria methanotrophs, especially Methylobacter, were abundant in the landfilled waste. The relative abundance of various methanotrophs was positively correlated with the contents of NO2--N in the landfilled waste samples.
ENVIRONMENTAL RESEARCH
(2022)
Article
Geochemistry & Geophysics
Sean J. Loyd, Patrick Meister, Bo Liu, Kevin Nichols, Frank A. Corsetti, Robert Raiswell, William Berelson, Graham Shields, Mark Hounslow, John W. F. Waldron, Bayne Westrick-Snapp, Jamie Hoffman
Summary: The early diagenesis of marine organic matter has a significant impact on Earth's surface chemistry, particularly in terms of carbon burial potential and the formation of authigenic minerals such as carbonate concretions. The formation of these concretions is closely related to microbial anaerobic diagenetic reactions that degrade organic matter and methane, with some reactions requiring an external oxidant. Changes in the oxidation state of Earth's oceans over time can therefore influence the mechanisms of concretion formation. Variability in the carbon isotope compositions of concretions indicates changes in diagenesis in shallow marine sediments, which is associated with the evolving redox landscape of Earth. Transport modeling helps to understand the potential effects of shifting redox chemistry and highlights the importance of organic carbon supply to the seafloor, marine sulfate concentrations, methane production, and external methane influx. The first clear evidence of anaerobic oxidation of methane-derived concretions occurred during the Carboniferous period, coinciding with the increased marine sulfate levels in the Paleozoic era. The lower variability observed in older concretions, particularly the Precambrian ones, may be attributed to a smaller marine sulfate reservoir and possibly elevated concentrations of marine dissolved inorganic carbon. The reasons behind the increase in maximum carbon isotope values over time are still not fully understood but may be related to isotopic equilibration between dissolved inorganic carbon and externally-derived methane. Ultimately, the isotopic record of concretions reflects changes in the availability of organic matter and the oxidation state of the marine environment, providing insights into the subsurface biosphere and diagenesis throughout geological time.
GEOCHIMICA ET COSMOCHIMICA ACTA
(2023)
Article
Environmental Sciences
Fernando Silva Bernardes, Mariana Antonio de Souza Pereira, Ismail Abdallah Ismail Hassan, Alinne Pereira de Castro, Kennedy Francis Roche, Paula Loureiro Paulo
Summary: The study aimed to examine the relationships between environmental conditions and microbial processes in an improved constructed wetland system. Physicochemical analysis and high-throughput DNA sequencing revealed differences in microbial communities and environmental conditions in various zones, with distinct microbial populations associated with different stages of organic carbon conversion and nutrient cycles. The system predominantly operated under anaerobic conditions, showing variations in redox potential and chemical oxygen demand along the greywater flow.
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
(2021)
Article
Engineering, Marine
Zilin Wei, Tianfu Xu, Songhua Shang, Hailong Tian, Yuqing Cao, Jiamei Wang, Zhenya Shi, Xiao Liu
Summary: Research in a bioreactor established a pore water environment in marine sediments, revealing that the formation mechanism of authigenic carbonates undergoes three stages: alkalinity rise, preferential formation of carbonate minerals, and formation of carbonate isomorphous series.
JOURNAL OF MARINE SCIENCE AND ENGINEERING
(2021)
Article
Engineering, Environmental
Tao Liu, Shihu Hu, Zhiguo Yuan, Jianhua Guo
Summary: The spatial distribution of microorganisms in a methane-based membrane biofilm reactor (MBfR) was experimentally revealed in this study, showing the dominance of anammox bacteria, nitrite/nitrate-dependent anaerobic methane oxidation (n-DAMO) bacteria, and n-DAMO archaea in different layers of the biofilm. It was found that microorganisms in the outer layer preferred substrates from wastewater, while those in the inner layer utilized substrates from the biofilm substratum. This study provides insights into microbial stratification in biofilm systems and potential applications of methane-based MBfRs in sewage treatment.
ENVIRONMENTAL SCIENCE & TECHNOLOGY
(2023)
Editorial Material
Microbiology
Lisa Y. Y. Stein
Summary: An anaerobic methanotrophic archaeon, 'Candidatus Methanoperedens nitroreducens', divides itself into two distinct populations in terms of morphology and function, allowing for adaptation and cross-species interactions in a dynamic bioreactor ecosystem.
NATURE MICROBIOLOGY
(2023)