Anaerobic biological decomposition of organic matter is ubiquitous in Nature wherever anaerobic environments prevail,and is catalysed by hydrolytic,fermentative,acetogenic,methanogenic,and various other groups.It is a...Anaerobic biological decomposition of organic matter is ubiquitous in Nature wherever anaerobic environments prevail,and is catalysed by hydrolytic,fermentative,acetogenic,methanogenic,and various other groups.It is also harnessed in innovative ways in engineered systems that may rely on small(0.1-4.0 mm),spherical,anaerobic granules.These biofilms are crucial to the operational success of a range of widely applied engineered-ecosystems designed for wastewater treatment.The structure and function of granule microbiomes underpin their utility.Here,granules were separated into ten size fractions(proxies for age),hypothesizing that small granules are‘young’and larger ones are‘old’.Gradients were observed across size in terms of volatile solids,density,settleability,biofilm morphology,methanogenic activity,and profiles of extracellular polymeric substances,suggesting ongoing development of physicochemical characteristics as granules develop.Short-read amplicon sequencing indicated a negative relationship between granule size and community diversity.Furthermore,as size increased,the methanogenic archaea dominated the microbiome.Small granules were found to harbour a sub-group of highly specific taxa,and the identification of generalists and specialists may point to substantial resilience of the microbiome.The findings of this study indicate opportunities for precision management of wastewater treatment systems.They suggest that size is an important indicator for aggregate utility e size may,indeed,determine many of the characteristics of both the individual-granule microbiomes and the overall function of a wastewater treatment system.展开更多
The industrial adoption of microbial electrosynthesis(MES)is hindered by high overpotentials deriving from low electrolyte conductivity and inefficient cell designs.In this study,a mixed microbial consortium originati...The industrial adoption of microbial electrosynthesis(MES)is hindered by high overpotentials deriving from low electrolyte conductivity and inefficient cell designs.In this study,a mixed microbial consortium originating from an anaerobic digester operated under saline conditions(∼13 g L^(−1)NaCl)was adapted for acetate production from bicarbonate in galvanostatic(0.25 mA cm^(−2))H-type cells at 5,10,15,or 20 g L^(−1)NaCl concentration.The acetogenic communities were successfully enriched only at 5 and 10 g L^(−1)NaCl,revealing an inhibitory threshold of about 6 g L^(−1)Na^(+).The enriched planktonic communities were then used as inoculum for 3D printed,three-chamber cells equipped with a gas diffusion biocathode.The cells were fed with CO_(2)gas and operated galvanostatically(0.25 or 1.00 mA cm^(−2)).The highest production rate of 55.4 g m^(−2) d^(−1)(0.89 g L^(−1)d^(−1)),with 82.4%Coulombic efficiency,was obtained at 5 g L^(−1)NaCl concentration and 1 mA cm^(−2)applied current,achieving an average acetate production of 44.7 kg MWh−1.Scanning electron microscopy and 16S rRNA sequencing analysis confirmed the formation of a cathodic biofilm dominated by Acetobacterium sp.Finally,three 3D printed cells were hydraulically connected in series to simulate an MES stack,achieving three-fold production rates than with the single cell at 0.25 mA cm^(−2).This confirms that three-chamber MES cells are an efficient and scalable technology for CO_(2)bio-electro recycling to acetate and that moderate saline conditions(5 g L^(−1)NaCl)can help reduce their power demand while preserving the activity of acetogens.展开更多
Agriculture is essential for providing food and maintaining food security while concurrently delivering multiple other ecosystem services. However,agricultural systems are generally a net source of greenhouse gases an...Agriculture is essential for providing food and maintaining food security while concurrently delivering multiple other ecosystem services. However,agricultural systems are generally a net source of greenhouse gases and ammonia. They, therefore, need to substantively contribute to climate change mitigation and net zero ambitions. It is widely acknowledged that there is a need to further reduce and mitigate emissions across sectors, including agriculture to address the climate emergency and emissions gap. This discussion paper outlines a collation of opinions from a range of experts within agricultural research and advisory roles following a greenhouse gas and ammonia emission mitigation workshop held in the UK in March 2022. The meeting identified the top mitigation priorities within the UK's agricultural sector to achieve reductions in greenhouse gases and ammonia that are compatible with policy targets. In addition, experts provided an overview of what they believe are the key knowledge gaps, future opportunities and cobenefits to mitigation practices as well as indicating the potential barriers to uptake for mitigation scenarios discussed.展开更多
基金supported by Erasmus and by the University of Turin and NUI Galway.UZI was funded by NERC IRF NE/L011956/1 and EPSRC EP/V030515/1.GC and AT were supported by a European Research Council Starting Grant(3C-BIOTECH 261330)and a Science Foundation Ireland Career Development Award to GC.AT was further supported by a Thomas Crawford Hayes bursary from NUI Galway,and to visit IB and GG by a Short-Term Scientific Mission grant through the EU COST Action 1302.VOF and AT were also financially supported by grants from the Higher Education Authority(HEA)of Ireland through:the Programme for Research at Third Level Institutions,Cycle 5(PRTLI-5),co-funded by the European Regional Development Fund(ERDF)the Enterprise Ireland Technology Centres Programme(TC/2014/0016)and Science Foundation Ireland(14/IA/2371 and 16/RC/3889).
文摘Anaerobic biological decomposition of organic matter is ubiquitous in Nature wherever anaerobic environments prevail,and is catalysed by hydrolytic,fermentative,acetogenic,methanogenic,and various other groups.It is also harnessed in innovative ways in engineered systems that may rely on small(0.1-4.0 mm),spherical,anaerobic granules.These biofilms are crucial to the operational success of a range of widely applied engineered-ecosystems designed for wastewater treatment.The structure and function of granule microbiomes underpin their utility.Here,granules were separated into ten size fractions(proxies for age),hypothesizing that small granules are‘young’and larger ones are‘old’.Gradients were observed across size in terms of volatile solids,density,settleability,biofilm morphology,methanogenic activity,and profiles of extracellular polymeric substances,suggesting ongoing development of physicochemical characteristics as granules develop.Short-read amplicon sequencing indicated a negative relationship between granule size and community diversity.Furthermore,as size increased,the methanogenic archaea dominated the microbiome.Small granules were found to harbour a sub-group of highly specific taxa,and the identification of generalists and specialists may point to substantial resilience of the microbiome.The findings of this study indicate opportunities for precision management of wastewater treatment systems.They suggest that size is an important indicator for aggregate utility e size may,indeed,determine many of the characteristics of both the individual-granule microbiomes and the overall function of a wastewater treatment system.
基金This work was performed on the framework of the Science Foundation Ireland(SFI)Pathfinder Award on“Hybrid Bio-Solar Reactors for wastewater treatment and CO_(2)recycling”(award nr.19/FIP/ZE/7572 PF)PD is supported by the European Union's Horizon 2020 research and innovation programme under the Marie Skłodowska-Curie grant agreement,project ATMESPHERE,No 101029266.SP is a Serra Hunter Fellow(UdG-AG-575)+4 种基金acknowledges the funding from the ICREA Academia award.LEQUIA has been recognised as a consolidated research group by the Catalan Government(2021-SGR-01352)UZI is supported by EPSRC(EP/P029329/1 and EP/V030515/1)VOF is supported by the Enterprise Ireland Technology Centres Programme(TC/2014/0016)Science Foundation Ireland(14/IA/2371,19/FFP/6746 and 16/RC/3889)DP acknowledges the support of the VIVALDI project that has received funding from the European Union's Horizon 2020 research and innovation program under grant agreement 101000441.
文摘The industrial adoption of microbial electrosynthesis(MES)is hindered by high overpotentials deriving from low electrolyte conductivity and inefficient cell designs.In this study,a mixed microbial consortium originating from an anaerobic digester operated under saline conditions(∼13 g L^(−1)NaCl)was adapted for acetate production from bicarbonate in galvanostatic(0.25 mA cm^(−2))H-type cells at 5,10,15,or 20 g L^(−1)NaCl concentration.The acetogenic communities were successfully enriched only at 5 and 10 g L^(−1)NaCl,revealing an inhibitory threshold of about 6 g L^(−1)Na^(+).The enriched planktonic communities were then used as inoculum for 3D printed,three-chamber cells equipped with a gas diffusion biocathode.The cells were fed with CO_(2)gas and operated galvanostatically(0.25 or 1.00 mA cm^(−2)).The highest production rate of 55.4 g m^(−2) d^(−1)(0.89 g L^(−1)d^(−1)),with 82.4%Coulombic efficiency,was obtained at 5 g L^(−1)NaCl concentration and 1 mA cm^(−2)applied current,achieving an average acetate production of 44.7 kg MWh−1.Scanning electron microscopy and 16S rRNA sequencing analysis confirmed the formation of a cathodic biofilm dominated by Acetobacterium sp.Finally,three 3D printed cells were hydraulically connected in series to simulate an MES stack,achieving three-fold production rates than with the single cell at 0.25 mA cm^(−2).This confirms that three-chamber MES cells are an efficient and scalable technology for CO_(2)bio-electro recycling to acetate and that moderate saline conditions(5 g L^(−1)NaCl)can help reduce their power demand while preserving the activity of acetogens.
基金supported with funding from the Scottish Government Strategic Research Programme (2022-2027, C2-1 SRUC)Biotechnology and Biological Sciences Research Council (BBSRC) (BBS/E/C/000I0320 and BBS/E/C/000I0330)+1 种基金support from UKRI-BBSRC (UK Research and InnovationBiotechnology and Biological Sciences Research Council) via grants BBS/E/C/000I0320 and BBS/E/C/000I0330Rothamsted Research Science Initiative Catalyst Award supported by BBSRC。
文摘Agriculture is essential for providing food and maintaining food security while concurrently delivering multiple other ecosystem services. However,agricultural systems are generally a net source of greenhouse gases and ammonia. They, therefore, need to substantively contribute to climate change mitigation and net zero ambitions. It is widely acknowledged that there is a need to further reduce and mitigate emissions across sectors, including agriculture to address the climate emergency and emissions gap. This discussion paper outlines a collation of opinions from a range of experts within agricultural research and advisory roles following a greenhouse gas and ammonia emission mitigation workshop held in the UK in March 2022. The meeting identified the top mitigation priorities within the UK's agricultural sector to achieve reductions in greenhouse gases and ammonia that are compatible with policy targets. In addition, experts provided an overview of what they believe are the key knowledge gaps, future opportunities and cobenefits to mitigation practices as well as indicating the potential barriers to uptake for mitigation scenarios discussed.
