Anaerobic oxidation of methane(AOM)can contribute to reducing methane emissions in landfills;however,the AOM rates vary depending on the inoculum source.This study addressed the capacity of AOM of a fermentative micro...Anaerobic oxidation of methane(AOM)can contribute to reducing methane emissions in landfills;however,the AOM rates vary depending on the inoculum source.This study addressed the capacity of AOM of a fermentative microbial community derived from a reactor treatingmunicipal solidwastes.First,the inoculum’s autotrophic capacitywas verified using a gasmixture of 75% CO_(2) and 25% H_(2).Results demonstrated that the fermentative microbial community reached amaximum CO_(2) consumption rate of 22.5±1.2 g CO_(2)/(m^(3)·h),obtaining acetate as the main product.Then,the inoculum was grown on a gas mixture of 50%CH_(4),35%CO_(2),and 15%N_(2),using iron(Fe^(3+))as the electron acceptor.The AOM rates increased over time and peaked at 3.1±0.9 g CH_(4)/(m^(3)·h)by 456 h with the simultaneous consumption of CO_(2).Acetate was the main product,with amaximum concentration of 180±9mg/L.By 408 h,a bacterial cluster of indicator species correlated with the AOM rates,including to Rhodobactereceae(r=0.80),Oceanicola(r=0.80),Propionicicella(r=0.77),Christensenellaceae(r=0.58),Oscillospiraceae(r=0.53),Mobilitalea(r=0.66),Hungateiclostridiaceae(r=0.46),and Izemoplasmatales(r=0.77).Methanosarcina,Methanobacterium,and Methanoculleus correlated with the AOM and CO_(2) consumption rates.A co-occurrence network analysis showed that Methanosarcina positively interacted with syntrophic bacteria like Christensenellaceae and Acinetobacter and diverse heterotrophic bacteria.This study demonstrated the feasibility of obtaining a CH_(4)-oxidizing microbial community in 16 days,exhibiting AOM rates higher than those reported for soils.展开更多
基金This work was supported by the DGAPA-UNAM(PAPIIT project,No.IN102721)the support from CONAHCYT through the Investigadoras e Investigadores por Mexico program(Researcher ID 6407,Project 265).
文摘Anaerobic oxidation of methane(AOM)can contribute to reducing methane emissions in landfills;however,the AOM rates vary depending on the inoculum source.This study addressed the capacity of AOM of a fermentative microbial community derived from a reactor treatingmunicipal solidwastes.First,the inoculum’s autotrophic capacitywas verified using a gasmixture of 75% CO_(2) and 25% H_(2).Results demonstrated that the fermentative microbial community reached amaximum CO_(2) consumption rate of 22.5±1.2 g CO_(2)/(m^(3)·h),obtaining acetate as the main product.Then,the inoculum was grown on a gas mixture of 50%CH_(4),35%CO_(2),and 15%N_(2),using iron(Fe^(3+))as the electron acceptor.The AOM rates increased over time and peaked at 3.1±0.9 g CH_(4)/(m^(3)·h)by 456 h with the simultaneous consumption of CO_(2).Acetate was the main product,with amaximum concentration of 180±9mg/L.By 408 h,a bacterial cluster of indicator species correlated with the AOM rates,including to Rhodobactereceae(r=0.80),Oceanicola(r=0.80),Propionicicella(r=0.77),Christensenellaceae(r=0.58),Oscillospiraceae(r=0.53),Mobilitalea(r=0.66),Hungateiclostridiaceae(r=0.46),and Izemoplasmatales(r=0.77).Methanosarcina,Methanobacterium,and Methanoculleus correlated with the AOM and CO_(2) consumption rates.A co-occurrence network analysis showed that Methanosarcina positively interacted with syntrophic bacteria like Christensenellaceae and Acinetobacter and diverse heterotrophic bacteria.This study demonstrated the feasibility of obtaining a CH_(4)-oxidizing microbial community in 16 days,exhibiting AOM rates higher than those reported for soils.
