导电材料强化挥发性脂肪酸互营氧化产甲烷菌群的种间直接电子传递研究进展  

Direct interspecies electron transfer strengthened by conductive materials between syntrophic methanogenic communities of volatile fatty acids

作　　者：安彤 吴宗林 庞悦 孙照勇[1] 苟敏[1] AN Tong;WU Zonglin;PANG Yue;SUN Zhaoyong;GOU Min(Sichuan Provincial Key Laboratory for Resource Utilization of Organic Waste,College of Architecture and Environment,Sichuan University,Chengdu 610065,China)

机构地区：[1]四川大学建筑与环境学院,四川省环境保护有机废弃物资源化利用重点实验室,成都610065

出　　处：《应用与环境生物学报》2021年第3期800-807,共8页Chinese Journal of Applied and Environmental Biology

基　　金：科技部政府间国际科技创新合作重点专项(2016YFE0127700);成都市科技惠民计划项目(2016-HM01-00244-SF)资助。

摘　　要：挥发性脂肪酸(volatile fatty acid,VFA)降解是厌氧消化的限速步骤,其产甲烷效率取决于微生物的种间电子传递能力.种间直接电子传递(direct interspecies electron transfer,DIET)克服了种间氢/甲酸电子转移的热力学限制,可加速VFA降解产甲烷过程.基于微生物利用自身结构(如纳米导线、细胞色素c及其他蛋白组分等)进行DIET的原理,综述了外源添加导电材料对VFA厌氧消化产甲烷过程中DIET的强化效果及作用机制.碳材料和铁材料均能有效提高厌氧消化体系的甲烷产率,并缩短VFA的降解时间;碳材料通过替代纳米导线或富集具有DIET能力的微生物(如地杆菌)来实现DIET的强化.但不同类型铁材料的DIET强化机制存在着差异:磁铁矿的作用包括替代细胞色素c、诱导与DIET相关蛋白质的表达以及富集DIET微生物等;赤铁矿和针铁矿也可富集DIET微生物,此外赤铁矿还可促进细胞聚集体的形成及稳定,使DIET的进行更加有利.未来应进一步探究地杆菌以外微生物的DIET能力及作用机制,并优化导电材料强化厌氧消化产甲烷的工艺,以加速有机废弃物的高效资源化处理进程.The degradation of volatile fatty acids(VFAs)is the rate-limiting step of anaerobic digestion,and its methane production efficiency depends on interspecific electron transport.Direct interspecies electron transfer(DIET)can overcome the thermodynamic limitations of interspecies hydrogen/formate transfer and accelerate methane production via VFA degradation.Based on the principle that microorganisms use their own structures(such as nanowires,cytochrome c,and other protein components)to perform DIET,this article summarizes the strengthening effect and mechanism of DIET in the methanogenesis process of VFA anaerobic digestion by adding conductive materials.We showed that carbon and iron materials can effectively increase methane generation in anaerobic digestive systems and shorten the degradation time of VFA,and carbon materials can enhance DIET by replacing nanowires or enriching with microorganisms that are capable of DIET(e.g.,Geobacter).However,there are differences in the mechanism of DIET enhancement among different types of iron materials.The role of magnetite includes replacing cytochrome c,inducing the expression of proteins related to DIET,and enriching the microorganisms.Hematite and goethite can also enrich microorganisms related to DIET,and hematite can promote the formation and stabilization of aggregates,thereby supporting DIET.In the future,it is necessary to further explore the microorganisms that are capable of DIET other than Geobacter and optimize the process of anaerobic digestion with conductive materials to accelerate the efficiency and resource utilization processes of organic waste.

关 键 词：厌氧消化 挥发性脂肪酸 碳材料 铁材料 种间直接电子传递 

分 类 号：X705[环境科学与工程—环境工程]