Abendroth Christian, Vilanova Cristina, Günther Thomas, Luschnig Olaf, Porcar Manuel
Cavanilles Institute of Biodiversity and Evolutionary Biology, Universitat de València, 46020 Valencia, Spain ; Bio H2 Energy GmbH, Im Steinfeld 10, 07751 Jena, Germany.
Cavanilles Institute of Biodiversity and Evolutionary Biology, Universitat de València, 46020 Valencia, Spain.
Biotechnol Biofuels. 2015 Jun 18;8:87. doi: 10.1186/s13068-015-0271-6. eCollection 2015.
Only a fraction of the microbial species used for anaerobic digestion in biogas production plants are methanogenic archaea. We have analyzed the taxonomic profiles of eubacteria and archaea, a set of chemical key parameters, and biogas production in samples from nine production plants in seven facilities in Thuringia, Germany, including co-digesters, leach-bed, and sewage sludge treatment plants. Reactors were sampled twice, at a 1-week interval, and three biological replicates were taken in each case.
A complex taxonomic composition was found for both eubacteria and archaea, both of which strongly correlated with digester type. Plant-degrading Firmicutes as well as Bacteroidetes dominated eubacteria profiles in high biogas-producing co-digesters; whereas Bacteroidetes and Spirochaetes were the major phyla in leach-bed and sewage sludge digesters. Methanoculleus was the dominant archaea genus in co-digesters, whereas Methanosarcina and Methanosaeta were the most abundant methanogens in leachate from leach-bed and sewage sludge digesters, respectively.
This is one of the most comprehensive characterizations of the microbial communities of biogas-producing facilities. Bacterial profiles exhibited very low variation within replicates, including those of semi-solid samples; and, in general, low variation in time. However, facility type correlated closely with the bacterial profile: each of the three reactor types exhibited a characteristic eubacteria and archaea profile. Digesters operated with solid feedstock, and high biogas production correlated with abundance of plant degraders (Firmicutes) and biofilm-forming methanogens (Methanoculleus spp.). By contrast, low biogas-producing sewage sludge treatment digesters correlated with high titers of volatile fatty acid-adapted Methanosaeta spp.
在沼气生产厂用于厌氧消化的微生物物种中，只有一小部分是产甲烷古菌。我们分析了德国图林根州七个设施中九个生产厂（包括共消化器、渗滤床和污水污泥处理厂）样本中的真细菌和古菌的分类学概况、一组化学关键参数以及沼气产量。对反应器进行了两次采样，间隔为1周，每次采样均采集三个生物学重复样本。
发现真细菌和古菌的分类组成都很复杂，且二者都与消化器类型密切相关。在高产沼气的共消化器中，降解植物的厚壁菌门以及拟杆菌门在真细菌概况中占主导；而拟杆菌门和螺旋体门是渗滤床和污水污泥消化器中的主要门类。甲烷袋状菌属是共消化器中的优势古菌属，而甲烷八叠球菌属和甲烷鬃菌属分别是渗滤床和污水污泥消化器渗滤液中最丰富的产甲烷菌。
这是对沼气生产设施微生物群落最全面的表征之一。细菌概况在重复样本中，包括半固体样本中，变化非常小；总体而言，随时间变化也很小。然而，设施类型与细菌概况密切相关：三种反应器类型中的每一种都呈现出独特的真细菌和古菌概况。使用固体原料运行的消化器以及高产沼气与植物降解菌（厚壁菌门）和形成生物膜的产甲烷菌（甲烷袋状菌属物种）的丰度相关。相比之下，低产沼气的污水污泥处理消化器与适应挥发性脂肪酸的甲烷鬃菌属的高滴度相关。
