The properties of digestates generated through anaerobic digestion are influenced by interactions between the digester microbial communities, feedstock properties and digester operating conditions. This study investigated the effect of varying initial feedstock carbon to nitrogen (C/N) ratios on digestate microbiota and predicted abundance of genes encoding lignocellulolytic activity. The C/N ratio had a significant impact on the digestate microbiome. Feedstocks with intermediate C/N ratio (20–27) (where higher biomethane potential was observed) showed higher relative abundance of archaea compared to feedstocks with C/N ratios at 17 and 34. Within microbial networks, four microbial clusters and eight connector microorganisms changed significantly with the C/N ratio (P < 0.05). Feedstocks with C/N < 23 were richer in organisms from the family Thermotogaceae and genus Caldicoprobacter and enhanced potential for degradation of maltose, galactomannans, melobiose and lactose. This study provides new insights into how anaerobic digestion conditions relate to the structure and functional potential of digester microbial communities, which may be relevant to both digester performance and subsequent utilization of digestates for composting or amending soil.

通过厌氧消化产生的消化物的特性受到消化器微生物群落，原料特性和消化器操作条件之间相互作用的影响。这项研究调查了变化的初始原料碳氮比（C / N）对消化微生物群的影响，并预测了编码木质纤维素分解活性的基因的丰度。C / N比对消化微生物组有重要影响。与C / N比为17和34的原料相比，C / N比为中间值（20-27）（观察到更高的生物甲烷潜力）的古菌的相对丰度更高。在微生物网络中，有四个微生物簇和八个连接微生物随C / N比的变化显着（P <0.05）。C / N <23的原料富含嗜热热菌科和Caldicoprobacter属的生物，并且具有降解麦芽糖，半乳甘露聚糖，美洛糖和乳糖的潜力。这项研究为厌氧消化条件与消化池微生物群落的结构和功能潜力之间的关系提供了新的见解，这可能与消化池的性能以及随后用于消化堆肥或改良土壤的消化池的利用率有关。