Enhanced turnover of phenolic precursors by Gloeophyllum trabeum pretreatment promotes humic substance formation during co-composting of pig manure and wheat straw

Abstract The present work aimed to explore the effect of Gloeophyllum trabeum pretreatment on phenol dynamics, humic substance (HS) formation and bacterial community succession during co-composting of wheat straw (WS) and pig manure (PM). The results showed that the phenol production was significantly improved during WS pretreatment with G. trabeum. Moreover, the phenol conversion during composting was significantly promoted after G. trabeum pretreatment of WS. Compared with raw WS, the composting process was accelerated by 13 days and HS content was increased by 15.7% during co-composting of pretreated WS and PM. Furthermore, G. trabeum pretreatment increased the relative content of aromatic functional groups in HS by enhancing the correlations between phenolic compounds and chemical structure of HS. The influence of phenol on bacterial community shift was strengthened by G. trabeum pretreatment, resulting in increased relative abundance of laccase-producing bacteria. Our findings provide a new way to promote the humification process by enhancing phenolic precursors turnover with functional microorganisms.