Interaction among multiple microorganisms and effects of nitrogen and carbon supplementations on lignin degradation

The mutual interactions among the consortium constructed by four indigenous bacteria and five inter-kingdom fusants and the effects of nitrogen and carbon supplementations on lignin degradation and laccase activity were investigated. Analyzed by Plackett–Burman and central composite design, the microbial consortium were optimized, Bacillus sp. (B) and PE-9 and Pseudomonas putida (Pp) and PE-9 had significant interactions on lignin degradation based on a 5% level of significance. The nitrogen and carbon supplementations played an important role in lignin degradation and laccase production. The ultimate lignin degradation efficiency of 96.0% and laccase activity of 268 U/L were obtained with 0.5 g/L of ammonium chloride and 2 g/L of sucrose. Results suggested that a stable and effective microbial consortium in alkalescent conditions was successfully achieved through the introduction of fusants, which was significant for its industrial application.