Enhancement of an efficient enzyme cocktail from Penicillium consortium on biodegradation of pretreated poplar

•Penicillium consortium-derived enzyme mixtures could enhance the hydrolysis.•Addition of LPMOs producing strains enriched the enzymatic synergy.•Structure-effect relationship was investigated on basis of pretreated poplar as substrate.•The optimized enzyme formulation strategy achieved hydrolysis yield of 88.7%.•Transcriptome profiling of CAZymes was studied to evaluate the enzyme system.