HSQC (heteronuclear single quantum coherence) 13C-1H correlation spectra of whole biomass in perdeuterated pyridinium chloride-DMSO system: An effective tool for evaluating pretreatment

► Poplar was subjected to steam, lime and dilute acid pretreatments. ► Perdeuterated pyridiniumchloride-DMSO-d6 used for biomass dissolution followed by HSQC NMR analysis. ► HSQC analysis estimated steam pretreatment significant lignin and hemicellulose degradation occurred. ► Lime pretreatment resulted mainly hemicelluloses dissolution and selective PB lignin degradation. ► Dilute sulfuric acid pretreatment completely removed the hemicelluloses and harsh lignin degradation.