Pomegranate peels are an abundant agricultural waste material with a high content of carbohydrates and bioactive compounds. The aim of this study was to efficiently convert waste pomegranate peels (WPP) into high-value-added products. First, high yields of phenolics (12.2%) and bioactive pectin (24.8%) were obtained via enzymatic pretreatment. The lignin was subsequently degraded using an integrated method combining heteropolyacids as catalyst and biomass-derived gamma-valerolactone as sustainable solvent and cellulase-catalyzed hydrolysis. The optimal degradation conditions were found to encompass a temperature of 293K, reaction time of 3h and catalyst loading with 30mM heteropolyacids. Under these conditions, the enzymatic hydrolysis efficiency was enhanced significantly, leading to a yield of 93.3% glucose from the obtained cellulosic feedstock. Finally, the fermentable sugars together with the previously recovered pectin from WPP were firstly used as carbon source to evaluate their suitability as feedstock for butyric acid production using Clostridium tyrobutyricum.