摘要
Deep eutectic solvents were screened for efficient bromelain extraction. • DESs effectively disrupted the recalcitrance of cell wall by selectively removing lignin. • The extraction mechanism was owing to reconstruction of hydrogen bonding network between lignin and ChCl:Gly. • The stability mechanism was verified by molecular docking and inactivation kinetics. • In situ ChCl:Gly/salt ATPS was formed for the efficient purification of bromelain. To make full utilization of pineapple peel, which is usually discarded as pineapple processing waste, deep eutectic solvents (DESs) were screened to disrupt cell wall for the extraction of bromelain, and then in situ DES/salt aqueous two-phase system was constructed for the efficient purification of bromelain. The degree of cell wall disruption was tuned effectively by adjusting the interactions between DESs and cell wall components. ChCl:Gly reconstructed the hydrogen bonding network between lignin and itself to selectively remove lignin in compound middle lamella and cell corners, and retain hemicellulose and cellulose, which gave high extraction yield (6.4 mg/g), high activity (88.7 U/mg) and high purity under the optimum conditions. The unique hydrogen bonding environment constructed by ChCl:Gly maintained the conformation and enhanced the stability of bromelain. The crude extracts containing ChCl:Gly was further subjected to aqueous two-phase system to obtain the purified bromelain, where extraction efficiency of 96% with activity recovery of 111% and 2.58-fold purification was achieved. More importantly, ChCl:Gly exhibited the capacity for multiple recycling and reuse cycles with stable extraction efficiency, activity recovery and purification fold. The proposed platform integrates extraction, purification and enrichment in one step, achieving green and sustainable extraction of high-yield and high-purity bromelain from pineapple peel Download: Download high-res image (357KB) Download: Download full-size image
危险品化学品经营许可证（带存储）