Enhanced recovery of lipase derived from Burkholderia cepacia from fermentation broth using recyclable ionic liquid/polymer-based aqueous two-phase systems

In this work, a microbial lipase recovery scheme based on aqueous two-phase systems (ATPS) formed by a biocompatible ionic liquid (IL) and a thermo-sensitive polymer was studied. The IL composed of naturally derived cholinium cation and anion obtained from biological buffer, i.e. BES, designated as [Ch][BES], was used to prepare ATPS with polypropylene glycol with an average molecular weight of 400 g mol−1 (PPG 400). In conjugation with centrifugation step as pre-purification, the IL/polymer-based ATPS achieved an enhanced recovery of lipase from fermentation broth with a purification factor of 17.96 ± 0.32 and a recovery yield of 99.30% ± 0.03, after evaluating several phase compositions and feedstock loads. The recycling use of both phase-forming components was investigated, and there was no significant difference in the purification results with the use of recycled components compared to the systems using fresh chemicals. The proposed system is associated with many advantageous properties such as fast, simple, high biocompatibility, marginally toxicity, non-volatility, buffering capacity and recyclability, supporting its potential as a viable and sustainable platform for lipase purification.