Extracting extremophilic lipases from aqueous streams by using biocompatible ionic liquids
DATE:
2022-11
UNIVERSAL IDENTIFIER: http://hdl.handle.net/11093/4130
EDITED VERSION: https://linkinghub.elsevier.com/retrieve/pii/S0167732222017536
DOCUMENT TYPE: article
ABSTRACT
In this work, biocompatible ionic liquids based on aminoacids were employed as extractants to separate
extremolipases from aqueous streams. First, the influence of aminoacid and dipeptide-based ionic liquids
(cholinium glycinate, ChGly, and cholinium glycylglycinate, ChGlygly) on the lipolytic activity of a commercial
lipase from Candida antarctica (CaLB) and in-house synthesized extremophilic lipases from
Thermus thermophilus HB27 (TtHB27L) and Halomonas sp. LM1C (HL) was investigated. The combination
of thermophilic enzyme with ChGly turned out to be the optimum combination for maximizing the biocatalytic
performance, clearly improving the levels attained when water was exclusively employed as
solvent and also surpassing the activity levels provided for the commercial enzyme CaLB. The salting
out capacity of ChGly in aqueous solutions of biodegradable surfactants Tergitol 15S7 and Tergitol
15S9 was discussed, recording immiscibility areas almost covering all the ternary diagrams. The aqueous
biphasic systems were experimentally characterized by determining both tie-lines and solubility curves
at several temperatures and the data was modelled with relevant equations like Merchuk, Othmer-Tobias
and Bancroft ones, as they are the most common ones to describe this kind of equilibrium data. So, ChGly
was applied to extract thermophilic and commercial lipases from aqueous solutions at 313.15 K, achieving
very high extraction levels (about 100 %) for TtHB27L, which clearly surpasses the maximum extraction
values observed for the commercial enzyme (about 80 %). Finally, the process was simulated at real
scale through SuperPro Designer v.8.5 for the production of 385 Kg/year of extremolipase