Enhanced Productivity in Glycerol Carbonate Synthesis under Continuous Flow Conditions: Combination of Immobilized Lipases from Porcine Pancreas and Candida antarctica (CALB) on Epoxy Resins

Abstract

Among several value-added products from glycerol, glyceryl carbonate (GC) has gained prominence during the recent years because of its attractive physicochemical properties and the wide range of industrial applications. As a continuation of our efforts on GC production under environmentally benign conditions, in this work, we have applied a combination of two new biocatalysts containing lipases from porcine pancreas and Candida antarctica immobilized on epoxy resins for GC production via an integrated reaction between triacylglycerol and dimethyl carbonate under both batch and packed-bed reactors. Under continuous flow conditions, the 1:1 (w/w) combination of the home-made immobilized biocatalysts was able to lead to complete conversion of GC with >99% selectivity against 88% demonstrated by the commercial preparation Novozym 435. The new continuous flow biocatalytic system demonstrated a final productivity of 16 × 10 −2 g of GC/h/U of the biocatalyst.

Regioselective Acylation of Levoglucosan Catalyzed by Candida Antarctica (CaLB) Lipase Immobilized on Epoxy Resin

“…The home-made CaLB_epoxy biocatalyst contains CaLB immobilized by hydrophobic adsorption on epoxiresin Purolite®ECR 82057, with hydrolysis activity of 419 U/g. Previous work of our group [13][14][15]. demonstrated that this derivative also showed higher esterification potential than N435 with a protein load of 11 mg/g of support against 15 mg/g of support presented by N435.…”

“…Once the structure of compounds 1 and 2 is determined, it can be established what compound is formed in the transesterification reaction. Table 2 shows the 1 H NMR chemical shifts (ν, ppm) and coupling constants (J HH , Hz), and 13 C chemical shifts (ν, ppm) for compounds 1 and 2. In order to verify the regioselectivity of the reaction studied, regioisomers were isolated and characterized by ¹H NMR, 13 C NMR, NOEDIFF, and Infrared (FTIR) techniques (see Support Information).…”

“…Table 2 shows the 1 H NMR chemical shifts (ν, ppm) and coupling constants (J HH , Hz), and 13 C chemical shifts (ν, ppm) for compounds 1 and 2. In order to verify the regioselectivity of the reaction studied, regioisomers were isolated and characterized by ¹H NMR, 13 C NMR, NOEDIFF, and Infrared (FTIR) techniques (see Support Information). In order to unequivocally determine the structure of compounds 1 and 2, 2D NMR (HMBC and HSQC) experiments were carried out.…”

“…Among the several enzymes that are currently applied in biocatalysis, lipases (triacylglycerol ester hydrolases E.C. 3.1.1.3) [13] have been outstanding for their great industrial application in the production of high added value esters due to, among other advantages, their ability to show activity both of hydrolysis and esterification, the non-requirement of cofactors, and their ability to be able to perform reactions with high regio-, enantio-, and chemo-selectivity. Lipase-catalyzed transformations play an important role in organic synthesis to fulfill the rapidly growing demand for enantiomerically pure compounds such as pharmaceuticals, agrochemicals, and natural products, mainly due to no requirement for cofactors and also the capacity of catalyzing different reactions such as asymmetric esterification, asymmetric transesterification, and asymmetric hydrolysis.…”

“…Lipase immobilization is an effective method to improve the performance of free enzymes. Compared with free enzymes, the immobilized enzymes with long-term operational stability can be easily recovered and reutilized, thus reducing the costs of catalytic processes [13]. The activity of the immobilized lipases depends on some parameters such as enzyme and support types and the protocols of immobilization.…”