About the role of typical spacer/crosslinker on the design of efficient magnetic biocatalysts based on nanosized magnetite

Immobilization of lipases on hydrophobic supports: immobilization mechanism, advantages, problems, and solutions

“…Using Novozym 435, this desorption problem was reported long time ago using clearly amphipathic molecules (Hilterhaus et al, 2008;Nicolás et al, 2015;Ortiz et al, 2019). It must be considered that in many cases lipases will be used to modify triglycerides, and that free fatty acids, di or monoglycerides and phospholipids, may be considered molecules with detergent properties able to release the lipase from hydrophobic supports (Hilterhaus et al, 2008;Nicolás et al, 2015;Ortiz et al, 2019). Moreover, it has been recently shown that this effect may be found even using relatively small products, such as high concentrations of dibutyrin or even diacetin (Hirata et al, 2016b, 2016a; Virgen-Ortíz et al, 2017c) ( Figure 9).…”

“…protocol. However, this immobilization protocol has a significant problem: the enzyme may be released to the medium under certain conditions, producing both biocatalyst operational inactivation and product contamination (Chen et al, 2007(Chen et al, , 2008Garcia-Galan et al, 2011;Hilterhaus et al, 2008;Kirk and Christensen, 2002;Nicolás et al, 2015;Petry et al, 2006;Saunders and Brask, 2010;Weinberger et al, 2018).…”

“…Another additional problem of this immobilization technique is when the use of the biocatalysts involves detergent-like substrates or products (Virgen-Ortíz et al, 2017c) ( Figure 9). Using Novozym 435, this desorption problem was reported long time ago using clearly amphipathic molecules (Hilterhaus et al, 2008;Nicolás et al, 2015;Ortiz et al, 2019). It must be considered that in many cases lipases will be used to modify triglycerides, and that free fatty acids, di or monoglycerides and phospholipids, may be considered molecules with detergent properties able to release the lipase from hydrophobic supports (Hilterhaus et al, 2008;Nicolás et al, 2015;Ortiz et al, 2019).…”

Novozym 435: the “perfect” lipase immobilized biocatalyst?

“…496 Enzyme release from N435 was also reported in the solvent-free esterification of polyglycerol-3 and related compounds, due to their surfactant features. 491 Enzyme release even in its first use has been reported in oil chemistry 497 and polymer production. 383 Enzyme release from N435 in organic solvents and ionic liquids has been also reported to be a real problem, as "active" traces of the active material were released from the catalyst and hindered the control of the reaction (because some reactions continued after eliminating N435) 498,499 Thus, this enzyme release has been in fact considered as one of the main problems for the industrial implementation of N435.…”

Influence of the nature of the support on the catalytic performance of CALB: experimental and theoretical evidence

“…35 The magnetic support used in this contribution was composed by chitosan crosslinked to nanosized Fe 3 O 4 with glutaraldehyde and further functionalized with 3-aminopropyl-triethoxisilane APTS. 21 In this particular case, the lipase is immobilized to the support through adsorption (on the APTS, the surface of Figure 1A). In general, the conversion reaches 60 % with the exception of CALB/PPL.…”