Mono- and heterofunctionalized silica magnetic microparticles (SMMPs) as new carriers for immobilization of lipases

Abstract

a b s t r a c tIn order to improve economic viability of an enzymatic process, the use of an operationally stable and low-cost biocatalyst is encouraged. Although the immobilization of lipases is widely reported, the search for new supports and immobilization protocols with better properties is still important. In this study, mono-and heterofunctionalized silica magnetic microparticles (SMMPs) were synthetized for immobilization of lipase B from Candida antarctica (CALB). The SMMPs were prepared in a micro-emulsion system containing sodium silicate and superparamagnetic iron oxide nanoparticles, followed by chemical modification with octyl groups and octyl plus aldehyde groups. These supports allowed the immobilization of CALB by hydrophobic adsorption or hydrophobic/covalent linkages, achieving immobilization yield of 88% and recovered activities of 128% and 59%, respectively. The performance of the magnetic biocatalysts was evaluated in the synthesis of xylose fatty acid esters (laurate or oleate) in tert-butyl alcohol medium, yielding around 60% conversion after 48 h under optimized conditions (xylose/fatty acid molar ratio of 1:0.2, 55 • C, and activity load of 37.5 U/g). The magnetic biocatalyst was used in 10 reaction cycles of 48 h at 46 • C maintaining high xylose conversions. Besides, the biocatalyst might be easily and quickly recovered from the reaction medium by an external magnetic field, an operational advantage in the case of viscous and complex media, e.g., medium containing insoluble sugars and molecular sieves.

Lipozyme 435-Mediated Synthesis of Xylose Oleate in Methyl Ethyl Ketone

“…Some studies already evaluated the use of molecular sieves in the enzyme-catalyzed synthesis of xylose fatty esters [ 6 , 12 , 27 , 56 ]. Among those authors, Tsukamoto et al [ 56 ] found higher xylose conversions in the presence of MS when compared to the conversions in the absence of them.…”

“…The interfacial adsorption of lipases on hydrophobic supports [ 24 ], covalent bonds, and ionic interactions are among the immobilization techniques reported in this period [ 25 ]. These methods included the use of different supports, such as chitosan, celite, silica magnetic microparticles, octyl silica [ 26 , 27 , 28 , 29 ], and microemulsion-based organogels (MBGs) [ 30 , 31 ].…”

Synthesis, characterization and application of lipase-conjugated citric acid-coated magnetic nanoparticles for ester synthesis using waste frying oil

“…Similarly, immobilized Pseudomonas cepacia lipase onto magnetic nanoparticles (MNPs) was used for ester production from waste cooking oil. Lipase from Rhizomucor miehei immobilized on ion-exchange macroporus hydrophilic resins also used for trans-esterification of waste oil for ester production (de Lima et al 2016).…”

1,3‐Regiospecific ethanolysis of soybean oil catalyzed by crosslinked porcine pancreas lipase aggregates

“…3.1.1.3) are enzymes whose physiological function is the hydrolysis of triacylglycerols, while in vitro they may be used in the reverse reaction (esterification), as well as transesterification . They are an important group of biocatalysts, with biotechnological applications in many biotransformation reactions in the pharmaceutical, food, and agrochemical industries due to their excellent chemo‐, regio‐ and enantio‐specificities . These enzymes have a peculiar mechanism of catalysis, denominated interfacial activation that permits them to fulfill their physiological function …”

“…[12][13][14] They are an important group of biocatalysts, with biotechnological applications in many biotransformation reactions in the pharmaceutical, food, and agrochemical industries due to their excellent chemo-, regio-and enantio-specificities. [15][16][17][18][19][20] These Correspondence concerning this article should be addressed to P.W. Tardioli at pwtardioli@ufscar.br and to W. Kopp at solutions@kopptechnologies.com or willkopp@gmail.com enzymes have a peculiar mechanism of catalysis, denominated interfacial activation that permits them to fulfill their physiological function.…”