Fine-tuning the second generation sol–gel lipase immobilization with ternary alkoxysilane precursor systems

From Synthetic Chemistry and Stereoselective Biotransformations to Enzyme Biochemistry – The Bioorganic Chemistry Group at the Budapest University of Technology and Economics

“…The sol-gel encapsulated enzymes usually retain their selectivity whereas their heat stability or specific activity may be significantly improved. BCG researchers investigated the lipase immobilization by entrapment in sol-gel matrices to study the effect of enzymes, supports, enzyme/ support ratios, silane precursor composition and bioimprinting effect of additives [43][44][45][46][47]. In addition to test the resulting solgel lipases in kinetic resolution of 1-phenylethanol 1j using batch mode [43][44][45][46][47], the reactions were studied in continuousflow systems as well [41].…”

Electrospun polylactic acid and polyvinyl alcohol fibers as efficient and stable nanomaterials for immobilization of lipases

“…Effective specific activity of the crude non-immobilized enzyme powder (U E ) was determined using the equation U E = (n rac 9 c)/(t 9 m E ) [where n rac (lmol) is the amount of the racemic substrate, t (min) is the reaction time and m E (g) is the mass of the crude nonimmobilized enzyme powder] [29]. The activity yield [Y A (%)] can be calculated from the effective specific activity of the immobilized biocatalyst (U B ) compared to the effective specific activity of the non-immobilized enzyme (U E ) using the equation Y A = 100 9 U B /U E which is equal to the equation Y A = 100 9 [(n rac 9 c)/(t 9 m B )]/U E [29].…”

Applications of Ionic Liquids to Increase the Efficiency of Lipase Biocatalysis

“…Recently, ternary silane mixtures, containing alkyl-triethoxysilanes, phenyl-triethoxysilane and tetraethoxysilane, have been reported with higher catalytic efficiency than the corresponding binary silane mixtures, for the sol-gel entrapment of Celite-supported Pseudomonas fluorescens lipase (Tomin et al, 2010). Based on these results, we used in the immobilization protocol binary and ternary mixtures of methyl-trimethoxysilane (MTMOS), phenyl-trimethoxysilane (PhTMOS), and tetramethoxysilane (TMOS), as well as [Emim]BF 4 or [Omim]BF 4 as additive.…”

“…Conducting the sol-gel process in the presence of a biomolecule will result in its entrapment by the obtained matrix (Pierre, 2004). Lipase immobilization by the sol-gel method was subject of numerous recent publications (Kiss et al, 2007;Hara et al, 2008;Kawakami et al, 2009;Tomin et al, 2010). The main benefit of this method is the enzyme inclusion throughout the gelation phase, at low synthesis temperature and not adverse reaction medium for the catalytic activity (Ciriminna & Pagliano, 2006).…”