| Summary: | Trabajo presentado en el 7th International Congress on Biocatalysis, celebrado en Hamburgo (Alemania) del 31 de agosto al 04 de septiembre de 2014. The immobiliation of lipases on hydrophoic supports has been reported as a very effic1ent way to 1mmob.illze, punfy and hypract1vate the lipases, allowing to keep the open form of the enzyme wtthout any externa! interface [1]. This is based in the mechanism of interfacial activation of lipases during catalysis. A commercial and very hydrophobic styrene-divinylbenzene matrix, MCI GEL CHP20P (2,3], has been compared to octyl-Sepharose beads as support to immobilize tour different enzymes: lipases from Gandida antarctica (CALB), Thermomyces tanuginosus (TLL) and from Rhizomucor miehie (RML) and Lecitase Ultra, a commercial artificial phospholipase. The immobilization mechanism on both supports was similar: interfacial activation of the enzymes versus the hydrophobic surface of the supports. lmmobilization rate and loading capacity were much higher using the new support (around 110 mg CALB/wet g of support, 87.2 mg protein/g of support using TLL, 310 mg/g using RML and 180 mg/g using Lecitase Ultra). The thermal stabilities of ali new preparations were much lower than that of the standard octyl-Sepharose immobilized preparations, while the opposite occurs when the inactivations were performed in the presence of organic cosolvents . Regarding the hydrolytic activity, the results were quite surprising, with sorne substrates and under certain conditions one preparation could be sorne hundred folds more active that the other, while for other substrate and experimental condition, the opposite occurred. Thus, the immobilization of an enzyme on this matrix needs to be empirically evaluated, as in sorne cases may present very positive effects while in other cases may have very negative enes. Peer Reviewed
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