RT info:eu-repo/semantics/article T1 Enzymatic activity and conformational and morphological studies of four commercial lipases treated with supercritical carbon dioxide A1 Melgosa Gómez, Rodrigo A1 Sanz Díez, Mª Teresa A1 García Solaesa, Ángela A1 Bucio López, Silvia Liliana A1 Beltrán Calvo, Sagrario K1 Candida antarctica lipase B K1 Rhizomucor miehei lipase K1 Immobilized lipase K1 Lipozyme K1 Enzyme activity K1 Supercritical carbon dioxide K1 Chemical engineering K1 Ingeniería química AB This work investigates the effect of supercritical carbon dioxide (SC-CO2) treatment on four commer-cial lipases. The influence of experimental conditions: temperature (35–70◦C), pressure (10–25 MPa),exposure time (1–3 h) and depressurization steps (1–3) on the residual activity was studied. Activityenhancement was verified for free enzymes (Palatase 20000 L and Lipozyme CALB L) treated at mildconditions; while the highest temperature and pressure and the longest exposure time assayed led toactivity losses. On the other hand, activity losses or no significative effect of the treatment in the enzymeactivity were observed on immobilized enzymes (Lipozyme RM IM and Lipozyme 435). Qualitative stud-ies were also performed: Fluorescence emission spectra showed changes in the conformational structureof both two free enzymes after SC-CO2treatment. Scanning electron micrographs showed morphologicalalterations in the immobilization supports of the treated enzymes; while infrared spectra did not showchemical modifications. PB Elsevier SN 0896-8446 YR 2015 FD 2015-02 LK http://hdl.handle.net/10259/4339 UL http://hdl.handle.net/10259/4339 LA eng NO (MINECO) and the EuropeanRegional Development Fund (ERDF) for financial support to theproject CTQ2012-39131-C02-01. DS Repositorio Institucional de la Universidad de Burgos RD 24-dic-2024