2026-04-28T21:06:13Zhttps://riubu.ubu.es/oai/request

oai:riubu.ubu.es:10259/43392022-12-19T11:00:07Zcom_10259_4244com_10259_5086com_10259_2604col_10259_4245

2017-02-13T11:17:22Z urn:hdl:10259/4339 Enzymatic activity and conformational and morphological studies of four commercial lipases treated with supercritical carbon dioxide Melgosa Gómez, Rodrigo Sanz Díez, Mª Teresa García Solaesa, Ángela Bucio López, Silvia Liliana Beltrán Calvo, Sagrario Candida antarctica lipase B Rhizomucor miehei lipase Immobilized lipase Lipozyme Enzyme activity Supercritical carbon dioxide 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. 2017-02-13T11:17:22Z 2017-02-13T11:17:22Z 2015-02 info:eu-repo/semantics/article 0896-8446 http://hdl.handle.net/10259/4339 eng The Journal of Supercritical Fluids. 2015, V. 97, p. 51–62 http://dx.doi.org/10.1016/j.supflu.2014.11.003 http://creativecommons.org/licenses/by-nc-nd/4.0/ info:eu-repo/semantics/openAccess Attribution-NonCommercial-NoDerivatives 4.0 International Elsevier