RT info:eu-repo/semantics/article T1 Studies of polyphenol oxidase inactivation by means of high pressure carbon dioxide (HPCD) A1 Benito Román, Oscar A1 Sanz Díez, Mª Teresa A1 Melgosa Gómez, Rodrigo A1 Paz Barragán, Esther de A1 Escudero Barbero, Isabel A1 Beltrán Calvo, Sagrario K1 Polyphenol oxidase K1 HPCD K1 Enzyme inactivation K1 Supercritical carbon dioxide K1 Ingeniería química K1 Chemical engineering AB Tyrosinase from mushroom was used as a model polyphenol oxidase (PPO) enzyme to perform a systematic inactivation study using High Pressure Carbon Dioxide (HPCD). The ratio CO2/volume of enzyme (g/mL) loaded in the reactor was found to be critical. Above a critical ratio, pressure, temperature and time did not control the inactivation performance. Exposure time (2–15 min), temperature (25–45 °C) and pressure (5–20 MPa) allowed to show a characteristic inactivation pattern for PPO: a sudden decrease in activity (at least 75% of the total activity loss was observed within the first 2 min) was followed by a slowed decay. The experimental data were fitted into a two fraction kinetic model and the main kinetic parameters (ZP, ZT activation volume and activation energy) were calculated. The fluorescence spectroscopy analysis of the samples treated with HPCD revealed significant changes in the tertiary structure of the enzyme. PB Elsevier SN 0896-8446 YR 2019 FD 2019-05 LK http://hdl.handle.net/10259/5076 UL http://hdl.handle.net/10259/5076 LA eng NO Spanish Government (MINECO) and the European Regional Development Fund (ERDF) for financial support of project CTQ2015-64396-R (MINECO/FEDER, UE). To Junta de Castilla y León and ERDF for O.Benito’s Post-doctoral contract funded by project BU055U16. To MINECO for E. de Paz’s Juan de la Cierva Contract (FJCI-2014-19850). DS Repositorio Institucional de la Universidad de Burgos RD 24-nov-2024