These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


Pubmed for Handhelds

PUBMED FOR HANDHELDS

Search MEDLINE/PubMed

  • Title: Kinetics and thermodynamics of the thermal inactivation of polyphenol oxidase in an aqueous extract from Agaricus bisporus.
    Author: Gouzi H, Depagne C, Coradin T.
    Journal: J Agric Food Chem; 2012 Jan 11; 60(1):500-6. PubMed ID: 22148350.
    Abstract:
    The kinetics and thermodynamics of the thermal inactivation of polyphenol oxidase (PPO) in an aqueous extract from mushroom Agaricus bisporus (J.E. Lange) Imbach was studied, using pyrocatechol as a substrate. Optimal conditions for enzymatic studies were determined to be pH 7.0 and 35-40 °C. The kinetics of PPO-catalyzed oxidation of pyrocatechol followed the Haldane model with an optimum substrate concentration of 20 mM. Thermal inactivation of PPO was examined in more detail between 50 and 73 °C and in relation to exposure time. Obtained monophasic kinetics were adequately described by a first-order model, with significant inactivation occurring with increasing temperature (less than 10% preserved activity after 6 min at 65 °C). Arrhenius plot determination and calculated thermodynamic parameters suggest that the PPO in aqueous extract from Agaricus bisporus mushroom is a structurally robust yet temperature-sensitive biocatalyst whose inactivation process is mainly entropy-driven.
    [Abstract] [Full Text] [Related] [New Search]