Artículos de revistas
Characterisation of 'Starking' apple polyphenoloxidase
Registro en:
Journal Of The Science Of Food And Agriculture. John Wiley & Sons Ltd, v. 77, n. 4, n. 527, n. 534, 1998.
0022-5142
WOS:000075619500017
10.1002/(SICI)1097-0010(199808)77:4<527
Autor
Rocha, AMCN
Cano, MP
Galeazzi, MAM
Morais, AMMB
Institución
Resumen
Experiments were performed to optimise the extraction conditions of 'Starking' apple fruit polyphenoloxidase (PPO), to evaluate the affinity and specificity towards several substrates and to study the stability of enzyme extracts from apple samples stored under different conditions. Sodium phosphate buffer (0.2 M, pH 6.5) plus 0.25% Triton X-100 and 1% or 2% PVPP was found to be the most efficient extraction medium. Chlorogenic acid, dopamine and 4-methylcatechol showed similar specificity towards PPO, and chlorogenic acid was found to be the best substrate for the enzyme. Enzyme extracts from frozen cut apple stored at -4 degrees C, and extracts from lyophilised apple samples stored at 4 degrees C were more stable than extracts obtained from fresh-cut or acetone powder samples. (C) 1998 SCI. 77 4 527 534