Characterisation of 'Starking' apple polyphenoloxidase

• Type: Article in International Scientific Journal
• Date: 1998

Authors

Rocha, Ada (Author) FCNAUP; Cano, MP (Author) Other; Galeazzi, MAM (Author) Other; Morais, AMMB (Author) Other

Journal

Title: Journal of the Science of Food and Agriculture

Vol. 77 No. 4

Pages: 527-534

ISSN: 0022-5142

Publisher: Wiley-Blackwell

Indexing

ISI Web of Knowledge - 36 Citations

Scopus - 37 Citations

Scientific classification

FOS: Medical and Health sciences > Health sciences

CORDIS: Health sciences

Other information

Authenticus ID: P-001-7CY

DOI: 10.1002/(sici)1097-0010(199808)77:4<527::aid-jsfa76>3.0.co;2-e

Abstract (EN): 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.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 8