Purification and thermostability of isoperoxidase from oranges

• Published in: Phytochemistry (Oxford) Vol. 49; no. 1; pp. 29 - 36
• Main Author: Clemente, E
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier Ltd 01.09.1998; Elsevier
• Subjects: Biological and medical sciences; Citrus sinenis; Enzymes; Food industries; Fundamental and applied biological sciences. Psychology; isoperoxidase; Metabolism; Non alcoholic beverage industries and mineral waters; oranges; Plant physiology and development; purification; Rutaceae; thermostability; oranges; isoperoxidase; thermostability; Citrus sinenis; purification; Rutaceae; Purification; Citrus sinensis; Fruit; Enzyme; Isozyme; Citrus fruit; Thermal stability; Characterization; Peroxidases; Enzymatic activity; Orange juice; Dicotyledones; Quality; Angiospermae; Spermatophyta; Peroxidase; Oxidoreductases
• ISSN: 0031-9422; 1873-3700
• DOI: 10.1016/S0031-9422(97)00967-9

Soluble and ionically bound peroxidase were extracted from oranges ( citrus sinenis (L.) Osbeck cultivar Large Valencia, Small Sweet and Navel. Cationic and anionic isoperoxidase were obtained by Rotofor and ion-exchange chromatography. The pI for the soluble isoenzymes (4.5 to 9.0) was measured using a surface electrode and the M r (22 k to 44 k) was estimated by gel-filtration. The purified isoperoxidases (C 1 and C 2) were more heat stable than the peroxidase present in the crude extract. The inactivation of orange peroxidase activity in a mixture or individually in a purified state, was found to be non-linear with heating time.