Turkish Journal of Chemistry
DOI
-
Abstract
Polyphenol oxidase (PPO, EC 1.14.18.1) was extracted from quince (Cydonia oblonga) by using 0.1 M phosphate buffer, pH 6.8. The polyphenol oxidase of quince was partially purified by (NH_{4})_{2}SO_{4} and dialysis. Substrate specificity experiments were carried out with catechol, pyrogallol, L-DOPA, p-cresole and tyrosine. Catechol was the most suitable substrate compound for quince PPO. The Michaelis constants were 4.54 mM, 7.35mM and 17.8 mM for catechol, pyrogallol and L-DOPA, respectively at 25^oC. The optimum pH and temperature were determined with the specific substrate catechol as 8.0 and 40$^oC, respectively. Of eight inhibitors tested L-cysteine, ascorbic acid and potassium cyanide were the most effective against quince PPO.
Keywords
Quince, polyphenoloxidase, purification, characterization
First Page
97
Last Page
104
Recommended Citation
YAĞAR, HÜLYA and SAĞIROĞLU, AYTEN (2002) "Partially Purification and Characterization of Polyphenol Oxidase of Quince," Turkish Journal of Chemistry: Vol. 26: No. 1, Article 11. Available at: https://journals.tubitak.gov.tr/chem/vol26/iss1/11
