Polyphenoloxidase from guava (Psidium guajava L.)

Polyphenoloxidase (PPO) was isolated from guava (Psidium guajava L., cv. Kampuchea). Purification by acetone precipitation and dialysis of the Amicon concentrate resulted in 4.9‐fold and 17.2‐fold purification of the dialysed crude extract respectively. Polyacrylamide gel electrophoresis indicated t...

Full description

Saved in:
Bibliographic Details
Main Authors: Augustin, M.A., Ghazali, Hasanah M., Hashim, Hasimah
Format: Article
Published: John Wiley & Sons 1985
Online Access:http://psasir.upm.edu.my/id/eprint/114332/
https://onlinelibrary.wiley.com/doi/10.1002/jsfa.2740361209
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Polyphenoloxidase (PPO) was isolated from guava (Psidium guajava L., cv. Kampuchea). Purification by acetone precipitation and dialysis of the Amicon concentrate resulted in 4.9‐fold and 17.2‐fold purification of the dialysed crude extract respectively. Polyacrylamide gel electrophoresis indicated that PPO had a molecular weight in the region of 120000–140000. The pH optimum of the enzyme was found to be 7.2. Heat inactivation studies showed that heating for 1.1, 3.5, and 10.1 min at 75, 65 and 55°C respectively caused a 50% loss in enzymic activity. The enzyme‐catalysed browning reaction was significantly inhibited in the presence of sodium metabisulphite, L‐cysteine hydrochloride and ascorbic acid.