Effect of L -cysteine, P otassium Metabisulfite, Ascorbic Acid and Citric Acid on Inhibition of Enzymatic Browning in Longan
Nutkridta Pongsakul, Bundit Leelasart and Nuansri Rakariyatham** Author for corresponding; e-mail address: nuansri1@yahoo.com
Volume: Vol.33 No.1 (JANUARY 2006)
Research Article
DOI:
Received: 12 April 2005, Revised: -, Accepted: 25 September 2005, Published: -
Citation: Pongsakul N.., Leelasart B.. and Rakariyatham N.., Effect of L -cysteine, P otassium Metabisulfite, Ascorbic Acid and Citric Acid on Inhibition of Enzymatic Browning in Longan, Chiang Mai Journal of Science, 2006; 33(1): 137-141.
Abstract
The effect of different anti-browning agents on partially purified longan polyphenol oxidase (PPO) activity was investigated by spectrophotometry, using catechol as a phenolic substrate. For this purpose, L-cysteine, potassium metabisulfite, ascorbic acid, and citric acid were used to inhibit the activity of longan PPO at different concentrations (0-10 mM). Lcysteine was found to be the most potent anti-browning agent (L-cysteine > potassium metabisulfite > ascorbic acid > citric acid). Pre-incubation of PPO with some anti-browning agents increased the extent of inhibition.