Extraction, purification and processing stability of peroxidase from plums (Prunus domestica)

• Main Authors: Elena Enachi, Leontina Grigore-Gurgu, Iuliana Aprodu, Nicoleta Stănciuc, Istvan Dalmadi, Gabriela Bahrim, Gabriela Râpeanu, Constantin Croitoru
• Format: Article
• Language: English
• Published: Taylor & Francis Group 2018-01-01
• Series: International Journal of Food Properties
• Subjects: Plums; peroxidase; enzymatic browning; inactivation kinetics
• Online Access: http://dx.doi.org/10.1080/10942912.2018.1560311

Peroxidase (POD) was extracted from Prunus domestica and partially purified by three methods: ammonium sulfate precipitation, hydrophobic interaction chromatography, and ion exchange chromatography, respectively. The selected procedure allowed a 26.33-fold purification, and the molecular mass estimated by SDS-PAGE was 58 kDa. The purified enzyme presented enzymatic activity toward guaiacol, pyrogallol, catechol, and showed no activity toward ferulic, caffeic, and p-coumaric acids. In terms of optimum parameters for activity, the pH was 6.5, whereas the temperature was 25°C. The enzyme exhibited high stability in the pH range of 5.0–7.0 and in the temperature range of 25–70°C. The most potent inhibitors of POD were L-cysteine and sodium metabisulfite. The thermal inactivation displayed a first-order kinetic model, with an activation energy of Ea 84.79 ± 2.2 kJ/mol. POD extracted from plums exhibited high stability at high-pressure treatment, maintaining over 50% of the initial activity even at 700 MPa.