Purification and Partial Characterization of Polyphenol Oxidase from Sapodilla Plum (<i>Achras sapota</i>)

Abstract

The browning of fruits can be considered as an enzymatic oxidation which is believed to be one of the main causes of quality loss during post-harvest handling. The enzymes responsible for this are the oxidoreductases; the polyphenol oxidase (PPO) (monophenol, o-diphenol, oxygen oxidoreductase; EC 1.14.18.1) belongs to this group. This enzyme, which is found in the sapodilla plum (Achras sapota), was purified using a phenylsepharose and a SephacrylS-200 columns. The molecular weight of the purified enzyme was estimated to be about 66 kDa by gel filtration and 29 kDa by SDS-PAGE. A single protein band was found using the latter system (SDS-PAGE), which shows that the PPO of the pulp of the sapodilla plum may be composed of two protein subunits with similar molecular weight. The optimum pH was 7.0 and the optimum temperature 60˚C. The most effective inhibitors tested were ascorbic acid, sodium metabisulfite and acetic acid.

Comparison of biochemical properties and thermal inactivation of membrane‐bound polyphenol oxidase from three apple cultivars (Malus domestica Borkh)

“…The optimum temperature for PPO activity showed great variability depending on the enzyme source and the substrate used in the assay (Ünal & Şener, ). The optimal temperature for fruit PPO activity obtained using the same substrate ranged from 8 to 70 °C, for example, 8 °C for jackfruit PPO (Tao et al ., ), 30 °C for mPPO from snake fruit (Zaini et al ., ), 60 °C for sapodilla plum PPO (Cortez et al ., ) and 70 °C for latent PPO in loquat fruit (Sellés‐Marchart et al ., ). The optimum temperatures of FJ and GD mPPOs were within the range of these values, while the optimum temperature of GS mPPO was slightly higher than those values.…”

Partial purification, characterisation and thermal inactivation kinetics of peroxidase and polyphenol oxidase isolated from Kalipatti sapota (Manilkara zapota)

“…Similarly, POD is also involved in browning but its action is limited by the availability of hydrogen peroxide . Literature reports the characterisation of oxidative enzymes from various fruits and vegetables, such as pineapple, strawberries, grapes, and sapodilla plum . POD has received considerable attention as its role in quality deterioration and due to its use as a thermal treatment efficacy indicator.…”

Development of functional beverage from Sapodilla (Manilkara Zapota L.) fruit

“…Polyphenol oxidase (PPO) causes the enzymatic browning of fruits and vegetables (Cortez et al, 2013). PPO is less reactive below the pH range of 5 and 7, which is the optimum pH range for PPO activity (Martinez and Whitaker, 1995).…”