Purification and characterisation of polyphenol oxidase from leaves of Cleome gynandra L.

► We purified and characterised a 52.6 kDa PPO from Cleome gynandra leaves (CgPPO). ► CgPPO was optimally active and stable at pH 8.0/60 °C and pH 3.0 to 9.0/below 60 °C. ► CgPPO's diphenolase activity was higher than monophenolase and triphenolase activities. ► CgPPO showed a substrate specificity toward methylated and methoxylated substrates. ► CgPPO's activity was completely inhibited by Hg2+, strong reductants and thiols.