Cassava Root Cortex Peroxidase (CCP) as a Potential Alternative Source of Peroxidase

Abstract

Abstract Cassava is an important starch crop in the world. Starch factories normally generate a huge amount of cassava root residual which may cause pollution to the environment. In order to find some extra uses for the root cortex, cassava root cortex peroxidase (CCP) is found in quantities up to 20 mg kg −1 in deteriorated cortex tissueand demonstrates some applications similar to horseradish peroxidase (HRP). The major native CCP is a 105‐kDa dimeric peroxidase with two 54‐kDa monomers. CCP is found to be tolerant to a broad pH range from 3 to 11 with maximum activity at pH 5.0 and maintains wide temperature range activity from 20 to 70 °C with an optimum at 65 °C. This indicates CCP to be one of the most robust peroxidases. Despite simple purification with ammonium sulfate precipitation, partial purified CCP is capable of determining glucose concentrations with glucose oxidase similar capability to HRP. For application as a reporter enzyme in immunoassays, the lab‐made secondary antibody conjugated with CCPsuccessfully detects the specific antigen in Western blot analysis using achemiluminescent substrate in the same way as HRP. From the properties and results of trial applications, CCP can be equally replaced in all applications of HRP. The enzyme should be found more potential applications to gain the acceptance. Since raw material for CCP is industrially massive, it should emphasize not only optimization of purification and process cost for industry, but also commercializeto the market.