Manganese peroxidase releases Mn(III)-carboxylic acid chelate, as peroxidase structures favor Mn(III)-chelates over free Mn(III) ions.
Mn(III) is unstable in aqueous media, therefore MnP releases it as a Mn(III)-carboxylic acid chelate. The peroxidase structure favors Mn(III)-chelates over free Mn(III) ions. 
