Peroxidase, found in the roots of horseradish, actively involves in oxidizing reactive oxygen species, innate immunity, hormone biosynthesis, and pathogenesis of several diseases.

Peroxidases exist as monomers, dimmers, or tetramers. Their gene locations vary among different chromosomes. Peroxidases have some organ, tissue, cellular and sub-cellular specific distribution patterns, performing some specific functions. Peroxidases belong to a large family of isoenzymes present in almost all living organisms. These are generally heme containing enzymes ranging in Mw from 35-100 Kd. Mammalian peroxidases are much larger proteins (576-738 amino acids) than the plant counterparts[1].