Oxidation of pyrogallol to purpurogallin by crystallin catalase.

It has been recently reported that catalytic quantities of crystalline catalase, in the presence of hydrogen peroxide, can rapidly oxidize a variety of molecules larger than hydrogen peroxide and aliphatic alcohols (1). The qualitative experiments have shown that oc-naphthol and p-phenylenediamine are condensed by oxidative coupling to indophenol purple; p-aminobenzoic acid, sulfathiazole, adrenaline, ephedrine sulfate, and tyrosine were found to be coupled with catechol. Generally, amines and phenols were also found to be oxidized to colored compounds (1). There is described here a quantitative study concerning the conversion of pyrogallol (the classical peroxidase substrate) to purpurogallin by very small quantities of crystalline catalase. It will be shown that catalase, under definite conditions and at physiological pH, can perform the functions of a peroxidase. Catalase is suitable for the preparation of pure purpurogallin in less than 2 hours.