Rapid Spectrophotometric Micromethod for Determination of Histaminase Activity

Abstract

IT is known that in biological systems histamine is broken down by histaminase¹. In this reaction oxygen is consumed and hydrogen peroxide is formed. A mano-metric method of measurement² is based on the oxygen consumption and a chemical method^3,4 on the production of hydrogen peroxide. In the latter method indigo is added to the incubation mixture and the discoloration of this mixture by the hydrogen peroxide formed is a measure of the enzyme activity. This is due to the peroxidatic activity of catalase mostly present in the biological fluids or tissue extracts under test. The disadvantages of the chemical method are the long incubation period of 24 h and the necessity of at least 1 ml. of serum in the case of histaminase determinations in blood.