Influence of the heat treatment and EDTA on the haemagglutinating activity of the Eutirucallin.

A. Eutirucallin (1.8 µg) was incubated for 20 min at 25, 35, 45, 55, 65, 75, 85 and 95°C. After 60 min of sedimentation at room temperature the haemagglutinating activity was evaluated. B. The Eutirucallin (1.8 µg) was incubated with EDTA in the concentrations of 10, 50 and 100 mM, and kept for 18 h at 4°C. Following to that the haemagglutinating activity was evaluated. Human erythrocytes A+ at 2% were used in both assays. The positive haemagglutination was indicated by the formation of a uniform coating of red blood cells in the surface of the U plates, and its absence was determined by the sedimentation of the cells in the bottom of the plates.