The Antibacterial Activity of Haematin

SUMMARY: Haematin in concentrations of 1/1,000,000– 1/2,000,000 inhibited the growth of a number of bacteria most of which were aerobic sporing bacilli. Deuterohaematin and mesohaematin were also inhibitory, but not haematohaematin, urohaematin and a number of iron-free porphyrin derivatives. In a few cases whole blood was inhibitory, but generally only trypsin-digested laked red cells. The mechanism of the antibacterial activity is not understood.