Influence of the addition of mineral salts on the inhibitory activity of strains of the Arthrinium genus

The influence which the addition of certain mineral salts has on the inhibiting activity of strains belonging to the Arthrinium genus was studied. The salts employed were AgNO3, FeCl2, MnCl2 and CuSO4, in concentrations of 10, 50, 100, 150 and 200 mg/l, in the presence of Bacillus subtilis, Enterobacter cloacae, Staphylococcus aureus, Escherichia coli, Serratia marcescens, Klebsiella pneumoniae, Candida albicans and Aspergillus niger. For B. subtilis and S. aureus greater inhibition was observed after the addition of FeCl2 (200 mg/l) and MnCl2 (10 mg/l). E. coli showed a greater sensibility in the presence of AgNO3 (200 mg/l) and CuSO4 (150 mg/l). Inhibition before Enterobacter cloacae and Serratia marcescens was not increased by the addition of any of the salts. The addition of MnCl2 at 10 mg/l concentration to the basal medium showed a considerable increase of inhibitory activity over Klebsiella pneumoniae and Candida albicans. Activity for Aspergillus niger decreased when any of the salts were added to the medium.