ABSTRACT
The Minimum Inhibitory Concentrations were determined by observing the presence or absence of microbial growth in a series of test tubes containing various concentrations of the test compound in a liquid medium. Due to the insolubility of most tin steroids in water, an initial 1/100 dilution of the compounds was made in dimethylformamide (DMF). After the dilution in DMF, serial dilutions were made using either nutrient broth or Sabouraud dextrose broth. The tubes were then inoculated with 0.1 ml of a broth culture of bacteria or 0.1 ml of a fungal spore suspension. The activity of the 12 tin steroids against the Gram-negative bacterium, Klebsiella pneumoniae, was poorer than that of the well-documented tin ester, tributyltin maleate. Tributyltin steroids, despite their high tolerance by mice, behave like most tributyltin esters in their antimicrobial activity against bacteria and fungi in both broth cultures and on fabrics.
