Antimicrobial activity of 8-quinolinols, salicylic acids, hydroxynaphthoic acids, and salts of selected quinolinols with selected hydroxy-acids.

Seventy-seven compounds were screened by the disc-plate method against strains of five bacteria and five fungi. A new constant was proposed to describe the antimicrobial activity of a compound in a defined system of organisms. This constant includes not only the inhibitory level of activity of the material but also the number of organisms inhibited. This constant, the antimicrobial spectrum index, was compared with the antimicrobial index of Albert.