Antimicrobial activity of calixarenes

The pursuit of antimicrobially active compounds against a variety of microorganisms is an area of intense and important research. In the present study, we examined the relative antimicrobial activity of calixarenes having different side chains, moieties and/or substitution groups against a diverse set of bacteria and fungi. Antimicrobial activity against the various species was evaluated by growth rate and inhibition rate comparisons to distinguish between the compounds for this desired property. Preliminary screening of 57 calixarenes was conducted to assay their potential as antimicrobially active compounds against Corynebacterium. Of these compounds, seven calixarenes numbered 25, 26, 27, 28, 30, 34 and 50 were found to exhibit suitable antimicrobial activity. These seven samples were then further tested to elucidate any antimicrobial activity they might have versus additional species. After examining the growth and inhibition values of these selected compounds, calixarenes sample numbers 25, 26, 27, 28 and 50 were shown to also display antimicrobial activity against Fusarium solani f. sp. mori [F.s.-26] with an inhibition range of approximately 60-70%. Additionally, sample numbers 25, 26, 27, and 28 exhibited excellent and selective antimicrobial activity against the fungal strains, Rosellinia necatrix [R-8], and Colletotrichum dematium [C.d. 8901].