Structure-Antimicrobial Activity Relationship for a New Class of Antimicrobials, Silanols, in Comparison to Alcohols and Phenols

摘要

Concerns for microbial contamination and infection to the general population and military personnel have greatly increased due to the increased potential for bio-terrorism and microbial threats to health. Desirable antimicrobials are designed to be environmentally benign, strongly effective to various microorganisms, and economically affordable. We have recently discovered a new class of silicon based antimicrobials called silanols (R(CH3)2SiOH). The antimicrobial activity of the silanols was at least twice as strong as their analogous alcohols. The silanols are prepared from the hydrolysis of chlorosilanes. The silanols can be prepared by low cost processes. Silanols degrade into the environmentally benign species of silica, CO2 and H2O instead of accumulating in the environment. Understanding the mechanisms of the antimicrobial action is critical for the development of antimicrobials with improved antimicrobial effects. A structural XIV dependency of the antimicrobial activity was investigated with four bacteria, Escherichia coli, Staphylococcus aureus, Psudomanos aeruginosa, and Enterococcus faecalis. Silanols, alcohols with structures analogous to the silanols, (R(CH3)2SiOH), and substituted phenols were evaluated as a single class of materials. The minimum lethal concentrations (MLC) defined as the concentration required for a 7-log reduction in viable bacteria after one hour exposure period was used to measure the antimicrobial activity. The octano V water partition coefficients (log P) and H-bond acidities (-v) were used as the dispersive and the polar structural parameters of the antimicrobials. The correlations between the antimicrobial activity and the structural parameters of the antimicrobials demonstrated a linear free-energy relationship. The correlation models established by using the multiple regression analysis and their significantly high correlation.