Search tips
Search criteria 


Logo of aemPermissionsJournals.ASM.orgJournalAEM ArticleJournal InfoAuthorsReviewers
Appl Environ Microbiol. 1990 June; 56(6): 1678–1682.
PMCID: PMC184492

Effect of Cetylpyridinium Chloride on Microbial Adhesion to Hexadecane and Polystyrene


Microbial adhesion at the oil-water interface is a subject of both basic interest (e.g., as a technique for the measurement of hydrophobicity) and applied interest (e.g., for use in two-phase oil-water mouthwashes for the desorption of oral microorganisms). In general, surfactants inhibit microbial adhesion to oils and other hydrophobic surfaces. In the present study, we demonstrated that the cationic surfactant cetylpyridinium chloride (CPC) significantly enhanced microbial adhesion to hexadecane and various oils, as well as to the solid hydrophobic surface polystyrene. CPC increased adhesion to hexadecane of Escherichia coli, Candida albicans and Acinetobacter calcoaceticus MR-481 and of expectorated oral bacteria from near 0% to over 90%. The CPC concentration required for optimal enhancement of adhesion was a function of the initial cell density. This phenomenon was inhibited by high salt concentrations and, in the case of E. coli, by a low pH. CPC-pretreated cells were able to bind to hexadecane, but CPC-pretreated hexadecane was unable to bind untreated cells. Another cationic, surface-active antimicrobial agent, chlorhexidine gluconate, was similarly able to promote microbial adhesion to hexadecane. The results suggest that (i) CPC enhances microbial adhesion to hexadecane by binding via electrostatic interactions at the cell surface, thus diminishing surface charge and increasing cell surface hydrophobicity, and (ii) this phenomenon may have applications in oral formulations and in the use of hydrocarbon droplets as a support for cell immobilization.

Full text

Full text is available as a scanned copy of the original print version. Get a printable copy (PDF file) of the complete article (849K), or click on a page image below to browse page by page.

Images in this article

Click on the image to see a larger version.

Articles from Applied and Environmental Microbiology are provided here courtesy of American Society for Microbiology (ASM)