This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Reprints and Permissions Copyright Information Books from ASM Press MicrobeWorld Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Korber, D. R. Articles by Caldwell, D. E. Search for Related Content PubMed PubMed Citation Articles by Korber, D. R. Articles by Caldwell, D. E. Agricola Articles by Korber, D. R. Articles by Caldwell, D. E.

 Previous Article  |  Next Article 

Appl. Environ. Microbiol., 09 1997, 3352-3358, Vol 63, No. 9
Copyright © 1997, American Society for Microbiology

Substratum topography influences susceptibility of Salmonella enteritidis biofilms to trisodium phosphate

DR Korber, A Choi, GM Wolfaardt, SC Ingham and DE Caldwell
University of Saskatchewan, Saskatoon, Canada. Korber@sask.usask.ca

Established (48- and 72-h) Salmonella enteritidis biofilms grown in glass flow cells with or without artificial crevices (0.5-, 0.3-, and 0.15-mm widths) were subjected to a 10% trisodium phosphate (TSP) solution under different flow regimens (0.3, 0.6, 1.2, and 1.8 cm s-1). The abundance of biofilm remaining after TSP treatment, the biocidal efficacy of TSP, and the factors which contributed to bacterial survival were then evaluated by using confocal laser microscopy and a fluorescent viability probe. Biofilm age affected the amount of biofilm which remained following a 15-s exposure to TSP. After TSP treatment of 48-h biofilms, 29% of the original biofilm remained at the biofilm- liquid interface, whereas 75% of the biofilm remained at the base (the attachment surface). Following TSP treatment of 72-h biofilms, 27% of the biofilm material remained at the biofilm-liquid interface, 73% remained at the 5-micron depth, and 91% remained at the biofilm base. Results obtained using the BacLight viability probe indicated that TSP exposure killed all the cells in 48-h biofilms, whereas in the thicker 72-h biofilms, surviving bacteria (approximately 2% of the total) were found near the 5- and 0-micron depths. In the presence of artificially constructed crevices, an inverse relationship was shown to exist between bacterial survival (ranging from approximately 13 to 83% of total biofilm material) and crevice width. This relationship was further influenced by the velocity of TSP flow; high TSP flow velocities (1.8 cm s-1) resulted in the lowest number of surviving bacteria at the base of crevices (approximately 42% survival). Extended time courses demonstrated that after TSP stress was relieved, biofilms continued to grow within crevices but not in systems without crevices. It is suggested that advective TSP flux into crevices and through the biofilm matrix was enhanced under conditions of high flow. These results suggest that the inherent roughness of the substratum on which the biofilm was grown and the timing of TSP application are important factors controlling the efficacy of TSP treatment.

This article has been cited by other articles:

• Auerbach, I. D., Sorensen, C., Hansma, H. G., Holden, P. A. (2000). Physical Morphology and Surface Properties of Unsaturated Pseudomonas putida Biofilms. J. Bacteriol. 182: 3809-3815 [Abstract] [Full Text]  
• Elortondo, F.J. P., Salmeron, J., Albisu, M., Casas, C. (1999). Formacion de peliculas biologicas en la industria alimentaria / Biofilms in the food industry. Food Science and Technology International 5: 25-30 [Abstract]