Testing of Mode of Action of Potential Anti-fouling and Fouling-release Coatings for Microfouling in Marine Systems.
Final rept. 1 May 94-31 Apr 96,
TENNESSEE UNIV KNOXVILLE CENTER FOR ENVIRONMENTAL BIOTECHNOLOGY
Pagination or Media Count:
Tryptophan fluorescence is a non-destructive measure of bacterial biomass utilized for the determination of coating performance over time. Concurrent bioluminescence measurements give an indication of the metabolic activity of the same cell population providing an indication of sublethal stress. With this dual method biofilm density and activity from cells attached to control and test surfaces can be monitored locally and in real time in the laminar-flow environment. The destructive technique of comparing phospholipid fatty acid ratios provides a way to measure directly the health of the biofouling community and avoid tedious plate counts. Control studies have shown that a fluorescence ratio of 0.65 demonstrates an antifouling AF effect when coating values are normalized to stainless steel. There does not appear to be a significant difference between the AF efficacies of different non-toxic polymers. What is apparent is that the best results are obtained with the combination of a fouling release type polymer surface and an AF additive such as C9211. The phospholipid fatty acid ratios indicating stress in bacterial population were shown to increase in biofilms exposed to coatings with C9211 relative to coatings without the compound.
- Biological Oceanography
- Coatings, Colorants and Finishes