Bock, M. J. University of Maine, mbock@maine.maine.edu
Mayer, L. M. University of Maine, lmayer@maine.maine.edu
Weston, D. P. University of California, dweston@uclink4.berkeley.edu

 
DIETARY EFFECTS ON THE DIGESTIVE CHEMISTRY OF BENTHIC POLYCHAETES: ENZYMES AND SURFACTANTS
 
Recent surveys of the digestive environments of benthic macrofauna have revealed them to be regions of high dissolved organic matter, enzyme activities and surfactants. Cross-phyletic patterns of enzyme activities suggest that the ratio of lipase to protease is indicative of diet, either in terms of diet composition and/or concentration. In addition, high concentrations of surfactants are most common in deposit feeders. We exposed an omnivore to various diets in an attempt to relate interspecies with intraspecies variability. The results show that the presence of high concentrations of surfactants is related to the inclusion of sediment in the diet. The ratio of lipase:protease is at least partially a response to the concentration of organic matter in the diet. We examined cross-phyletic data in the context of these results by relating diet to enzyme and surfactant activity. This is accomplishing by characterizing the diet in terms of selectivity for organic matter (e.g., carnivore vs. suspension feeder vs. selective deposit feeder vs. bulk deposit feeder). Although we doubt that digestive chemistry alone can be used to characterize diet, it can provide significant insight into the dietary strategies of these organisms.
 
Day: Wednesday, Feb. 3
Time: 09:45 - 10:00am
Location: Hilton of Santa Fe
 
Code: SS21WE1030H