Meeting Abstract

P3.26A  Friday, Jan. 6  High Performance Liquid Chromatography (HPLC) analysis of Vitamin D3 in a Daphnia microcosm experiment CARRERA, JV*; CATLIN, D; WALLING, KM; MONAGHAN, C; BOWLES, S; SCHMITTHENNER, H; CODY, JC; TAN, LT; CONNELLY, SJ; Rochester Institute of Technology

Increasing levels of ultraviolet radiation (UVR) in freshwater systems has been detected with constantly changing environmental conditions. Freshwater ecosystems are particularly susceptible due to their high exposures to solar radiation, and the organisms of these systems must adapt accordingly. The overall purpose of this collaborative research is to determine the survival and reproduction rates of vitamin D3 exposed Daphnia spp. under varying ultraviolet radiation (UVR) conditions. The vitamin D3 was assessed for its photoprotective properties in Daphnia spp. under chronic and acute UV-A and UV-B exposure. Vitamin D3 and its metabolites were analyzed in experimental samples using High Performance Liquid Chromatography (HPLC). We have developed an improved method of HPLC analysis by adjusting the variable parameters to increase sensitivity in the biological samples. Vitamin D3 and several metabolites were recovered in the Daphnia spp., algae food source (Selenastrum capricornutum), and aqueous samples following UV exposure in a controlled microcosm setting. Vitamin D3 was also recovered in the control sample (0% vitamin D3 addition), indicating a strong role of algae in the transport of nutrients to the Daphnia spp. Algae were also tested under stressed conditions to better understand the metabolic effects of vitamin D3 and UVR with and without Daphnia (spp.). Through this experimentation, we can better understand the source of vitamin D3 metabolic conversion in freshwater ecosystems and the potential for the vitamin D3 to act as a reducer of environmental stresses in the Daphnia spp.