This report covers high performance liquid chromatography (HPLC) derived pigment based chemotaxonomy for phytoplankton studies in a turbid coastal environment. Sediment resuspension brings detritus with pheopigments and other chlorophyll (CHL) breakdown products into the water column and hampers data interpretation. Two hundred sixty six water samples from Florida Bay were analyzed from monthly collections (Sept. 2000–Aug. 2002). Comparing biomarker estimated CHLa to measured CHLa, we found a mean of 105.4% (Std. Dev.=24.7; R²=0.9547) and when data was restricted to those samples with <10% pheopigments, estimations improved to 102±16%. It is concluded that all HPLC studies on phytoplankton communities must report the percentage pheopigments.

This study compared different extraction and high performance liquid chromatography (HPLC) combinations for the analysis of chloropigments in sediments and microalgae (phytoplankton). A significant literature review is also included. Extractants in the present study included 100% acetone, tetrahydrofuran, and an aqueous mixture of methanol, acetone, and dimethylformamide. HPLC methods involved gradient elution methods with or without ion pairing reagents over C₁₈ silica based columns. Though slight differences were found, most notably with the extraction of steryl chlorin esters, this intercomparison reveals that both extraction and HPLC protocols investigated, in any combination, perform well for the analysis of chlorophylls and their derivatives in sediment and phytoplankton samples.