Standardized extraction method for paralytic shellfish toxins in phytoplankton

Abstract

The optimal conditions were established for extraction of paralytic shellfish toxins from a Danish clone of Alexandrium tamarense using extraction with acetic acid and HC1 in the concentration range 0.01-1.0 N. Physical destruction of the cells was investigated microscopically to select the most efficient extraction procedure.The toxin content was quantitated by an automized isocratic reversed-phase high-performance liquid chromatography (HPLC) method. The best results as judged from the total amount of toxins and the toxin profile were obtained using 0.05-1.0 N acetic acid and 0.01-0.02 N HC1. Hydrochloric acid in the concentration range 0.03-1.0 N caused the amount of C1 and C2 toxins to decrease sharply and concomitant increase of gonyautoxins 2 and 3.The phytoplankton extracts with 0.1 to 0.5 N acetic acid or 0.01 N HCl were stable during 6 months at -20 °C, but the extracts with HC1 > 0.02 N underwent a change in toxin profile, although the total amount of toxins was constant.

Differential inimical effects of Alexandrium spp. and Karenia spp. on cleavage, hatching, and two larval stages of Japanese pearl oyster Pinctada fucata martensii

“…After the cell densities were measured, 1 ml of A. affine and A. catenella culture medium were concentrated by centrifugation (3 Â 10 3 rpm, 4 8C, 10 min). The resulting pellets were ultrasonicated at room temperature with 4-folds volume of 0.5-N acetic acid (Ravn et al, 1995), and centrifuged (10 4 rpm, 10 min). The supernatant was centrifuged (10 4 rpm, 20 8C, 10 min) through ultrafiltration membrane (YM-10, Millipore).…”

The dinoflagellate genus Alexandrium (Halim) in New Zealand coastal waters: comparative morphology, toxicity and molecular genetics

“…Cells were harvested by gentle filtration onto GFC (Whatman) filters and the toxins extracted by sonication in 0.03N acetic acid (Ravn et al, 1995). Resolution of the toxins was carried out using the method of Oshima et al (1989).…”

Development and validation of an ultrasensitive fluorescence planar waveguide biosensor for the detection of paralytic shellfish toxins in marine algae

“…Careful selection of the extraction buffer was fundamental, not only to ensure efficient extraction of the toxins but also to avoid any interference with the immunological processes. Instead of using acetic acid or hydrochloric acid as described by Ravn et al (1995), the authors opted for PBS, pH 7.2 (Devlin et al, 2011) to avoid adverse affects on the immunoassay. The results (Fig.…”