Analysis pectenotoxin

Figure 5.59 Molecular structures of the diarrhetic shellfish poisons (a) pectenotoxin-6 (PTX6) (b) okadaic acid (OA) (c) dinophysistoxin-1 (DTXl) (d) yessotoxin (YTX). Reprinted from J. Chromatogr., A, 943, Matrix effect and correction by standard addition in quantitative liquid chromatographic-mass spectrometric analysis of diarrhetic shellfish poisoning toxins , Ito, S. and Tsukada, K., 39-46, Copyright (2002), with permission from Elsevier Science.

Table 9.2. Levels of pectenotoxins (pg/cell) in Dinophysis spp. determined by analysis of extracts from Dinophysis blooms or by analysis of picked Dinophysis cells... 

Draisci, R., Lucentini, L, and Mascioni, A. 2000. Pectenotoxins and yessotoxins chemistry, toxicology, pharmacology, and analysis. In Seafood and Freshwater Toxins Pharmacology, Physiology, and Detection, ed. Botana, L.M. New York Marcel Dekker, Inc., 289-324. 

Sasaki, K., Takizawa, A., Tubaro, A., Sidari, L., Loggia, R.D., and Yasumoto, T. 1999. Fluorometric analysis of pectenotoxin-2 in microalgal samples by high performance liquid chromatography. Nat Toxins 7,241-246. 

Suzuki, T, Beuzenberg, V, Mackenzie, L., and Quilliam, M.A. 2003. Liquid chromatography-mass spectrometry of spiroketal stereoisomers of pectenotoxins and the analysis of novel pectenotoxin isomers in the toxic dinoflagellate Dinophysis acuta from New Zealand. J Chromatogr A 992, 141-150. 

Preparation of extracts for chemical methods for pectenotoxins is rather simple compared to the isolation. Pectenotoxins are extracted from bivalve samples with 4-9 volumes of 80% or 90% methanol [28,29,34]. These solvent systems have been shown to be equally efficient for pectenotoxins, although 90% methanol is more efficient for DSP toxins and their esters [33]. hi some LC-MS methods, methanol extracts are directly analyzed by LC-MS [34-36]. Cleanup has been accomplished using liquid/liquid partitioning between methanolic solution and chloroform. Pectenotoxins are partitioned into the chloroform layer and toxins are analyzed directly by LC-MS after solvent evaporation and dissolution in methanol [28]. The method of McNabb et al. [33] uses a hexane wash of the crude methanolic extract to remove nonpolar lipids before direct LC-MS analysis of the relatively dilute extract (0.1 g eq./mL). Solid-phase extraction (SPE) cleanup is useful in LC-MS [29] in situations where the quantification of the toxins is interfered with by coextractives from biological matrices [31]. SPE is also useful to extract pectenotoxins from plankton net samples [6,14]. 

Dominguez, H.J., Paz, B., Daranas, A.H., Norte, M., Franco, J.M., and Fernandez, J.J. (2010) Dinoflagellate polyether within the yessotoxm, pectenotoxin and okadaic acid groups Characterization, analysis and human health implications. Toxicon, 56,191-217. 

---