First evidence of Okadaic acid acyl-derivative and Dinophysistoxin-3 in mussel samples collected in Chiloe Island, Southern Chile

This paper shows the detection of Diarrhetic Shellfish Poison (DSP) phycotoxins, using HPLC-FLD with pre-column derivatization procedure and HPLC-MS methods, in the analysis of shell-fish extracts tested positive with the official DSP mouse bioassay. The shellfish samples were collected in Chiloe Island, Southern of Chile. The amount of Dinophysistoxin-3 (DTX-3) measured in the shellfish extracts were in average above the international safe limits for DSP content in the shellfish extracts analyzed. As internal control of detection and recovery, DTX-1 analytical standard was spiked into dichloromethane-clean shellfish extracts in order to calculate de extraction recovery of DTX-1. The average recovery was 97%. From all DSP toxins analyzed, the hydrolyzed extract samples appeared mainly DTX-3 in concentrations ranging from 99.40 ± 1.22 to 257.73 ± 12.46 ng/g digestive-glands. The acyl-Okadaic Acid (acyl-OA) was also detected in some samples, ranging from 1.02 ± 1.4 to 3.07. ± 1.6 ng of