First Paralytic Shellfish Poison(PSP) Infestation of Bivalves Due to Toxic Dinoflagellate Alexandrium tamiyavanichii, in the Southeast Coasts of the Seto Inland Sea, Japan.

Abstract

The mussel Mytilus edulis and the cultured ark shell Anadara broughtonii in the southeast coasts of the Seto Inland Sea were contaminated with paralytic shellfish poison (PSP) following the appearance of the dinoflagellate Alexandrium tamiyavanichii in early December 1999. A. tamiyavanichii plankton collected around the Straits of Naruto on December 3, 1999 showed PSP toxicity, of which 83 mol῍ was accounted for by GTX2, GTX3 and GTX4. Its specific toxicity was 112.5 fmol/cell, and one MU was equivalent to 7,200 cells. Toxicity values at the beginning of toxification were 4.7 MU/g for the ark shell and 7.3 MU/g for the mussel. In the former, the value remained at almost 4 MU/g, resulting in prohibition of marketing for about two months. In the latter, it sharply decreased to less than 4 MU/g. These bivalves collected during the toxification period were dissected into five tissues, mantle, adductor muscle, hepatopancreas, gills and "others", and submitted to high-performance liquid chromatography (HPLC). The cultured ark shell accumulated GTX2, GTX3 and STX as major components and GTX1, GTX4, GTX5, neoSTX, dcSTX and PX1ῌ3 (C1ῌC3) as minor ones. The amount of GTX3 decreased with time, while STX tended to increase. At the early stage of PSP toxification, toxins were accumulated in the gills and "others", most of which were quickly detoxified. On the other hand, PSP of the toxified mussel consisted of GTX4 as a main component, and GTX1, GTX2, GTX3, GTX5, STX and PX1ῌ2 (C1ῌC2) as minor ones. Its toxin composition pattern was similar to that of the ingested causative plankton. Its total toxin decreased soon after disappearance of the dinoflagellate. During the decrease of toxicity, PSP tended to be retained in the hepatopancreas, resulting in accumulation of 50 mol῍ of total toxin.

Non-toxic and toxic subclones obtained from a toxic clonal culture of Alexandrium tamarense (Dinophyceae): Toxicity and molecular biological feature

“…Most of toxic Alexandrium dinoflagellates including A. acatenella (Cembella et al, 1987), A. andersoni (Ciminiello et al, 2000), A. catenella (Hallegraeff et al, 1988), A. fundyense (Anderson et al, 1990), A. lusitanicum (Mascarenhas et al, 1995), A. minutum (Chang et al, 1997), A. ostenfeldii (MacKenzie et al, 2004), A. tamarense (Buckley et al, 1976, identified as Gonyaulax tamarensis, Oshima and Yasumoto, 1979, identified as G. excavata), and A. tamiyavanichii (Hashimoto et al, 2002) produce potent neurotoxins called saxitoxin analogues or paralytic shellfish toxins (PSTs), which accumulate and are metabolized in shellfish (Lin et al, 2004). The toxins cause severe symptoms in humans that ingest contaminated shellfish.…”

Comparative study on the PSP component and toxicity produced by Alexandrium tamiyavanichii (Dinophyceae) strains occurring in Japanese coastal water

“…Among the toxic Alexandrium species, Alexandrium tamiyavanichii Balech is one of the species recognized to be responsible for paralytic shellfish poisoning (PSP) in tropical and subtropical coastal waters (Fukuyo et al, 1988;Phanichyakarn et al, 1993;Usup et al, 2002) and Japanese coastal waters (Ogata et al, 1990;Hashimoto et al, 2002). Blooms due to A. tamiyavanichii have been implicated as a public health hazard in shellfish aquaculture in these regions (Hashimoto et al, 2002;Usup et al, 2002).…”

Molecular identification of toxic Alexandrium tamiyavanichii (Dinophyceae) using two DNA probes

“…A recent outbreak of poorly known A. tamiyavanichii, which produces various PSP toxins (Hashimoto et al, 2001), has had an alarming economic impact on fisheries products because of the health concerns it raises. The difficulty in monitoring this species in the field arises from its morphological similarity and cooccurrence with non-toxic A. affine and A. fraterculus.…”

“…The worldwide distribution of this genus (Hallegraeff, 1993(Hallegraeff, , 1995 increases the severity of the PSP toxin threat to the fisheries industry and human health. www.elsevier.com/locate/hal Harmful Algae 4 (2005) [984][985][986][987][988][989][990][991] Therefore, the morphological identification of Alexandrium species (Balech, 1985(Balech, , 1995Balech and Tangen, 1985;Fukuyo, 1985;Fukuyo et al, 1985;Yoshida and Fukuyo, 2000) and their ability to produce PSP toxins (Prakash, 1967;Proctor et al, 1975;Shimizu, 1978;Alan et al, 1979;Hall, 1982;Oshima et al, 1982;Maranda et al, 1985;Boyer et al, 1986Boyer et al, , 1987Cembella et al, 1987;Ogata et al, 1987;Boczar et al, 1988;Anderson et al, 1990;Anderson, 1997;Kim et al, 1993a,b;Yoshida et al, 2001;Hashimoto et al, 2001) has been studies. Recently, molecular phylogenetic analyses of the genus Alexandrium have produced a confirmation of systematic classification (Scholin et al, 1993(Scholin et al, , 1995Mendoza et al, 1995;Adachi et al, 1996a;Penna and Magnani, 2000;Usup et al, 2002;…”