Austrovenus

The cockle, Austrovenus stutchburyi from New Zealand contained brevetoxin Bi (225) [230] and the greenshell mussel, Pema canaliculus contained brevetoxin B3 (226) [231]. A further brevetoxin analogue, brevetoxin B2 (227) was isolated from the hepatopancreas of P. canaliculus [232], while the major toxin in neurological shellfish poisoning (NSP) associated with P. canaliculus was identified as brevetoxin B4 (228) [233]. 

Ishida, H., Nozawa, A., Totoribe, K., Muramatsu, N., Nukaya, H., Tsuji, K., Yamaguchi, K., Yasumoto, T, Kaspar, H., Berkett, N., Kosuge, T. 1995. Brevetoxin-B-1, a new polyether marine toxin from the New Zealand shellfish, Austrovenus stutchburyi. Tetrahedron Letters 36, 725-728. 

Ishida, H., Nozawa, A., Nukaya, H., Rhodes, L., McNabb, P, Holland, PT, Tsuji, K. 2004a. Confirmation of brevetoxin metabolism in cockle, Austrovenus stutchburyi, and greenshell mussel, Perna canaliculus, associated with New Zealand neurotoxic shellfish poisoning, by controlled exposure to Karenia brevis culture. Toxicon 43, 701-712. 

Ishida et al. (1995) hrst described a new water-soluble polyether BTX analogue (Bl) isolated from New Zealand cockles (Austrovenus stuchburyi). BTX-Bl is the taurine conjugate of PbTx-2 and was the predominant BTX metabolite produced within the cockle. BTX-Bl was not ichthyo-toxic. It was only found in low levels in Greenshell mussels (Perna canaliculus) and not at all in Pacihc oysters (Crassostrea gigas). PbTx-3 was found in all three species (Nozawa et al., 2003) and parent PbTx-2 in Cr. gigas (Ishida et al., 1996). 

Ishida, H., Nozawa, A., Hamano, H., Naoki, H., Fujita, T., Kaspar, H.F., and Tsuji, K. Brevetoxin B5, a new brevetoxin analog isolated from cockle Austrovenus stutchburyi in New Zealand, the marker for monitoring shellfish neurotoxicity, Tet. Lett., 45, 29-33, 2004a. 

Ishida, H., et al., Brevetoxin Bl, a poly ether marine toxin from the New Zealand sheMtsh Austrovenus stutchburyi. Tetrahedron Lett., 36, 725-728, 1995. 

Ishida, H., et al.. Comparative concentrations of brevetoxins PbTx-2, PbTx-3, BTX-B1 and BTX-B5 in cockle, Austrovenus stutchburyi, greenshell mussel, Pema canaliculus, and Pacific oyster, Crassostrea gigas, involved in neurotoxic shellfish poisoning in New Zealand, Toxicon, 43, 779-789, 2004. 

This first sulfur-containing brevetoxin was isolated from a New Zealand mollusk, Austrovenus stutchburyi, but it is very likely that its real origin is a dinoflagellate ingested by the animal, with or without later modification by the mollusk. 

The poisoning that occurred in New Zealand in 1993 after the consumption of oysters Crassostrea gigas) and cockles (Austrovenus stutchhuryi), led to the discovery of BTX-B5, a new brevetoxin whose minimum lethal dose is 0.3-0.5 mgkg (intraperitoneal injection in mice Ishida et al, 2004a, 2004b, 2004c). 

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