Effect of Dilution Rate on Azadinium spinosum and Azaspiracid (AZA) Production in Pilot Scale Photobioreactors for the Harvest of AZA1 and -2

摘要

In 1995 the first azaspiracid (AZA) shellfish poisoning occurred in the Netherlands with symptoms similar to diarrhetic shellfish poisoning (McMahon and Silke 1996). A few years later, the toxin was identified and named azaspiracid (Satake et al. 1998) and then structurally revised (Nicolaou et al. 2004). Afterwards, a large number of analogues were identified in mussel tissues using biological assay and chemical analysis including liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS),i.e. AZA2-32 (Diaz Sierra et al. 2003; James et al. 2003; McCarron et al. 2009; Ofuji et al. 1999, 2001; Rehmann et al. 2008). Nevertheless, since the first known poisoning event, it took 12 years until the discovery of a primary producer, the dinoflagellate A. spinosum (strain 3D9) (Krock et al. 2008, 2009; Tillmann et al. 2009). This small dinoflagellate (12-16 mum length and 7-11 mum width) produces AZA1 and -2 in culture (Tillmann et al. 2009). Since this recent discovery the organism has been encountered in different parts of the world: Ireland(Salas et al. 2011), France (Nezan et Siano, personal communication), Mexico (Hernandez-Becerril et al. 2010), Argentina (Akselman and Negri 2012), and AZA occurrences are now recognized as a worldwide phenomenon. Until now, AZAs were purified and isolated from contaminated bivalves, as it has been originally carried out with other marine biotoxins: okadaic acid group toxins, brevetoxins, saxitoxins, yessotoxins, domoic acid, cyclic imines and pectenotoxins (Rundberget et al. 2007). However, severe toxic events are required to obtain pure standards from contaminated bivalves, even though recovery has been improved recently and the number of purification steps required to purify AZAs from complex matrices reduced (Kilcoyne et al. 2012; Perez et al. 2010).