McCarron Pearse, Kotterman Michiel, de Boer Jacob, Rehmann Nils, Hess Philipp
Marine Institute, Marine Environment and Food Safety Services, Rinville, Oranmore, County, Galway, Ireland.
Anal Bioanal Chem. 2007 Apr;387(7):2487-93. doi: 10.1007/s00216-006-0935-y. Epub 2007 Jan 5.
The effect of gamma-irradiation on concentrations of hydrophilic and lipophilic phycotoxins has been investigated by use of HPLC-UV and LC-MS. Pure toxins in organic solvents and toxins in mussel (Mytilus edulis) tissues were irradiated at three different doses. In solution all toxin concentrations were reduced to some extent. Most severe decreases were observed for domoic acid and yessotoxin, for which the smallest dose of irradiation led to almost complete destruction. For pectenotoxin-2 the decrease in concentration was less severe but still continuous with increasing dose. Azaspiracid-1 and okadaic acid were the least affected in solution. In shellfish tissue the decrease in toxin concentrations was much reduced compared with the effect in solution. After irradiation at the highest dose reductions in concentrations were between ca. 5 and 20% for the lipophilic toxins and there was no statistical difference between control and irradiated samples for azaspiracids in tissue. Irradiation of shellfish tissues contaminated with domoic acid led to a more continuous decrease in the amount of the toxin with increasing dose. The effect of irradiation on the viability of microbial activity in shellfish tissues was assessed by using total viable counting techniques. Microbial activity depended on the type of shellfish and on the pretreatment of the shellfish tissues (with or without heat treatment). As far as we are aware this is the first investigation of the effectiveness of irradiation as a technique for stabilising tissue reference materials for determination of phycotoxins. Our results suggest that this technique is not effective for materials containing domoic acid. It does, however, merit further investigation as a stabilisation procedure for preparation of shellfish tissue materials for some lipophilic toxins, in particular azaspiracids. Chemical structures of the toxins investigated in the study.
利用高效液相色谱-紫外检测法（HPLC-UV）和液相色谱-质谱联用法（LC-MS）研究了γ射线辐照对亲水性和脂溶性藻毒素浓度的影响。将有机溶剂中的纯毒素以及贻贝（紫贻贝）组织中的毒素分别用三种不同剂量进行辐照。在溶液中，所有毒素浓度都有一定程度的降低。对软骨藻酸和虾夷扇贝毒素观察到最显著的降低，最小剂量的辐照就能使其几乎完全被破坏。对于pectenotoxin-2，浓度降低程度没那么严重，但仍随剂量增加而持续下降。azaspiracid-1和冈田酸在溶液中受影响最小。与溶液中的效果相比，贝类组织中毒素浓度的降低幅度大大减小。在最高剂量辐照后，亲脂性毒素浓度降低约5%至20%，并且组织中azaspiracids的对照样品和辐照样品之间没有统计学差异。辐照受软骨藻酸污染的贝类组织会导致毒素含量随剂量增加而更持续地下降。通过使用总活菌计数技术评估了辐照对贝类组织中微生物活性活力的影响。微生物活性取决于贝类的种类以及贝类组织的预处理方式（有无热处理）。据我们所知，这是首次研究辐照作为一种稳定用于测定藻毒素的组织参考材料的技术的有效性。我们的结果表明，该技术对含有软骨藻酸的材料无效。然而，作为一种稳定化程序，用于制备某些亲脂性毒素（特别是azaspiracids）的贝类组织材料，它值得进一步研究。研究中所调查毒素的化学结构。
