小鼠法检测脂溶性贝类毒素假阳性来源分析  

Inquiry and Analysis of Sources of False Positive Results for the Detection of Fat Soluble Shellfish Toxins by the Mouse Bioassay

作　　者：刘晓玉[1] 徐静[2] 晚观生 刘慧颖[2] 曹际娟[1,2] 

机构地区：[1]大连工业大学,辽宁大连116034 [2]辽宁出入境检验检疫局,辽宁大连116001

出　　处：《食品科学》2016年第20期157-161,共5页Food Science

基　　金：国家公益性行业(质检)科研专项(201310141)

摘　　要：目的:探讨牡蛎样品中游离脂肪酸含量随贮存温度和时间的变化,以期对小鼠法检测脂溶性贝类毒素假阳性结果的来源进行探索和分析。方法:采用三氟化硼甲酯化法对脂肪酸进行衍生化,使用固定液100%二氰丙基聚硅氧烷的毛细管色谱柱对牡蛎样品中游离脂肪酸进行检测。结果:-10℃和-20℃贮存样品中游离脂肪酸总含量随时间延长先增加后减少,之后再缓慢增加,4℃贮存样品中游离脂肪酸总含量随贮存时间的延长一直缓慢增加;贮存时间相同,-20℃贮存样品游离脂肪酸含量明显高于-10℃。在3种贮存温度条件下,高毒游离脂肪酸C_(20:5n-3)和低毒游离脂肪酸C_(22:6n-3)含量均随时间延长而增长。5个月后-20℃贮存样品中C_(20:5n-3)含量为136.79μg/g,达到小鼠最小致死量(6 mg)45%;若取2.5倍称样量进行实验,可导致小鼠法假阳性结果。结论:牡蛎样品中高毒游离脂肪酸是小鼠法检测脂溶性贝类毒素假阳性结果的重要来源,且高毒游离脂肪酸含量随贮存温度和时间变化呈增长趋势。Objective： To examine the changes in free fatty acid contents in oyster with storage temperature and storage timefor the purpose of exploring and analyzing the sources of false positive results in mouse bioassay for fat soluble shellfishtoxins. Methods： Methyl esterification of free fatty acids was carried out with boron trifluoride in methanol. The productswere analyzed by gas capillary chromatography with a column coated with a 100% cyanopropyl polysiloxane stationaryphase. Results： The total content of free fatty acids stored at ？10 ℃ and ？20 ℃ increased at first, then decreased, andslowly increased again with prolonging time. When the sample was stored at 4 ℃, there was a slowly increasing trend. Thecontent of free fatty acids stored at ？20 ℃ was significantly higher than at ？10 ℃ at the same storage time. At all the threestorage temperatures, the contents of the highly toxic free fatty acid C20：5n-3 and the low toxic fatty acid C22：6n-3 kept increasingthroughout the storage period. Five months later, C20：5n-3 in oyster stored at ？20 ℃ was 136.79 μg/g, which was 45% of thelethal dose for mice. If 2.5-fold weight of the oyster sample was used, the mice would die, leading to false positive results inmouse bioassay for fat soluble shellfish toxins. Conclusion： The high toxic free fatty acid in oyster samples was importantsource of false positive results in mouse bioassay for fat soluble shellfish toxin, and the content of high toxic free fatty acidin oyster samples presented an increasing trend at three temperatures as time goes by.

关 键 词：小鼠法 脂溶性贝类毒 假阳性 游离脂肪酸 

分 类 号：TS254.4[轻工技术与工程—水产品加工及贮藏工程]