Abstract:
The Thunnini, or tuna, comprise many species with very different commercial values. The principal raw tuna product on the market is sashimi, for which the species used is difficult to identify through conventional morphological analysis. The present study amplified the cytochrome b gene (Cytb) of 4 major tuna species used for preparing sashimi-yellowfin tuna (Thunnus albacares), southern bluefin tuna (Thunnus maccoyii), bigeye tuna (Thunnus obesus), and Atlantic bluefin tuna (Thunnus thynnus)-and 4 species commonly mislabeled as components of tuna sashimi-albacore tuna (Thunnus alalunga), skipjack tuna (Katsuwonus pelamis), striped marlin (Tetrapturus audax), and swordfish (Xiphias gladius). Polymerase chain reaction (PCR) amplicons were digested with 5 restriction enzymes-Eco147 I, Hinf I, Mbo I, Xag I, and Hind II-to obtain characteristic restriction maps of the above-mentioned raw tuna species and the commonly mislabeled species. An identification method using PCR restriction fragment length polymorphism (PCR-RFLP) was established and validated using 39 commercial tuna sashimi samples, which verified that this method provides results consistent with those obtained by classical sequencing. PCR-RFLP has several advantages over classical sequencing, such as simplicity, speed and accuracy. This technique could support species identification for raw tuna and sashimi.
摘要:
Thunnini,或者金枪鱼,包括许多具有不同商业价值的物种。市场上主要的生金枪鱼产品是生鱼片,使用的物种很难通过常规的形态学分析来鉴定。本研究扩增了用于制备生鱼片黄鳍金枪鱼(Thunnusalbacares)的4种主要金枪鱼的细胞色素b基因(Cytb),南部蓝鳍金枪鱼(Thunnusmaccoyii),大眼金枪鱼(Thunnusobesus),和大西洋蓝鳍金枪鱼(Thunnusthynnus)-和4种通常被错误标记为金枪鱼生鱼片-长鳍金枪鱼(Thunnusalalunga)的成分的物种,金枪鱼(Katsuwonuspelamis),条纹马林鱼(Tetrapturusaudax),和旗鱼(剑兰)。用5种限制酶-Eco147I消化聚合酶链反应(PCR)扩增子,如果我,MboI,XagI,和HindII-以获得上述原始金枪鱼物种和通常错误标记的物种的特征限制图。建立了使用PCR限制性片段长度多态性(PCR-RFLP)的鉴定方法,并使用39个商业金枪鱼刺身样品进行了验证,这证实了该方法提供的结果与通过经典测序获得的结果一致。PCR-RFLP比经典测序有几个优点,比如简单,速度和准确性。该技术可以支持对生金枪鱼和生鱼片的物种鉴定。