基于DNA条形码技术常见肉类掺假鉴别技术的研究

Techniques for Identifying Common Meat Adulterations Based on DNA Barcoding

摘要:

根据市场上常见的肉类掺假情况，本研究通过提取生鲜牛肉、羊肉、猪肉和鸭肉基因组DNA，按一定比例进行预混合，构建牛肉掺猪肉、羊肉掺猪肉、牛肉掺鸭肉和羊肉掺鸭肉4种掺假模型。通过引物COI-1和COI-2进行PCR扩增和测序比对，建立基于COI基因的动物源性食品的掺假判别方法。根据实验所得纯肉DNA提取率T实现DNA水平到肉水平掺假比例的换算。在肉的掺假水平上，引物COI-2检测效果较好，对牛-猪、羊-猪、牛-鸭和羊-鸭模型掺假物的检出限分别为5%、8%、1%和4%。对采集的28个批次的肉制品进行检测，结果表明：28个样品中89%的样品与产品标签标识的成分相符。建立的基于DNA条形码技术的检测方法可作为一种简单、快速、有效的分子鉴定技术，可以直接应用于研究物源性食品的种类和掺假鉴定。

Abstract:

According to the cases of common meat adulteration seen in the market, four kinds of adulteration models were built: mixed beef-pork, mutton-pork, beef-duck, and mutton-duck by extracting genomic DNAs from fresh beef, mutton, pork, and duck and premixing them at certain ratios. Through polymerase chain reaction (PCR) and sequence comparison using the universal primers COI-1 and COI-2, a COI gene–based method was established to detect adulteration in foods of animal origin. According to the pure meat DNA extraction rate T obtained from the experiment, the conversion of the adulteration ratio from the DNA level into the meat weight level was achieved. At the meat weight level, COI-2 primers provided a relatively accurate detection, and the detection limits of beef-pork, mutton-pork, beef-duck, and mutton-duck adulteration models were 5%, 8%, 1%, and 4%, respectively. The method was tested on 28 batches of collected meat product samples, and the ingredients of 89% of the identified samples were consistent with those described on the product labels. As a simple, rapid, and effective molecular identification approach, DNA barcoding can be directly applied to determine the animal species present in foods of animal origin and to detect adulteration.