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

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。

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.