液态食品中聚阳离子对外源DNA稳定性的影响

Influence of Polycations on the Stability of Exogenous DNA in Liquid Food

摘要:

随着食品安全和追溯体系的建立和完善，将DNA作为食品溯源内标物的新型技术逐渐兴起。但由于食品中存在核酸酶等多种核酸破坏因子，使得DNA作为内标物的应用被大大限制。将DNA与壳聚糖、壳寡糖和精胺的混合物加入到液态食品中，探究了聚阳离子化合物对DNA稳定性的影响。结果显示：壳聚糖、壳寡糖和精胺都可显著提高质粒DNA和PCR产物在酒类、牛奶和酸味饮品等液态食品中的稳定性，且壳聚糖对DNA的保护效果最好，可实现DNA含量在液态食品中长期保持不变。将DNA-壳聚糖复合物作为食品溯源内标物具有广阔的应用前景。

Abstract:

With the establishment and improvement of food traceability and security system，it becomes popular that using exogenous DNA as internal standards for food tracing and fake detection. However，due to nucleic acid damaging factors in food products，such as nuclease and acidic environment，low stability of DNA strongly restricts its application as food tracing standards. In this study，the stability of DNA-polycation complexes was investigated in 8 kinds of liquid foods. The results showed that polycations，especially chitosan，significantly improved the stability of DNA in alcoholic drinks，milk and sour drinks. This study indicates that DNA-chitosan complex is potential to show broad application prospect as internal standards in food traceability system.