牛乳中A2β-酪蛋白功效特点及其检测方法研究进展

Research progress on efficacy characteristics and detection methods of A_(2)β-casein in milk

牛乳总蛋白中酪蛋白约占80%,其中36%是β-酪蛋白。A_(2)β-酪蛋白和A_(2)β-酪蛋白是β-酪蛋白遗传变体中最常见的两种类型,A_(2)β-酪蛋白为天然原型。A_(2)β-酪蛋白和A_(2)β-酪蛋白消化酶解后会产生不同的生物活性肽,来源于A_(2)β-酪蛋白的BCM-7可能与1型糖尿病、心血管疾病、自闭症、精神分裂症、消化功能紊乱等人体慢性非传染性疾病的发生密切相关,A_(2)β-酪蛋白酶解后产生的BCM-7要比A_(2)β-酪蛋白少甚至不会产生β-酪啡肽-7(BCM-7)。β-酪蛋白基因多态性受常染色体上共显性基因控制,目前常用的检测方法为反相高效液相色谱法(RP-HPLC)、等电聚焦电泳(IEF)法和等位基因特异性聚合酶链式反应(AS-PCR)、单链构象多态性聚合酶链式反应(SSCP-PCR)等。文章对β-酪蛋白遗传变体A_(2)β-酪蛋白功能特点、遗传学特点及A_(2)β-酪蛋白基因检测方法进行综述,旨在为A_(2)β-酪蛋白应用于功能性食品,包括作为乳基料及添加到婴幼儿配方食品中的应用提供理论依据。

Casein accounts for about 80% of the total milk protein, of which 36% is β-casein. A_(2)β-casein and A_(2)β-casein are the two most common types of β-casein genetic variants, of which type A_(2)is the natural prototype. The digestion of A_(2)β-casein and A_(2)β-casein produces different bioactive peptides. BCM-7 derived from A_(2)β-casein may be closely related to the occurrence of type 1 diabetes, cardiovascular disease, autism, schizophrenia, digestive disorders and other chronic noncommunicable diseases in human body. The amount of BCM-7 produced by A_(2)β-casein after hydrolysis is less than that of A_(2)β-casein, or even no BCM-7. β-casein gene polymorphism is controlled by autosomal codominant genes. The most commonly used detection methods are RP-HPLC,IEF,AS-PCR and SSCP-PCR. In this paper, the functional characteristics, genetic characteristics and genotyping methods of A_(2)β-casein, the genetic variant of β-casein, A_(2)β-casein were reviewed in order to provide a theoretical basis for the application of A_(2)β-casein in functional food, including milk base and infant formula food.