研究: 奶牛与水牛初乳中乳寡糖组分比较研究

乳寡糖是由乳汁中含量丰富的固体物质组成．研究结果表明，乳寡糖有提高免疫、益生元及抗感染等作用，已发现与婴儿肠道发育、神经智力发育等多方面关系密切．水牛奶是除牛奶外的第二大奶源，国际上公认其为营养含量高、口感好的优质乳制品，但目前针对水牛乳寡糖的研究多以美洲水牛为研究对象，尚无中国水牛的相关研究．本研究利用固相萃取对已脱脂和除去蛋白质的广西水牛初乳乳汁样品进行纯化，并采用苯胺 (aniline，Bn)衍生化试剂对其进行衍生化处理，通过UPLC-ESI-Q-TOF-MS液相质谱进行优化后，对水牛初乳中的寡糖组分进行测定并与牛乳进行了对比，最终测得奶牛初乳中19种及水牛初乳中的9种乳寡糖组分，并对二者的种类及含量进行比较，发现在两种初乳的乳寡糖中，中性糖二糖m/z 385.15和中性糖三糖m/z 547.21以及酸性糖m/z 635.23均为其主要寡糖成分，与其他乳寡糖相比含量相对较高．总体而言水牛初乳中的中性寡糖占比比奶牛初乳高，二者中性糖占乳寡糖总量的比例分别为88.88%和63.16%．

Research: Comparative Study on Milk Oligosaccharides in Buffalo and Cow Colostrum Milk

Milk oligosaccharides, which are free oligosaccharides in the mammalian milk, is one of the main composition in milk. Recent studies suggested that milk oligosaccharides improved immune function, and showed prebiotics as well as anti-infection actives. Milk oligosaccharides is also important for the intestinal development, neural development of infants. Buffalo (Bubalus bubalis) milk is the second important milk source besides cow milk. It was also well accepted that buffalo milk was rich in nutritional content and was a high quality dairy product with good taste. However, researches on buffalo milk oligosaccharides was limited and only worked on American buffalo. On the other hand, milk oligosaccharides on Chinese buffalo is lacking. In the present study, colostrum milk samples from Guangxi buffalo were purified with solid phase extraction and modified by Aniline (Bn) derivative reagent. The sample was further purified by UPLC-ESI-Q-TOF-MS. The oligosaccharide components in buffalo colostrum were determined and compared with the cow colostrum milk. 19 kinds of oligosaccharides were found in cow colostrum and 9 in buffalo colostrum. Moreover, in both two kinds of colostrum, neutral disaccharide m/z 385.15, neutral trisaccharide m/z 547.21 and acidic oligosaccharide m/z 635.23 were the main composition. In general, the proportion of neutral oligosaccharides in buffalo milk was higher than that in cow milk, with a ratio of 88.88% and 63.16%, respectively.