Cloetens L, Panee J, Åkesson B
Lund University Biomedical Nutrition, Pure and Applied Biochemistry, Centre for Applied Life Sciences Lund Sweden lieselotte.cloetens@tbiokem.lth.se.
Cell Mol Biol (Noisy-le-grand). 2013 Nov 3;59(1):43-57.
Milk contains a wide array of compounds with established or putative pro- or anti-oxidant function. The functions of these compounds have been intensively studied. This review focusses on some important aspects in this wide field namely the methodology for measurement of the total antioxidant capacity (TAC), the content of TAC and some related compounds in human and animal milks and infant formulas, and the effect of milk intake on antioxidant status in the body and on the activity of dietary flavonoids as studied in vitro and in vivo. Regarding methodology TAC in milk can be measured by spectrophotometric and electrochemical methods and some of their characteristics are reviewed. Milk, whey, high-molecular-weight and low-molecular-weight (LMW) fractions of whey have all been found to have antioxidant capacity using these techniques. The major antioxidant in the LMW fraction has been identified as urate. An extensive literature survey was made regarding data on the antioxidant capacity and related variables of milk obtained from different sources (human milk, infant formulas and animal milk) and subjected to different treatments. Differences in TAC between milks from different sources have been observed but due to the variety of techniques used no clear pattern is evident at present. Another important aspect is the putative effects of the intake of milk products on the antioxidant status of the consumer. A few studies performed in adults and premature infants are reviewed and it is stated that too little information is available to make any firm conclusions in this regard. Finally, a high interest has been devoted to the possible interference of milk with the antioxidant properties of flavonoid-rich food like tea. Most in vitro studies show an inhibition by milk on tea flavonoid activity whereas the results from the corresponding in vivo studies are equivocal. Our general conclusion is that several compounds in various milk fractions contribute to the antioxidant capacity of milk and that much further work is needed to unravel the complex interactions among the pro- and antioxidants, and their putative health effects on the consumer.
牛奶含有大量具有已确定或推测的促氧化或抗氧化功能的化合物。这些化合物的功能已得到深入研究。本综述聚焦于这一广泛领域的一些重要方面，即总抗氧化能力（TAC）的测量方法、人乳、动物乳和婴儿配方奶粉中TAC及一些相关化合物的含量，以及摄入牛奶对体内抗氧化状态和膳食类黄酮活性的影响（体外和体内研究）。关于测量方法，牛奶中的TAC可通过分光光度法和电化学方法进行测量，并对其一些特性进行了综述。使用这些技术发现，牛奶、乳清、乳清的高分子量和低分子量（LMW）组分均具有抗氧化能力。LMW组分中的主要抗氧化剂已被鉴定为尿酸盐。针对从不同来源（人乳、婴儿配方奶粉和动物乳）获得并经过不同处理的牛奶的抗氧化能力及相关变量的数据进行了广泛的文献调查。已观察到不同来源牛奶之间TAC存在差异，但由于使用的技术种类繁多，目前尚无明显的清晰模式。另一个重要方面是摄入乳制品对消费者抗氧化状态的推测影响。对在成年人和早产儿中进行的一些研究进行了综述，并指出在这方面可获得的信息太少，无法得出任何确凿结论。最后，人们对牛奶可能干扰富含类黄酮食物（如茶）的抗氧化特性高度关注。大多数体外研究表明牛奶会抑制茶类黄酮活性，而相应的体内研究结果则不明确。我们的总体结论是，各种牛奶组分中的几种化合物有助于牛奶的抗氧化能力，并且需要进一步开展大量工作来阐明促氧化剂和抗氧化剂之间的复杂相互作用及其对消费者的潜在健康影响。
