Ferreira I M P L V O
CEQUP/Serviço de Bromatologia, Faculdade de Farmácia da Universidade do Porto, R. Aníbal Cunha 164, 4050-047 Porto, Portugal.
Br J Nutr. 2003 Jul;90(1):127-33. doi: 10.1079/bjn2003882.
The composition of fourteen infant formulae and six follow-up milks with regard to their free amino acids (including taurine), free nucleotides, orotic acid, and free and total l-carnitine content was studied. The levels found were compared with the limits established in European legislation and with the composition of human and cows' milk samples. HPLC methodologies, optimized and validated for the matrices under study, were used, except for free and total l-carnitine contents that were quantified using a flow-injection manifold, also optimized and validated for the matrices under study. Global statistical treatment of the results by cluster analysis indicated similarities between the contents of the N compounds under study of infant formulae, follow-up milks and cows' milk and differences with regard to human milk composition. The principal component analysis showed that 60.2 % of the variation in data was due to the first principal component, and the second component represented 23.8 % of the total information. Nucleotide profiles, orotic acid, and free and total l-carnitine contents explain the main differences observed between human milk and the other milks studied (cows' milk, infant formulae and follow-up milks). Cows' milk is distinguished from infant formulae and follow-up milks mainly owing to the different uric acid contents and free amino acids profiles.
对14种婴儿配方奶粉和6种后续奶粉的游离氨基酸（包括牛磺酸）、游离核苷酸、乳清酸以及游离和总左旋肉碱含量的组成进行了研究。将所测得的含量与欧洲法规规定的限值以及人乳和牛乳样本的组成进行了比较。除了游离和总左旋肉碱含量采用流动注射系统进行定量分析（该系统也针对所研究的基质进行了优化和验证）外，其余均采用了针对所研究基质进行优化和验证的高效液相色谱法。通过聚类分析对结果进行整体统计处理，结果表明，所研究的婴儿配方奶粉、后续奶粉和牛乳中含氮化合物的含量具有相似性，而与人乳组成存在差异。主成分分析表明，数据变化的60.2%归因于第一主成分，第二主成分占总信息的23.8%。核苷酸谱、乳清酸以及游离和总左旋肉碱含量解释了人乳与所研究的其他奶类（牛乳、婴儿配方奶粉和后续奶粉）之间观察到的主要差异。牛乳与婴儿配方奶粉和后续奶粉的区别主要在于尿酸含量和游离氨基酸谱不同。
