Martín-Ortiz A, Salcedo J, Barile D, Bunyatratchata A, Moreno F J, Martin-García I, Clemente A, Sanz M L, Ruiz-Matute A I
Instituto de Química Orgánica General (CSIC), Juan de la Cierva 3, 28006 Madrid, Spain.
Department of Food Science and Technology, University of California Davis, One Shields Avenue, Davis, CA 95616, USA.
J Chromatogr A. 2016 Jan 8;1428:143-53. doi: 10.1016/j.chroma.2015.09.060. Epub 2015 Sep 21.
A detailed qualitative and quantitative characterization of goat colostrum oligosaccharides (GCO) has been carried out for the first time. Defatted and deproteinized colostrum samples, previously treated by size exclusion chromatography (SEC) to remove lactose, were analyzed by nanoflow liquid chromatography-quadrupole-time of flight mass spectrometry (Nano-LC-Chip-Q-TOF MS). Up to 78 oligosaccharides containing hexose, hexosamine, fucose, N-acetylneuraminic acid or N-glycolylneuraminic acid monomeric units were identified in the samples, some of them detected for the first time in goat colostra. As a second step, a hydrophilic interaction liquid chromatography coupled to mass spectrometry (HILIC-MS) methodology was developed for the separation and quantitation of the main GCO, both acidic and neutral carbohydrates. Among other experimental chromatographic conditions, mobile phase additives and column temperature were evaluated in terms of retention time, resolution, peak width and symmetry of target carbohydrates. Narrow peaks (wh: 0.2-0.6min) and good symmetry (As: 0.8-1.4) were obtained for GCO using an acetonitrile:water gradient with 0.1% ammonium hydroxide at 40°C. These conditions were selected to quantify the main oligosaccharides in goat colostrum samples. Values ranging from 140 to 315mgL(-1) for neutral oligosaccharides and from 83 to 251mgL(-1) for acidic oligosaccharides were found. The combination of both techniques resulted to be useful to achieve a comprehensive characterization of GCO.
首次对山羊初乳寡糖（GCO）进行了详细的定性和定量表征。对脱脂和脱蛋白的初乳样品，先前通过尺寸排阻色谱（SEC）处理以去除乳糖，然后通过纳流液相色谱 - 四极杆 - 飞行时间质谱（Nano-LC-Chip-Q-TOF MS）进行分析。在样品中鉴定出多达78种含有己糖、己糖胺、岩藻糖、N-乙酰神经氨酸或N-糖基神经氨酸单体单元的寡糖，其中一些是首次在山羊初乳中检测到。第二步，开发了一种亲水相互作用液相色谱 - 质谱联用（HILIC-MS）方法，用于分离和定量主要的GCO，包括酸性和中性碳水化合物。在其他实验色谱条件中，根据目标碳水化合物的保留时间、分离度、峰宽和对称性对流动相添加剂和柱温进行了评估。使用乙腈：水梯度和0.1%氢氧化铵在40°C下，GCO获得了窄峰（wh：0.2 - 0.6分钟）和良好的对称性（As：0.8 - 1.4）。选择这些条件来定量山羊初乳样品中的主要寡糖。发现中性寡糖的值在140至315mgL(-1)之间，酸性寡糖的值在83至251mgL(-1)之间。这两种技术的结合对于全面表征GCO很有用。
