Xi Gao,Yu Lu,Ming Wei,MeiFang Yang,CaiXia Zheng,Chengjian Wang,Ying Zhang,Linjuan Huang,Zhongfu Wang
The functional role of human milk oligosaccharides (HMOs) is closely associated with their type, composition, and structure. However, a detailed analysis of HMOs is difficult because neutral oligosaccharides (NHMOs) are mixed with sialylated oligosaccharides (SHMOs) in milk. Here, NHMOs were separated from SHMOs by DEAE-52 anion chromatography, and lactose was removed by graphite carbon solid-phase extraction. Lactose-free NHMOs were analyzed by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) based on Girard’s reagent P on-target derivatization (GPOD), and SHMOs were analyzed by MALDI-TOF-MS following selective sialic acid derivatization and GPOD. Sixty-four oligosaccharides were detected: 36 NHMOs, of which 28 were fucosylated, and 28 SHMOs, of which 8 with α-2,3-linked monosialic acid, 2 with α-2,3-linked disialic acid, 10 with α-2,6-linked monosialic acid, 2 with α-2,6-linked disialic acid, and 5 with both α-2,3- and α-2,6-linked disialic acid. These findings provide the groundwork for further characterization of the structure and activity of HMOs.
Huipeng Liu,Xiaoyu Wei,Shuyu Zu,Xihuang Lin,Jinchuang Zhang,Aimin Shi,Qiang Wang,Ning He
Plant-derived neutral oligosaccharides and pectic-oligosaccharides (POS) have been suggested as prebiotics based on their degree of polymerization (DP) and structural complexity. In the present study, neutral oligosaccharides without galacturonic acid were produced from commercial apple pectin using an optimized concentration of pectinase and degradation time. The crude oligosaccharide solution was refined by membrane separation using a DEAE-Sepharose CL-6B column, a graphite carbon column and an Xbridge C18 column, which resulted in the neutral oligosaccharides with DP 3–13. The monosaccharide composition of oligosaccharides primarily included glucose, arabinose, galactose and xylose without galacturonic acid. The structure of the oligosaccharides was analyzed using mass spectrometry with an electrospray ionization source by UPLC on an HILIC column and 1 H NMR. The MS/MS spectra in positive ion mode and 1 H NMR showed a main oligosaccharide structure corresponding to the connection of arabinogalactan with Galβ1→4Galβ1→4Galβ1→4Galβ1→α3Ara f . The growth of the selected Lactobacillus . strains was improved by adding refined neutral oligosaccharides with DP = 3–13 compared with commercial inulin , and growth of Escherichia coli had not basically grown. Therefore, neutral oligosaccharides (DP = 3–13) can be considered effective prebiotics for potential application in functional food.
危险品化学品经营许可证（带存储）