title: Methods for the quantitation of human milk oligosaccharides in bacterial fermentation by mass spectrometry.
abstract: Oligosaccharides are the third most abundant component in human milk. In the past decades, it became apparent that they would be able to protect against pathogens and participate in the development of the gut microflora for infants. However, their role in infants' nutrition and development remains poorly understood. To better understand this function, it is extremely important to have a quantitative tool for profiling oligosaccharides. In this article, we show the development of a method to quantitatively differentiate the relative amounts of oligosaccharides fermented by different intestinal bacteria. To determine the oligosaccharide consumption, bacteria were grown in a medium using human milk oligosaccharides (HMOs) as the only carbon source purified from breast milk and further analyzed by matrix-assisted laser desorption/ionization-Fourier transform ion cyclotron resonance mass spectrometry (MALDI-FTICR MS). A method using an internal deuterium-labeled standard was developed and compared with an external standard method, with the internal standard method giving better precision and unambiguous measurements than the external standard method and providing to be a novel and robust tool for following bacterial fermentation of milk oligosaccharides.
authors.affiliation: Department of Chemistry and Biochemistry, School of Medicine, University of California, Davis, CA 95616, USA.
authors.forename: Milady R
authors.initials: MR
authors.lastname: Ninonuevo
authors.forename: Robert E
authors.initials: RE
authors.lastname: Ward
authors.forename: Riccardo G
authors.initials: RG
authors.lastname: LoCascio
authors.forename: J Bruce
authors.initials: JB
authors.lastname: German
authors.forename: Samara L
authors.initials: SL
authors.lastname: Freeman
authors.forename: Mariana
authors.initials: M
authors.lastname: Barboza
authors.forename: David A
authors.initials: DA
authors.lastname: Mills
authors.forename: Carlito B
authors.initials: CB
authors.lastname: Lebrilla
mesh_terms: D018407:Bacterial Physiological Phenomena; D001644:Bifidobacterium / Q000502:physiology; D002851:Chromatography, High Pressure Liquid; D005285:Fermentation; D013058:Mass Spectrometry / Q000379:methods; D017784:Milk Banks; D008895:Milk, Human / Q000737:chemistry*; D009844:Oligosaccharides / Q000032:analysis* / Q000737:chemistry / Q000302:isolation & purification; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / Q000379:methods; D017550:Spectroscopy, Fourier Transform Infrared / Q000379:methods; D014481:United States
chemical_list: D009844:Oligosaccharides