title: Determination of amino acids in selenium-enriched yeast by gas chromatography-mass spectrometry after microwave assisted hydrolysis.
abstract: A simple, rapid microwave digestion procedure for protein hydrolysis preceding the determination of amino acids in yeast using gas chromatography-mass spectrometry (GC-MS) is described. Protein hydrolysis was performed in a focused microwave using 4M methanesulfonic acid (MAS). Amino acids were derivatized with methyl chlorofomate (MCF) and extracted into chloroform prior to GC-MS analysis. The microwave parameters, including power, temperature and heating time, were optimized. It was found that temperature and heating time were the most influential factors. A total of 17 amino acids were determined in selenium-enriched yeast with use of standard addition calibration. Limits of detection and quantitation (LODs/LOQs) of the amino acids measured were in the sub-nmol range, suitable for monitoring of amino acids in yeast and other food products.
authors.affiliation: National Research Council Canada, Ottawa, Ontario, Canada.
authors.forename: Xu
authors.initials: X
authors.lastname: Zhang
authors.forename: Lu
authors.initials: L
authors.lastname: Yang
authors.forename: Zoltan
authors.initials: Z
authors.lastname: Mester
mesh_terms: D000596:Amino Acids / Q000032:analysis*; D005561:Formates / Q000737:chemistry; D008401:Gas Chromatography-Mass Spectrometry / Q000295:instrumentation; D006868:Hydrolysis; D008872:Microwaves; D012643:Selenium / Q000737:chemistry*; D013696:Temperature; D013997:Time Factors; D015002:Yeast, Dried / Q000737:chemistry*
chemical_list: D000596:Amino Acids; D005561:Formates; D012643:Selenium; C014667:methyl chloroformate