Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 6/27/2003
Publication Date: 9/28/2003
Citation: Seitz, L.M., Ram, M.S. 2003. Free tryptophan in wheat grain and milling fractions. Program Book of the 88th AACC Annual Meeting. p. 111. Meeting Abstract. Interpretive Summary: Abstract for the AACC Meeting to be held September 28 - October 2, 2003, in Portland, OR.
Technical Abstract: Relatively little information is available on free amino acids in whole wheat or milling fractions. In this research we focused on the essential amino acid tryptophan which we found could be readily extracted with methanol from ground whole wheat and wheat milling fractions. Extracts were analyzed by high performance liquid chromatography using UV-Vis and fluorescence detectors. Retention time and spectra (UV-Vis and fluorescence) of the component from samples were equivalent to those from a tryptophan standard. Derivatization with danzyl choride and ninhydrin also aided identification. From analysis of methanol extracts of ground wheat, tryptophan concentrations were about 12 and 35 micrograms/gram for cultivars Scout66 and Trego, respectively, grown near Bushland, TX, in 2002. Germination of these cultivars for about three days increased the tryptophan concentration slightly. With milling fractions, free tryptophan was present in bran and shorts at levels about 10 times higher than in flour. Analyses for free tryptophan in selected cultivars from known locations could provide information on factors such as type of wheat and environment during grain maturation that may influence the level of this important amino acid in wheat grain.