title: Separation of geometric isomers of native lutein diesters in marigold (Tagetes erecta L.) by high-performance liquid chromatography-mass spectrometry.
abstract: Lutein is found in many foods; the richest and purest plant source is marigold flower (Tagetes erecta L.). In this plant, lutein is in the form of saturated fatty acid diesters. By using a binary mobile phase consisting of ethyl acetate and acetonitrile-methanol (9:1), improved separation was achieved on a C18-bonded phase. The unique absorption of lutein cis isomers at 330nm was used in combination with MS to identify the novel cis-lutein isomeric dimyristate, myristate-palmitate, dipalmitate, and palmitate-stearate diesters, as well as the rare combinations of both trans- and cis-lutein laurate-palmitate and trans- and cis-lutein myristate-stearate. The presence of the all-trans-lutein laurate-myristate, dimyristate, myristate-palmitate, palmitate-stearate, and distearate diesters, reported by others, was also confirmed.
authors.affiliation: Food Research Program, Agriculture & Agri-Food Canada, Guelph, Ont, N1G 5C9 Canada. caor@agr.gc.ca
authors.forename: Rong
authors.initials: R
authors.lastname: Tsao
authors.forename: Raymond
authors.initials: R
authors.lastname: Yang
authors.forename: J Christopher
authors.initials: JC
authors.lastname: Young
authors.forename: Honghui
authors.initials: H
authors.lastname: Zhu
authors.forename: Tony
authors.initials: T
authors.lastname: Manolis
mesh_terms: D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D007536:Isomerism; D014975:Lutein / Q000737:chemistry / Q000302:isolation & purification*; D013058:Mass Spectrometry; D013056:Spectrophotometry, Ultraviolet; D031686:Tagetes / Q000737:chemistry*
chemical_list: D014975:Lutein