title: Natural wax constituents of a supercritical fluid CO(2) extract from quince (Cydonia oblonga Mill.) pomace.
abstract: The chemical constituents of a lipophilic extract from quince (Cydonia oblonga Mill.), obtained by supercritical fluid CO(2) extraction of the dried fruit pomace were investigated. Solvent partition of quince wax with n-hexane or acetone yielded an insoluble (crystalline) and a soluble (oily) fraction. Both fractions were analyzed separately using gas chromatography/mass spectrometry (GC/MS). The insoluble fraction consisted of saturated n-aldehydes, n-alcohols and free n-alkanoic acids of carbon chain lengths between 22 and 32, with carbon chain lengths of 26 and 28 dominating. Also odd-numbered unbranched hydrocarbons, mainly C27, C29 and C31, were detected particularly in the acetone-insoluble fraction (total, 15.8%). By means of vacuum liquid chromatography, triterpenoic acids were separated from the hexane-insoluble matter and identified as a mixture of ursolic, oleanolic and betulinic acids. The major constituents of the hexane-soluble fraction were glycerides of linoleic [Δ(9,12), 18:2] and oleic [Δ(9), 18:1] acids, accompanied by free linoleic, oleic and palmitic acids (C16). Moreover β-sitosterol, Δ(5)-avenasterol as well as trace amounts of other sterols were assigned. Finally the carotenoids phytoene and phytofluene were identified and quantified by UV/vis and high-performance liquid chromatography/MS techniques, yielding 1.0 and 0.3% of the quince wax, respectively. It is anticipated that the complex of lipid constituents from quince wax may exert interesting biological activities, the elucidation of which awaits further studies.
authors.affiliation: WALA Heilmittel GmbH, Dorfstrasse 3, 73087, Bad Boll/Eckwälden, Germany.
authors.forename: Peter
authors.initials: P
authors.lastname: Lorenz
authors.forename: Melanie
authors.initials: M
authors.lastname: Berger
authors.forename: Julia
authors.initials: J
authors.lastname: Bertrams
authors.forename: Kristian
authors.initials: K
authors.lastname: Wende
authors.forename: Kristin
authors.initials: K
authors.lastname: Wenzel
authors.forename: Ulrike
authors.initials: U
authors.lastname: Lindequist
authors.forename: Ulrich
authors.initials: U
authors.lastname: Meyer
authors.forename: Florian C
authors.initials: FC
authors.lastname: Stintzing
mesh_terms: D000096:Acetone; D000438:Alcohols / Q000032:analysis; D000473:Alkanes / Q000032:analysis; D002338:Carotenoids / Q000032:analysis; D005591:Chemical Fractionation / Q000379:methods*; D005227:Fatty Acids / Q000032:analysis; D005638:Fruit / Q000737:chemistry*; D008401:Gas Chromatography-Mass Spectrometry / Q000379:methods; D006586:Hexanes; D019906:Nuclear Magnetic Resonance, Biomolecular; D010936:Plant Extracts / Q000032:analysis*; D027824:Rosaceae / Q000737:chemistry*; D012855:Sitosterols / Q000032:analysis; D014315:Triterpenes / Q000032:analysis; D014885:Waxes / Q000737:chemistry* / Q000302:isolation & purification
chemical_list: D000438:Alcohols; D000473:Alkanes; D005227:Fatty Acids; D006586:Hexanes; D010936:Plant Extracts; D012855:Sitosterols; D014315:Triterpenes; D014885:Waxes; D000096:Acetone; C026385:n-hexane; D002338:Carotenoids; C025473:gamma-sitosterol; C003140:phytofluene; C100185:(all-E) phytoene