title: Stabilization of caffeic acid derivatives in Echinacea purpurea L. glycerin extract.
abstract: Recent work has shown that enzymatic degradation and oxidation of cichoric acid and other caffeic derivatives occurs in Echinacea preparations. However, very little is known as to the means of stabilizing these phytopreparations. To stabilize the glycerin extract of Echinacea purpurea, we have evaluated the effects of 3 natural antioxidants (citric acid, malic acid, and hibiscus extract) on the stability of the major caffeic acid derivatives (caftaric acid, caffeic acid, cichoric acid, and 2-O-feruloyl-tartaric acid). Chlorogenic acid, which normally occurs in an ethanol extract of E. purpurea, was not present in the glycerin extract. The caffeic acid derivatives, with the exception of 2-O-feruloyl-tartaric acid, were subject to degradation in the control sample. 2-O-Feruloyl-tartaric acid was stable during the whole testing period. All antioxidant treatments greatly improved the stability of caffeic acid derivatives. Stability was dependent upon the concentration of antioxidant added.
authors.affiliation: Tom's of Maine, 302 Lafayette Center, P.O. Box 710, Kennebunk, Maine 04043, USA. chantalb@Tomsofmaine.com
authors.forename: Chantal
authors.initials: C
authors.lastname: Bergeron
authors.forename: Stefan
authors.initials: S
authors.lastname: Gafner
authors.forename: Laura L
authors.initials: LL
authors.lastname: Batcha
authors.forename: Cindy K
authors.initials: CK
authors.lastname: Angerhofer
mesh_terms: D000975:Antioxidants / Q000494:pharmacology*; D002109:Caffeic Acids / Q000737:chemistry*; D002726:Chlorogenic Acid / Q000031:analogs & derivatives* / Q000737:chemistry; D002851:Chromatography, High Pressure Liquid; D019343:Citric Acid / Q000494:pharmacology; D004355:Drug Stability; D020900:Echinacea / Q000737:chemistry*; D005990:Glycerol; D008293:Malates / Q000494:pharmacology; D019660:Malvaceae / Q000737:chemistry; D010936:Plant Extracts / Q000737:chemistry*; D013386:Succinates; D013644:Tartrates / Q000737:chemistry
chemical_list: D000975:Antioxidants; D002109:Caffeic Acids; D008293:Malates; D010936:Plant Extracts; D013386:Succinates; D013644:Tartrates; D019343:Citric Acid; D002726:Chlorogenic Acid; C030298:malic acid; D005990:Glycerol; C100435:chicoric acid; C040048:caffeic acid