title: Determination of major phenolic compounds in Echinacea spp. raw materials and finished products by high-performance liquid chromatography with ultraviolet detection: single-laboratory validation matrix extension.
abstract: A method previously validated to determine caftaric acid, chlorogenic acid, cynarin, echinacoside, and cichoric acid in echinacea raw materials has been successfully applied to dry extract and liquid tincture products in response to North American consumer needs. Single-laboratory validation was used to assess the repeatability, accuracy, selectivity, LOD, LOQ, analyte stability (ruggedness), and linearity of the method, with emphasis on finished products. Repeatability precision for each phenolic compound was between 1.04 and 5.65% RSD, with HorRat values between 0.30 and 1.39 for raw and dry extract finished products. HorRat values for tinctures were between 0.09 and 1.10. Accuracy of the method was determined through spike recovery studies. Recovery of each compound from raw material negative control (ginseng) was between 90 and 114%, while recovery from the finished product negative control (maltodextrin and magnesium stearate) was between 97 and 103%. A study was conducted to determine if cichoric acid, a major phenolic component of Echinacea purpurea (L.) Moench and E. angustifolia DC, degrades during sample preparation (extraction) and HPLC analysis. No significant degradation was observed over an extended testing period using the validated method.
authors.affiliation: British Columbia Institute of Technology, 3700 Willingdon Ave, Burnaby, BC V5G 3H2, Canada. paula_brown@bcit.ca
authors.forename: Paula N
authors.initials: PN
authors.lastname: Brown
authors.forename: Michael
authors.initials: M
authors.lastname: Chan
authors.forename: Lori
authors.initials: L
authors.lastname: Paley
authors.forename: Joseph M
authors.initials: JM
authors.lastname: Betz
mesh_terms: D000465:Algorithms; D001205:Ascorbic Acid / Q000032:analysis; D002109:Caffeic Acids / Q000737:chemistry; D002138:Calibration; D002214:Capsules; D002726:Chlorogenic Acid / Q000032:analysis; D002851:Chromatography, High Pressure Liquid; D002934:Cinnamates / Q000032:analysis; D020900:Echinacea / Q000737:chemistry*; D035264:Flowers / Q000737:chemistry; D007202:Indicators and Reagents; D010636:Phenols / Q000032:analysis*; D010936:Plant Extracts / Q000032:analysis; D018515:Plant Leaves / Q000737:chemistry; D018517:Plant Roots / Q000737:chemistry; D018547:Plant Stems / Q000737:chemistry; D012015:Reference Standards; D015203:Reproducibility of Results; D012996:Solutions / Q000737:chemistry; D012997:Solvents; D013056:Spectrophotometry, Ultraviolet; D013386:Succinates / Q000737:chemistry; D015032:Zinc / Q000032:analysis
chemical_list: D002109:Caffeic Acids; D002214:Capsules; D002934:Cinnamates; D007202:Indicators and Reagents; D010636:Phenols; D010936:Plant Extracts; D012996:Solutions; D012997:Solvents; D013386:Succinates; D002726:Chlorogenic Acid; C100257:cynarine; D015032:Zinc; D001205:Ascorbic Acid; C100435:chicoric acid; C515101:caftaric acid