title: Rapid and non-destructive determination of the echinacoside content in Echinacea roots by ATR-IR and NIR spectroscopy.
abstract: NIR reflection and ATR-IR spectroscopy methods are developed to determine the echinacoside content in roots of Echinacea angustifolia and Echinacea pallida. Based on the recorded spectra and the HPLC reference data, chemometrical analyses are performed using a partial least squares (PLS) algorithm. Generally, good calibration statistics are obtained for the prediction of the echinacoside content presenting comparatively high coefficients of determination (R(2)) and low root mean standard errors of cross validation (RMSECV). It is demonstrated that optimal predictions are possible when using a dispersive spectrometer covering the spectral range from 1,100 to 2,500 nm. In contrast to the time-consuming HPLC method, the described non-destructive measurements allow us to predict the echinacoside content already after an analysis time of approx. one minute. Both spectroscopic techniques presented in this paper are shown to be useful in agricultural practice as well as in the phytopharmaceutical industry.
authors.affiliation: Federal Centre for Breeding Research on Cultivated Plants, Institute for Plant Analysis, Quedlinburg, Germany. H.Schulz@bafz.de
authors.forename: Hartwig
authors.initials: H
authors.lastname: Schulz
authors.forename: Sven
authors.initials: S
authors.lastname: Pfeffer
authors.forename: Rolf
authors.initials: R
authors.lastname: Quilitzsch
authors.forename: Boris
authors.initials: B
authors.lastname: Steuer
authors.forename: Klaus
authors.initials: K
authors.lastname: Reif
mesh_terms: D002851:Chromatography, High Pressure Liquid; D020900:Echinacea / Q000737:chemistry*; D006027:Glycosides / Q000032:analysis*; D006801:Humans; D008517:Phytotherapy; D018517:Plant Roots; D013055:Spectrophotometry, Infrared / Q000379:methods; D019265:Spectroscopy, Near-Infrared / Q000379:methods
chemical_list: D006027:Glycosides; C060297:echinacoside