Rapid measurement and evaluation of the effect of drying conditions on harpagoside content in Harpagophytum procumbens (devil's claw) root

Joubert E. ; Manley M. ; Gray B.R. ; Schulz H. (2005)


The effect of drying conditions on harpagoside (HS) retention, as well as the use of near-infrared spectroscopy (NIRS) for rapid quantification of the iridoids, HS, and 8-ρ-coumaroyl harpagide (8ρCHG) and moisture, in dried Harpagophytum procumbens (devil's claw) root was investigated. HS retention was significantly (P < 0.05) lower in sun-dried samples as compared to tunnel-dried (60 °C, 30% relative humidity) and freeze-dried samples. The best retention of HS was obtained at 50 °C when evaluating tunnel drying at dry bulb temperatures of 40, 50, and 60 °C and 30% relative humidity. NIRS can effectively predict moisture content with a standard error of prediction (SEP) and correlation coefficient (r) of 0.24% and 0.99, respectively. The HS and 8ρCHG NIRS calibration models established for both iridoid glucosides can be used for screening purposes to get a semiquantitative classification of devil's claw roots (for HS: SEP = 0.236%, r = 0.64; for 8ρCHG: SEP = 0.048%, r = 0.73). © 2005 American Chemical Society.

Please refer to this item in SUNScholar by using the following persistent URL: http://hdl.handle.net/10019.1/10084
This item appears in the following collections: