Chemical profiles and metabolite study of raw and processed Cistanche deserticola in rats by UPLC-Q-TOF-MS^E

Background: Chinese materia medica processing is a distinguished and unique pharmaceutical technique in Traditional Chinese Medicine (TCM) used for reducing side effects, and increasing or even changing therapeutic efficacy of the raw herbs.Changes in the essential components induced by an optimized processing procedure are primarily responsible for the increased efficacy of medicinal plants.The kidney-yang invigorating effect of rice wine-steamed Cistancha deserticola (C. deserticola) was stronger than raw C. deserticola (CD).

Methods: A comparison analysis was carried out using the UPLC-Q-TOF-MS^E with the UNIFI informatics platform to determine the influence of processing. In vitro studies were performed for the characterization of constituents as well as metabolites in vivo. The chemical components were determined in CD and its processed products. The multivariate statistical analyses were conducted to evaluate variations between them while OPLS-DA was used for pairwise comparison.

Results: The results of this study revealed considerable variations in phenylethanoid glycosides (PhGs) and iridoids after processing. A total of 97 compounds were detected in the extracts of CD and its processed product. PhGs having 4'-O-caffeoyl group in the 8-O-β-D-glucopyranosyl part, like acteoside, cistanoside C, campneoside II, osmanthuside decreased after being processed, while PhGs with 6'-O-caffeoyl group in the 8-O-β-D-glucopyranosyl part, such as isoacetoside, isocistanoside C, isocampneoside I, isomartynoside increased, especially in the CD-NP group. The intensity of echinacoside and cistanoside B whose structure possess 6'-O-β-D-glucopyranosyl moiety also increased. In in vivo study, 10 prototype components and 44 metabolites were detected in rat plasma, feces, and urine. The obtained results revealed that processing leads to the considerable variation in the chemical constituents of CD and affected the disposition of the compounds in vivo, and phase II metabolic processes are the key cascades of each compound and most of the metabolites are associated with echinacoside or acteoside.

Conclusions: This is the first global comparison research of raw and processed CD. These findings add to our understanding of the impact of CD processing and give important data for future efficacy investigations.