Feruloyl dopamine-O-hexosides are efficient marker compounds as orthogonal validation for authentication of black cohosh (Actaea racemosa)—an UHPLC-HRAM-MS chemometrics study

Abstract

Due to the complexity and variation of the chemical constituents in authentic black cohosh (Actaea racemosa) and its potential adulterant species, an accurate and feasible method for black cohosh authentication is not easy. A high resolution accurate mass (HRAM) LC-MS fingerprinting method combined with chemometric approach was employed to discover new marker compounds. Seven hydroxycinnamic acid amide (HCAA) glycosides are proposed as potential marker compounds for differentiation of black cohosh from related species, including two Asian species (A. foetida, A. dahurica) and two American species (A. pachypoda, A. podocarpa). These markers were putatively identified by comparing their mass spectral fragmentation behavior with those of their authentic aglycone compounds and phytochemistry reports. Two isomers of feruloyl methyldopamine 4-O-hexoside ([M+H]+ 506) and one feruloyl tyramine 4-O-hexoside ([M+H]+ 476) contributed significantly to the separation of Asian species in principle component analysis (PCA) score plot. The efficacy of the models built on four reasonable combinations of these markers in differentiating black cohosh and its adulterants were evaluated and validated by partial least-square discriminant analysis (PLS-DA). Two models based on these reduced dataset achieved 100% accuracy based on the current sample collection, including the model that used only three feruloyl dopamine-O-hexoside isomers ([M+H]+ 492) and one feruloyl dopamine-O-dihexoside ([M+H-hexosyl]+ at m/z 492).

Glucosylation of the phytoalexin N‐feruloyl tyramine modulates the levels of pathogen‐responsive metabolites in Nicotiana benthamiana

“…It is assumed that its main function in plants is to strengthen the cell walls and therefore prevent the entry of pathogens into suberizing tissue. The biosynthesis of hydroxycinnamoyl amides has been well studied, but a UGT capable of glucosylating phytoalexins has not been reported to date, although glucosides of the amides have been frequently found (Yahagi et al ., ; Bolleddula et al ., ; Nikolić et al ., , ; Yang et al ., ; Yim et al ., ; Zhang et al ., ; Pei et al ., ; Geng et al ., ; Oliveira de Silva and Batista, ; Wang et al ., ). The biological function of glucosides of hydroxycinnamoyl amides is unclear but they might play a similar role like monolignol glucosides in plant defence (Le Roy et al ., ).…”

Selection and characterization of botanical natural products for research studies: a NaPDI center recommended approach

“…Thus, testing botanical natural products for adulteration is critical. Several research groups have used targeted 64,87,90,[111][112][113] or untargeted methods [114][115][116] to identify adulterants in botanical natural products. For example, we studied 35 commercial products listed as "goldenseal".…”

“…Untargeted metabolomics may serve as a useful tool for identifying unexpected contaminants. 29,111,115,127 However, it should be noted that untargeted methods are likely to have higher limits of detection than targeted methods; thus, the former may fail to detect low-level contaminants. Furthermore, some contaminants are detectable only with specialized analytical methods.…”

Detection of adulteration in Hydrastis canadensis (goldenseal) dietary supplements via untargeted mass spectrometry-based metabolomics

“…Though several targeted techniques have been used to find adulterants in dietary supplements [Simmler, 2017; Steuer, 2017], there has not yet been a study performed to detect adulteration in a sample set of commercial products, ostensibly derived from the same botanical, with an untargeted approach. Untargeted metabolomics approaches have been employed to discriminate between different botanical species as well as variations in the geographic origin of materials [Kang, 2008; Mncwangi, 2014], and studies adulterating pure botanical material have shown discriminating patterns that can be discerned using untargeted techniques [Dowlatabadi, 2017; Geng, 2015; Geng, 2017]. However, little attention has been paid to commercial botanical products, where neither the geographical provenance, cultivation conditions, nor the harvesting and production specifications are known.…”