Dereplication of phenolic derivatives of three Erythroxylum species using liquid chromatography coupled with ESI‐MSⁿ and HRESIMS

Abstract

Introduction: Given the diversity of secondary metabolites produced by species of the genus Erythroxylum, in addition to the many methods that have already been described in the literature, modern screening and identification methodologies, such as dereplication, represent an efficient and quick strategy compared to the classic techniques linked to natural product research. Objective: The objective of the present study was to determine the phenolic profiles obtained from three species of Erythroxylum (Erythroxylum pauferrense Plowman, Erythroxylum pulchrum A.St.-Hil. and Erythroxylum simonis Plowman) by dereplication using liquid chromatography coupled with ESI-MS n and HRESIMS. Material and Methods: Ethyl acetate and n-butanolic fractions from crude ethanolic extract of Erythroxylum species were analyzed by HPLC-ESI-MS n and HPLC-HRESIMS, in order to identify its corresponding compounds. Experiments were performed in negative ionization mode, and the metabolites were provisionally identified based on deprotonated molecules, molecular formulas, fragmentation patterns and literature data. The corresponding isolated compounds were characterized by 1 H and 13 C NMR spectroscopy.Results: According to the dereplication method, it was possible to establish and compare the phenolic profile of the corresponding species by the assignment of 55 compounds, most of which were first described in these species and among which some were also new to the Erytroxylum genus. Additionally, nine compounds were isolated, including biphenyl-3,3 0 ,4,4 0 -tetraol, where the mass spectral data were not sufficient for their identification, and reported for the first time in the Erythroxylaceae family. Conclusion: This research contributes to the phytochemical knowledge of theErythroxylum genus and demonstrates the importance of the dereplication method regarding the investigation of natural products, enabling accurate identification of the metabolites while avoiding the efforts and material expenses involved in the isolation of known compounds.

Characterization of Extracts of Coffee Leaves (Coffea arabica L.) by Spectroscopic and Chromatographic/Spectrometric Techniques

“…The ion at m / z 231 was generated by a second neutral loss of catechol (110 Da). Comparing the tandem mass spectrometry information with data previously published [ 39 , 40 , 41 ], the compounds 31a and 31b were identified as cinchonain I isomers ( Figure 8 ).…”

Dereplication of tropane alkaloids from four Erythroxylum species using liquid chromatography coupled with ESI‐MSn and HRESIMS

“…3,4 This genus is characterized by tropane alkaloids as the main phytochemical markers, although other classes of secondary metabolites, including flavonoids, phenolic acids, triterpenes and diterpenes, are common in the species. 5,6 Currently, a total of 383 compounds have been described in Erythroxylum species, the vast majority being tropane alkaloids, about 197 of these metabolites. 7 Great attention was given to the genus in the 19th century, with the species Erythroxylum coca Lam., due to the presence of cocaine, a tropanic alkaloid that has psychoactive action on the central nervous system and quickly develops dependence.…”

“…Erythroxylum species can be found in different biomes in Brazil, and 128 taxa have been catalogued, distributed from regions with closed and humid vegetation such as the Amazon forest to semiarid regions such as the caatinga, the latter grouping 78 species, 34 of which are endemic 3,4 . This genus is characterized by tropane alkaloids as the main phytochemical markers, although other classes of secondary metabolites, including flavonoids, phenolic acids, triterpenes and diterpenes, are common in the species 5,6 …”

Rapid profiling of potential antitumor polymethoxylated flavonoids in natural products by integrating cell biospecific extraction with neutral loss/diagnostic ion filtering‐based high‐performance liquid chromatography–quadrupole time‐of‐flight tandem mass spectrometry

“…After living cell biospecific extraction, HPLC–quadrupole time‐of‐flight–MS/MS (HPLC‐QTOF‐MS/MS) plays an increasingly critical role in the analysis and identification of bioactive compounds 17–19 . However, overwhelming amounts of MS datasets are generated, which makes manual data analysis challenging, especially for achieving MS information of low‐abundance compounds being overwhelmed by major compounds or background noise 20 . To facilitate and simplify post‐acquisition MS data processing, various data mining technologies have been developed with excellent resolution, high sensitivity, outstanding selectivity, and excellent accuracy, such as neutral loss filtering, diagnostic ion filtering, de novo identification, mass defect filtering, isotope pattern filtering, predicted compound screening, and database‐assisted peak annotation 21–24 .…”

“…[17][18][19] However, overwhelming amounts of MS datasets are generated, which makes manual data analysis challenging, especially for achieving MS information of low-abundance compounds being overwhelmed by major compounds or background noise. 20 To facilitate and simplify post-acquisition MS data processing, various data mining technologies have been developed with excellent resolution, high sensitivity, outstanding selectivity, and excellent accuracy, such as neutral loss filtering, diagnostic ion filtering, de novo identification, mass defect filtering, isotope pattern filtering, predicted compound screening, and database-assisted peak annotation. [21][22][23][24] To date, only strategies with PMF aglycone-oriented extraction and mass defect filtering have been established to screen PMFs in Citrus aurantium, Murraya paniculata, Murraya exotica, and C. reticulata Blanco, and their structures were identified by MS/MS spectra with diagnostic product ions.…”