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Despite their relatively poorly investigated phytochemistry, species of the genus Chuquiragaare widely commercialized. The present study reports the use of a high-resolution liquid chromatography–mass spectrometry-based metabolomics approach coupled with exploratory and supervised multivariate statistical analyses for species classification and chemical marker identification of four species of Chuquiraga(C. jussieui, C. weberbaueri, C. spinosa, and Chuquiragasp.) from Ecuador and Peru. Based on these analyses, a high percentage of correct classifications (87% to 100%) allowed the prediction of the taxonomic identity of Chuquiragaspecies. Through the metabolite selection process, several key constituents with the potential to be chemical markers were identified. Samples of C. jussieuidisplayed alkyl glycosides and triterpenoid glycosides as discriminating metabolites, while Chuquiragasp. displayed high concentrations of p-hydroxyacetophenone, p-hydroxyacetophenone 4-O-glucoside, p-hydroxyacetophenone 4-O-(6-O-apiosyl)-glucoside, and quinic acid ester derivatives as the main metabolites. Caffeic acid was characteristic for C. weberbauerisamples, whereas C. spinosadisplayed higher concentrations of the following new phenylpropanoid ester derivatives: 2-O-caffeoyl-4-hydroxypentanedioic acid (24), 2-O-p-coumaroyl-4-hydroxypentanedioic acid (34), 2-O-feruloyl-4-hydroxypentanedioic acid (46), 2,4-O-dicaffeoylpentanedioic acid (71), and 2-O-caffeoyl-4-O-feruloylpentanedioic acid (77).

We developed a simple methodology for labeling sulfated glycosaminoglycans (GAGs) in adult Drosophila melanogaster and studied some aspects of the biosynthesis and metabolism of these polymers during development. Adult D. melanogaster flies were fed with Na235SO4 for 72 h. During this period, 35S-sulfate was incorporated into males and females and used to synthesize 35S-sulfate–heparan sulfate (HS) and 35S-sulfate–chondroitin sulfate (CS). The incorporation of 35S-sulfate into HS was higher when compared to CS. In a pulse-chase experiment, we observed that 35S-sulfate incorporated into adult female was recovered in embryos and used for the synthesis of new 35S-sulfate-GAGs after 2 h of embryonic development. The synthesis of CS was higher than that of HS, indicating a change in the metabolism of these glycans from adult to embryonic and larval stages. Analysis of the CS in embryonic and larval tissues revealed the occurrence of nonsulfated and 4-sulfated disaccharide units in embryos, L1 and L2. In L3, in addition to these disaccharides, we also detected significant amount of 6-sulfated units that are reported here for the first time. Immunohistochemical analysis indicated that HS and CS were present in nonequivalent structures in adult and larval stages of the fly. Overall, these results indicate that 35S-sulfate-precursors are transferred from adult to embryonic and larval tissues and used to assemble different morphological structures during development.