A 1H NMR-based metabolomic approach to study the production of antimalarial compounds from Psiadia arguta leaves (pers.) voigt

Recent Advancement in NMR Based Plant Metabolomics: Techniques, Tools, and Analytical Approaches

Plant metabolomics, a rapidly advancing field within plant biology, is dedicated to comprehensively exploring the intricate array of small molecules in plant systems. This entails precisely gathering comprehensive chemical data, detecting numerous metabolites, and ensuring accurate molecular identification. Nuclear magnetic resonance (NMR) spectroscopy, with its detailed chemical insights, is crucial in obtaining metabolite profiles. Its widespread application spans various research disciplines, aiding in comprehending chemical reactions, kinetics, and molecule characterization. Biotechnological advancements have further expanded NMR's utility in metabolomics, particularly in identifying disease biomarkers across diverse fields such as agriculture, medicine, and pharmacology. This review covers the stages of NMR-based metabolomics, including historical aspects and limitations, with sample preparation, data acquisition, spectral processing, analysis, and their application parts.

Chemical and transcriptomic analyses of leaf trichomes from Cistus creticus subsp. creticus reveal the biosynthetic pathways of certain labdane-type diterpenoids and their acetylated forms

Labdane-related diterpenoids (LRDs), a subgroup of terpenoids, exhibit structural diversity and significant commercial and pharmacological potential. LRDs share the characteristic decalin-labdanic core structure that derives from the cycloisomerization of geranylgeranyl diphosphate (GGPP). Labdanes derive their name from the oleoresin known as 'Labdanum', 'Ladano', or 'Aladano', used since ancient Greek times. Acetylated labdanes, rarely identified in plants, are associated with enhanced biological activities. Chemical analysis of Cistus creticus subsp. creticus revealed labda-7,13(E)-dien-15-yl acetate and labda-7,13(E)-dien-15-ol as major constituents. In addition, novel labdanes such as cis-abienol, neoabienol, ent-copalol, and one as yet unidentified labdane-type diterpenoid were detected for the first time. These compounds exhibit developmental regulation, with higher accumulation observed in young leaves. Using RNA-sequencing (RNA-seq) analysis of young leaf trichomes, it was possible to identify, clone, and eventually functionally characterize labdane-type diterpenoid synthase (diTPS) genes, encoding proteins responsible for the production of labda-7,13(E)-dien-15-yl diphosphate (endo-7,13-CPP), labda-7,13(E)-dien-15-yl acetate, and labda-13(E)-ene-8α-ol-15-yl acetate. Moreover, the reconstitution of labda-7,13(E)-dien-15-yl acetate and labda-13(E)-ene-8α-ol-15-yl acetate production in yeast is presented. Finally, the accumulation of LRDs in different plant tissues showed a correlation with the expression profiles of the corresponding genes.

1H NMR profiling and chemometric analysis as an approach to predict the leishmanicidal activity of dichloromethane extracts from Lantana camara (L.)

The application of ¹H NMR spectroscopy and chemometrics for the analysis of extracts of Lantana camara is described. This approach allowed to predict the leishmanicidal activity of samples obtained at different harvest times from their ¹H NMR spectra. The anti-leishmanial activity of dichloromethane extracts obtained from the aerial parts of L. camara was measured using an in vitro assay. As the extracts displayed differences in their activity according to a one-way ANOVA analysis, their ¹H NMR spectra were subjected to multivariate analysis using exploratory (Principal Component Analysis (PCA) and Anova Simultaneous Component Analysis (ASCA)) and regression, (Partial Least Squares Regression to Latent Structures (PLS)) chemometrics methods. These analyses allowed to establish and characterize a predictive model capable of determining the anti-leishmanial activity of Lantana camara dichloromethane extracts from their ¹H NMR spectra. Figures of merit of the developed method are given as well. The identified chemical signals responsible for the iPLS calibration model corresponded to the presence of eicosane, caryophyllene oxide, β-ionone, tiglic acid, lantanilic acid, camaric acid, and lantadene B; the chemical markers. This study proposed a fast and simple method that avoids the need of using complex biological assays to predict the leishmanicidal activity of L. camara dichloromethane extracts.