ABSTRACT
Tabernaemontana alba and Tabernaemontana arborea are Apocynaceae species used in Mexican traditional medicine for which little phytochemical information exists. In this study, preliminary gas chromatography/mass spectrometry analyses of different organs obtained from wild plants of both species identified a total of 10 monoterpenoid indole alkaloids (MIAs) and one simple indole alkaloid, nine of which were reported for the first time in these species. Furthermore, callus cultures were established from T. alba leaf explants and regeneration of whole plants was accomplished via somatic embryogenesis. The anti-addictive MIAs ibogaine and voacangine were then quantified by gas chromatography with flame ionization detection in wild plants of both species, as well as greenhouse-grown plants, in vitro-grown plantlets and embryogenic callus of T. alba. Ibogaine and voacangine were present in most samples taken from the whole plants of both species, with stem and root barks showing the highest concentrations. No alkaloids were detected in callus samples. It was concluded that T. alba and T. arborea are potentially viable sources of ibogaine and voacangine, and that these MIAs can be produced through somatic embryogenesis and whole plant regeneration of T. alba. Approaches to increase MIA yields in whole plants and to achieve alkaloid production directly in cell cultures are discussed.
Subject(s)
Ibogaine/analogs & derivatives , Ibogaine/analysis , Tabernaemontana/chemistry , Ibogaine/biosynthesis , Mexico , Species SpecificityABSTRACT
The 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced edema model in mice determined the anti-inflammatory activities in vivo of argentatins A, B and D, the main cycloartenol-type triterpenes present in Parthenium argentatum. Our results showed that argentatin B (ED50=1.5×10(-4)mmol/ear) and argentatin A (ED50=2.8×10(-4)mmol/ear) were more potent anti-inflammatory agents than indomethacin (ED50=4.5×10(-4)mmol/ear), the reference drug. Based on these findings, we decided to evaluate 13 derivatives of argentatins A and B. All the derivatives showed anti-inflammatory activity in the TPA-induced edema model in mice. The most active compound was 25-nor-cycloart-3, 16-dione-17-en-24-oic acid, obtained from argentatin A (ED50=1.4×10(-4)mmol/ear). Argentatin B was assayed as inhibitor of COX-2 activity one of the key enzymes involved in the TPA assay. The results showed that argentatin B at 15µM doses inhibited 77% COX-2 activity. Docking studies suggest that argentatin B interacts with Arg 120, a key residue for COX-2 activity.
Subject(s)
Anti-Inflammatory Agents/chemical synthesis , Asteraceae/chemistry , Terpenes/chemistry , Animals , Anti-Inflammatory Agents/pharmacology , Anti-Inflammatory Agents/therapeutic use , Asteraceae/metabolism , Binding Sites , Cell Line , Cell Survival/drug effects , Cyclooxygenase 2/chemistry , Cyclooxygenase 2/metabolism , Cyclooxygenase 2 Inhibitors/chemistry , Cyclooxygenase 2 Inhibitors/metabolism , Edema/chemically induced , Edema/drug therapy , Macrophages/cytology , Macrophages/drug effects , Macrophages/metabolism , Male , Mice , Molecular Docking Simulation , Nitric Oxide/metabolism , Protein Structure, Tertiary , Terpenes/isolation & purification , Terpenes/therapeutic use , Tetradecanoylphorbol Acetate/toxicity , Triterpenes/chemistry , Triterpenes/isolation & purification , Triterpenes/therapeutic useABSTRACT
In this work, the results of a study comparing the use of irradiation from different regions of the infrared spectrum for the promotion of several organic reactions, are presented and discussed. This use of eco-conditions provides a green approach to chemical synthesis. A set of ten different organic reactions were evaluated, including the Knoevenagel, Hantzsch, Biginelli and Meldrum reactions. It is important to highlight the use of a commercial device that produces infrared irradiation in the near infrared region and its distribution by convection providing heating uniformity, significantly reducing reaction times, achieving good yields and proceeding in the absence of solvent. It is also worth noting that a variety of different reactions may be performed at the same time. Finally, the products obtained were identified using TLC, together with corresponding MS-data, complementarily in comparison of NMR (1)H and (13)C data with literature information.
