Alkaloid profiles of Mimosa tenuiflora and associated methods of analysis.

Abstract

Abstract The alkaloid contents of the leaves and seeds of M. tenuiflora collected from northeastern Brazil were studied. Alkaloids were isolated by classical acid/base extraction procedures and by cation exchange solid phase extraction. The crude alkaloid fractions were then analysed by thin layer chromatography (TLC), gas chromatography-mass spectrometry (GC-MS) and liquid chromatography-mass spectrometry (LC-MS). In the initial analysis by GC-MS, two major alkaloids were detected and were identified as N,N-dimethyltryptamine (DMT) and 2-methylcarboline. A third alkaloid was only detected when extraction by method A was conducted. TLC analysis of the extracts also showed the presence of two major alkaloids. DMT and 2-methylcarboline were detected following GC-MS analysis. LC/UV/MS detected five alkaloids with UV and MS data consistent with tryptamine type alkaloids. These included DMT and 2-methylcarboline, and three unknown alkaloids. At least three possible minor alkaloids were detected, but their UV spectra was not consistent with the tryptamine type alkaloids. The presence of a possible artifact alkaloid was observed by LC-UV-MS analysis when extracts were prepared using extraction method A. Seed and leaf samples collected at different years were extracted and analysed by TLC and LC-MS. Significant differences were observed in the alkaloid profiles between seed and leaves in that the two major spots in the TLC chromatograms were absent in seed samples. The best method of analysis appeared to be solid phase extraction followed by LC/UV/MS.