Pharmacognostic evaluation of bitter melon from Brazilian Northeast (Momordica charantia L.): identification of Momordicin II

Abstract

Objectives: To perform a pharmacognostic evaluation of bitter melon from Brazilian northeast (Momordica charantia L.) Methods: The botanical materials used consisted of leaves of Momordica charantia L., microcarpa and macrocarpa varieties collected in the period of flowering and fruiting. For the collection of the leaves was used pruning shears and for herborization were followed the usual procedures in this type of collection. The studies were carried out with the fresh leaves of these two varieties of Momordica charantia L to do the macro and micro morphological analysis. Results: the micro morphological analysis showed that the main differential parameter is that in the macrocarpa variety the trichomes are less frequent and are of the short multicellular type with 3 to 5 cells, whereas the microcarpa variety the trichomes are of the long multicellular type with 7 to 11 cells. The phytochemical approach has shown that the two varieties have in common alkaloids, steroids, triterpenoids, flavonoids, saponins, phenolic compounds, condensed tannins and flavonoids. Conclusion: Momordicin II (C36H58O9) was isolated and identified in the microcarpa variety by means of 1H-NMR and 13C-NMR and 2D structure similar to that found in the variety of Asian origin.