Comparison of the Morphology, Anatomy, and Chemical Profile of Mikania glomerata and Mikania laevigata

Abstract Mikania glomerata and Mikania laevigata are medicinal plants popularly used in Brazil for colds and asthma. Although several studies report differences in their composition, they are frequently used indistinctly, which may be due to misidentification of the species or the plant part used. Herein, the chemical, anatomical, and morphological profiles of both species were evaluated, seeking to differentiate them. Due to the pattern of secondary metabolites found in M. glomerata and M. laevigata, the chemical profile of the leaves was the characteristic that best differentiated the two species. Coumarin was present in all the leaf samples of M. laevigata but absent or in low concentration in leaf samples of M. glomerata. The stems presented coumarin in both species, albeit in different concentrations. The quantification of chlorogenic and dicaffeoylquinic acids was crucial for the separation of the two species, as higher concentrations are found in M. glomerata. The anatomic structure of the leaves, stem, and petioles of both species was conserved, even when exposed to different environments, but presented only subtle differences between species. The morphology of the leaves presented different characteristics for each species but altered when exposed to shade. Therefore, the chemical analysis together with the morphological characteristics of plants grown in full sunlight may be used for the correct identification of these species.