Pharmacobotanical study of the leaf and stem of Mikania lanuginosa for its quality control

Mikania lanuginosa DC, Asteraceae, is popularly known as "cipó-cabeludo" in Brazil due to a remarkable number of trichomes on its leaves and stems. It shows antimicrobial activity against Staphylococcus aureus, S. epidermidis and Bacillus cereus. This species can be confused with M. microlepis Baker and M. hirsutissima DC for substitution and tampering purposes. The aim of this study was to investigate the morpho-anatomy of leaf and stem of M. lanuginosa to obtain pharmacobotanical data that may contribute to its identification and taxonomic definition from other species of Mikania. The leaves and stems were investigated using scanning electron microscopy and light microscopy techniques. Mikania lanuginosa shows a uniseriate epidermis covered by a thin and smooth cuticle. The epidermal cells present sinuous anticlinal walls on both sides and anomocytic stomata were observed. A few glandular trichomes and numerous non-glandular trichomes were identified on both surfaces. The mesophyll is dorsiventral, the midrib has a biconvex contour and the petiole shows a circular shape in a cross-section. The stem has a circular shape. These pharmacobotanical features described for M. lanuginosa support data for its identification and taxonomic delimitation from other Mikania species, and are a contribution for the quality control of herbal drugs