Comparative study of morphological and anatomical features of Bidens L. Species

Introduction. Determining closely related impure species when confirming the authenticity of medicinal plant raw materials (mprms) is a very difficult and controversial task, especially for crushed and powdered mprms. One of such objects is the three-part beggarticks, which is prone to polymorphism and occupies the same area with the nodding beggarticks, the Spanish needles and the devil's beggarticks. Objective: to conduct a comparative pharmacognostic analysis of species of the genus Bidens L., which can be collected together with the pharmacopoeial species – three-part beggarticks. Material and methods. The objects of study were dried herbs of three-part beggarticks (Bidens tripartita L.), nodding beggarticks (Bidens cernua L.), Spanish needles (Bidens bipinnata L.), and devil's beggarticks (Bidens frondosa L.), collected in the Moscow region in 2020–2021. In this work, we studied the anatomical and morphological structure of leaves, as the most preferred part from a diagnostic point of view. The study of anatomical and morphological characteristics was carried out in accordance with the General Pharmacopoeial Monograph of the Russian Federation State Pharmacopoeia XIV 1.5.1.0003.15 “Leaves”. Results. A comparative description of the anatomical-diagnostic external and microscopic characteristics of the Bidens leaves has been obtained. Bidens tripartita and Bidens frondosa are higher than others. In contrast to the impure species, the Bidens tripartita has the largest deeply trifid, irregular serrated leaves, more pronounced tortuosity of the epidermal cells of the upper side of the leaf, multicellular thin-walled caterpillar-like and simple thick-walled hairs are combined, and the secretory canals in the mesophyll located along the vein. Conclusion. Among the studied Bidens species, each has characteristic features of its morphological and anatomical structure. These specific features can be used to establish the authenticity of the mprms and distinguish it from impure Bidens species, which require further research.