Exploring Anatomical and Chemical Markers to Characterize and Differentiate Among Bidens Species

Bidens pilosa L., Bidens alba (L.) DC., and Bidens subalternans DC., Asteraceae, are often misidentified because of their morphological similarities. The present study provides a comparative analysis of the morpho-anatomical characteristics, histochemical, and chemical fingerprints obtained by liquid chromatography mass spectrometry for these three species. Light microscopy, field emission scanning electron microscopy, and energy-dispersive X-ray spectroscopy were used to characterize diagnostic structures. Histochemical assays and LC-MS were applied to obtain chemical information from leaf, stem, and root extracts, and multivariate chemometrics including principal component analysis were used to classify the datasets. The morpho-anatomical and histochemical analysis allowed the identification and differentiation of the three species; also, the LC-MS analysis revealed that the main compounds in Bidens extracts are phenolics, and using chemometrics methods was possible to discriminate by species and plant parts. Together, these complementary approaches provide a robust basis for distinguishing closely related Bidens species and support more reliable pharmacognostic identification.