The current study aimed to evaluate the phytochemical profiles and antibacterial activity of the methanolic extracts from Biden pilosa L. and Biden bipinnata L. using gas chromatography-mass spectrometry (GC-MS) and high-performance liquid chromatography (HPLC). The plant parts, leaves, stems, roots, and flowers of both species were collected from natural habitats, dried in the shade, and extracted with methanol under controlled laboratory conditions. The GC-MS analysis detected an extensive range of bioactive compounds, which include flavonoids, alkaloids, phenolic compounds, and their derivatives, with significant qualitative and quantitative differences between plant parts and the species. The key phenolic and flavonoid compounds were verified by an HPLC chromatogram, establishing a distinct chemical fingerprint for every species. The agar well diffusion method was used to assess the extract antibacterial properties against both the Gram-positive and Gram-negative bacteria. The methanolic extract of Biden pilosa, especially from leaves and flowers, revealed stronger antibacterial activity than that of , analyze the mechanism of action, to evaluate their therapeutic value for the formulation of plant-Biden bipinnata. The combined action of several phytoconstituents, is detected by chromatographic analysis, is responsible for the observed bioactivity.  These gaps suggest that the Bidens species are a valuable source of natural antibacterial compounds. Further studies are required to isolate particular bioactive constituents of antimicrobial agents.

Keywords: Bidens pilosa, Bidens bipinnata, antibacterial activity, phytochemical profiling, methanolic extract, GC-MS, HPLC