Stachys longiflora extract was prepared by ultrasonic extraction method. The phytochemicals in the extracts were analyzed by liquid chromatography-electrospray tandem mass spectrometry. The antibiofilm activity against Staphylococcus aureus ATCC 25923 was assessed using the MTT method and scanning electron microscopy. Also, the anticancer activity of the plant extract was evaluated on MCF-7 cells.

This study investigates the phytochemical profile, antibiofilm, and anticancer properties of the endemic Stachys longiflora. Phytochemical analysis is performed using liquid chromatography coupled with electrospray ionization tandem mass spectrometry, identifying 19 compounds, with verbascoside as the major component (12 290 ± 21 μg g⁻¹). The anticancer activity of the extract is assessed on MCF-7 breast cancer cells using the MTT assay. IC₅₀ value is determined to be 5 mg mL⁻¹. Oxidative stress parameters, including total oxidant and antioxidant status, along with inflammatory cytokine levels, are measured in cell lysates. The cytokines TNF-α, TGF-β, DEF-β, and IL-1β are found to be elevated in all treatment groups compared to the control. Antibiofilm activity against Staphylococcus aureus ATCC 25923 is evaluated using the MTT method and scanning electron microscopy. The minimum inhibitory concentration of the plant extract is determined to be 250 μg mL⁻¹. Biofilm inhibition and biofilm eradication increase in parallel with the concentration of the plant extract. At 2× MIC, biofilm inhibition and eradication are 74.37 ± 1.39% and 44.99 ± 1.03%, respectively. These findings highlight Stachys longiflora as a promising source of bioactive compounds with significant antibiofilm and anticancer properties.