Phytochemical Characterization and Biological Assessment of Geranium robertianum L. Ethanolic Extract on Human Salivary Gland Carcinoma Cells

<i>Geranium robertianum</i> L. is used in traditional medicine to treat different systemic disorders and holds great therapeutic potential but remains understudied. To this aim, an ethanolic extract obtained from the aerial parts of <i>G. robertianum</i> L. (GR) was investigated in terms of phytochemical composition and biological activity. GR extract exhibited high levels of phenolic compounds and flavonoids. The antioxidant activity was determined by means of three different colorimetric assays (DPPH, ABTS, and FRAP), and the results obtained indicate that the ABTS assay showed the highest antioxidant capacity. Metal analysis was also performed. Fe was found to be the most abundant element in the analyzed extract, with a concentration of 363.65 ± 4.18 μg/g, followed by Zn, Mn, Ni, and Cr. Four potentially hazardous heavy metals, As, Co, Pb, and Cd, were found to be under the detection limit. The GR extract exhibited moderate antibacterial activity against both Gram-positive and Gram-negative bacteria, with inhibition zones generally comparable to those of levofloxacin. However, the extract was significantly less effective against the <i>P. aeruginosa</i> strain. On A253 human salivary gland carcinoma cells, GR extract elicited a dose-dependent antiproliferative effect, produced morphological changes, and increased ROS and both caspase-3/7 and caspase-9 levels.