Phenolic profile, antioxidant, anti-inflammatory and cytotoxic activities of endemic Plantago reniformis G. Beck

The present study was designed to define the phenolic profile, antioxidant, anti-inflammatory and cytotoxic activity of edible Plantago reniformis G. Beck, an endemic species which has never been comprehensively investigated before. The presence and content of 44 phenolics in methanol extract were studied using LC-MS/MS, where 31 compounds were found, the most dominant being: vanillic, chlorogenic, p-hydroxybenzoic, caffeic and p-coumaric acid, apigenin, luteolin and hyperoside. The antioxidant activity of the extract was determined through several assays. The extract showed moderate antioxidant activity in comparison to butylated hydroxyanisole (BHA), a well-known synthetic antioxidant. Anti-inflammatory potential was studied by means of cyclooxygenase-1 (COX-1) and 12-lipoxygenase (12-LOX) inhibitory activity, where P. reniformis showed sufficient ability to inhibit both enzymes (IC50 = 5.5 and 3.2 mg/mL, respectively). Treatment of three cancer cell lines resulted in a considerable dose-dependent inhibition of cell growth, where P. reniformis exerted a strong effect against cervix epitheloid carcinoma (HeLa) and breast adenocarcinoma (MCF7) cells, by reaching IC50 values at concentrations of 0.44 and 0.18 mg/mL, respectively. To conclude, these results support use of this species as a functional food and point to the desirability of examining endemic species, which could be potent sources of health-beneficial phytochemicals.