Antioxidant Properties of Primula vulgaris Flower Extract and Its Cytotoxic Effect on Human Cancer Cell Lines

Primula vulgaris is a plant belonging to Primula genus, and these species are often used in traditional therapy. Although there are numerous studies on the antioxidant and cytotoxic effects of different Primula species, there are limited studies of these properties of P. vulgaris extracts. The aim of this study was to determine the antioxidant properties and cytotoxic effects of the extract prepared with dimethyl sulfoxide from P. vulgaris flowers. The total phenolic content, total flavonoid content, and reducing antioxidant power of the extract were determined using spectrophotometric methods. The cytotoxic effect of the extract on human colon (WiDr), lung (A549), liver (HepG2), breast (MCF-7), and prostate (PC-3) cancer cells and a normal human fibroblast cell line was assessed using the MTT assay. Total phenolic content and reducing power values of extract were found 33.02 +/- 0.92 mg gallic acid equivalents, and 64.86 +/- 1.18 mg trolox equivalents per g sample, respectively. Extract exhibited selective cytotoxic effect on all studied cancer cells compared to normal fibroblast cells, and the IC50 values of the extract in the cancer cell lines range from 191.8 to 375.3 mu g/mL. This work is one of the pioneering work that reveals the powerful antioxidant properties of P. vulgaris flower extract and its selective cytotoxic effect on cancer cell lines. Further studies are needed to identify the active molecules in the extract and the cytotoxic action mechanisms of these molecules.