Antioxidant, antimicrobial and anti-proliferative activities of Solanum tuberosum L. var. Vitelotte.

Solanum tuberosum L. var. Vitelotte is a potato variety widely used for human consumption. The pigments responsible for its attractive color belong to the class of anthocyanins. The objectives of this study were to characterize and measure the concentration of anthocyanins in pigmented potatoes and to evaluate their antioxidant and antimicrobial activities and their anti-proliferative effects in solid and hematological cancer cell lines. Anthocyanins exert anti-bacterial activity against different bacterial strains and a slight activity against three fungal strains. The Gram-positive bacterium Staphylococcus aureus and the fungus Rhyzoctonia solani were the most affected microorganisms. Antioxidant activities were evaluated by DPPH and FRAP methods; the extract showed a higher reducing capability than anti-radical activity. Moreover, we found that in different cancer cell models the anthocyanins cause inhibition of proliferation and apoptosis in a dose dependent manner. These biological activities are likely due to the high content of malvidin 3-O-p-coumaroyl-rutinoside-5-O-glucoside and petunidin 3-O-p-coumaroyl-rutinoside-5-O-glucoside.