HPLC fingerprint of a flower extract of Tilia × viridis and correlation with antiproliferative and antioxidant activity.

Tilia species have been used in Europe and in America to treat anxiety and also for the treatment of colds, influenza, bronchitis, fever and inflammation. Tilia × viridis is a Tilia species distributed widely in Buenos Aires, Argentina. The flavonoids present in Tilia species have antioxidant properties, acting as reactive oxygen species (ROS) scavengers, principally on hydrogen peroxide (H(2)O(2)) and the superoxide anion (O(2)(·-)), which are involved in many diseases, including cancer. The aim of this study was to determine the phytochemical pattern of the ethanol extract of Tilia × viridis, principally the flavonoid content, and to evaluate the antiproliferative effects on both normal and tumoral cells, and the antioxidant activity in relation to H(2)O(2) modulation. The extract was found to present a selective antiproliferative activity on a lymphoma cell line and this was related to free radical scavenging activity. In addition, one of its main compounds, rutin, showed antioxidant effects related to peroxidase activity. T. × viridis may therefore be a source of antioxidant compounds that contribute to a selective antiproliferative action on tumoral cells, acting by modulation of H(2)O(2) levels.