A Comparative Study ofMelissa officinalisLeaves and Stems Ethanolic Extracts in terms of Antioxidant, Cytotoxic, and Antiproliferative Potential

Abstract

Melissa officinalisL. has attracted an increased interest in recent years due to its multiple pharmacological effects. This study aimed to compare twoM. officinalisethanolic extracts, obtained from leaves and stems, with regard to their antioxidant activity, total phenolic content, and cytotoxic effects.M. officinalisethanolic extracts showed a very good antioxidant activity in the DPPH test, correlated with the content in total phenols: higher in the case ofM. officinalisfrom leaves extract (32.76 mg GAE/g) and lower forM. officinalisfrom stems extract (8.4 mg GAE/g). The lemon balm extracts exerted a cytotoxic effect on breast cancer cells (MDA-MB-231) even at low concentrations (100 μg/mL), whereas, in the case of healthy HaCat cells,M. officinalisleaves extract only displayed cytotoxicity at much higher concentrations (500 and 1000 μg/mL) andM. officinalisstems extracts were highly cytotoxic (starting at 100 μg/mL). In addition, the extracts exerted inhibitory effects on cell migration and proliferation. These results provide information that confirms the high potential ofM. officinalisas a source of chemopreventive agents. Moreover, these data can be considered a solid background for furtherin vivostudies involving mice bearing breast tumors.