Abstract
In this contribution, we investigate the impact of different extraction methods on the chemical profile of stems and leaves of Melissa officinalis L. Extemporaneous preparations (infusions) were performed and revealed a significant disparity in the chemical profiles of the leaves and stems, with key constituents like rosmarinic acid being notably absent in stem infusions. Subsequent analyses employing sequential maceration with ultrasound and solvents such as hexane, ethyl acetate, and ethanol, however, demonstrated an equivalency of chemical profiles across both plant parts, including the presence of rosmarinic acid. These findings underscore the critical role of extraction methodology in determining the chemical profile of plant-based medicinal preparations.