How gamma and electron-beam irradiations modulate phenolic profile expression in Melissa officinalis L. and Melittis melissophyllum L.

•Gamma and e-beam irradiations were tested as viable conservation technologies.•The effects on phenolic profiles of highly consumed infusions were assessed.•Infusions obtained from irradiated plants presented higher phenolic contents.•Phenolic compounds' differences were dependent on irradiation type and dose.

Owing to the overall increase in herbal infusions' consumption, there's a progressively higher need of suitable plant material, as well as adequate conservation techniques to maintain its quality. Among, the available technologies, irradiation is gaining interest as a feasible preservation method. In line with this approach, this wok was designed to evaluate the effects of electron-beam and gamma irradiation over the phenolic profiles of two plant species Melissa officinalis L. (LB) and Melittis melissophyllum L. (BB). Individual phenolics were characterized by high-performance liquid chromatography coupled to a diode array detector and a mass spectrometer (HPLC-DAD-ESI/MS). Irradiated samples showed a general increase in individual phenolic contents, especially in lithospermic acid A in LB and 5-O-caffeoylquinic acid in BB. Thus, this study revealed the potential usefulness of both conservation technologies when employed to this type of plants.