Agastache Species (Lamiaceae) as a Valuable Source of Volatile Compounds: GC–MS Profiling and Investigation of In Vitro Antibacterial and Cytotoxic Activities

Nowadays, there is an increasing interest in the study of medicinal and aromatic plants, due to their therapeutic properties that correlate with the presence of different active compounds. Agastache species (sp.) are aromatic plants that belong to the Lamiaceae family, originating from North America and East Asia. The present study aimed to evaluate the composition of essential oils (EOs) obtained from different Romanian cultivated Agastache sp. and to investigate their antibacterial and cytotoxic activities. The gas chromatography-mass spectrometry (GC–MS) screening revealed that menthone was the dominant constituent of A. foeniculum (31.58%), A. rugosa (39.60%) and A. rugosa ‘After Eight’ (39.76%) EOs, while estragole was the major constituent of A. foeniculum “Aromat de Buzău” (63.27%) and A. mexicana (41.66%) EOs. The investigation of the antiproliferative effect showed that A. rugosa and A. foeniculum “Aromat de Buzău” EOs had significant cytotoxic activity on MDA-MB-231 and HEPG2 tumour cell lines, with the most promising effect on the MDA-MB-231 breast cancer cell line for A. foeniculum “Aromat de Buzău” EO (IC50 = 203.70 ± 0.24 μg/mL). Regarding the antibacterial activity, A. rugosa EO was most active against E. coli (8.91 ± 3.27 μL/mL) and S. aureus (10.80 ± 0.00 μL/mL). To the best of our knowledge, this is the first report on the cytotoxic effect of Agastache sp. EOs on MDA-MB-231, HCT116 and HEPG2 tumour cell lines. The results of our study provide new and promising information for the subsequent in vivo study of the pharmacological properties of Agastache sp. essential oils.