Chemical Profile, Antioxidant Capacity, and Antimicrobial Activity of Essential Oils Extracted from Three Different Varieties (Moldoveanca 4, Vis Magic 10, and Alba 7) of .

Chemical composition, antioxidant capacity, and antimicrobial activity of lavender essential oils (LEOs) extracted from three different varieties of Mill. (1-Moldoveanca 4, 2-Vis magic 10, and 3-Alba 7) have been determined. These plants previously patented in the Republic of Moldova were cultivated in an organic agriculture system in the northeastern part of Romania and then harvested in 3 consecutive years (2017-2019) to obtain the essential oils. From the inflorescences in the complete flowering stage, the LEOs were extracted by hydrodistillation. Then, their composition was analyzed by gas chromatography coupled with mass spectrometry (GC-MS) and by Fourier Transformed Infrared spectroscopy (FT-IR). The major identified constituents are as follows: linalool (1: 32.19-46.83%; 2: 29.93-30.97%; 3: 31.97-33.77%), linalyl acetate (1: 17.70-35.18%; 2: 27.55-37.13%; 3: 28.03-35.32%), and terpinen-4-ol (1: 3.63-7.70%; 2: 3.06-7.16%; 3: 3.10-6.53%). The antioxidant capacity as determined by ABTS and DPPH assays indicates inhibition, with the highest activity obtained for LEO Alba 7 from 2019. The in vitro antimicrobial activities of the LEOs and combinations were investigated as well, by using the disk diffusion method and minimum inhibitory concentration (MIC) against the Gram-positive bacterial strain (ATCC 6538), Gram-negative (ATCC 27858), (ATCC 25922), the yeast (ATCC 10231), and clinical isolates. Our results have shown that LEOs obtained from the three studied varieties of manifest significant bactericidal effects against tested microorganisms ( and ), and antifungal effects against . The mixture of LEOs ( Alba 7) and geranium, respectively, in tea tree EOs, in different ratios, showed a significant enhancement of the antibacterial effect against all the studied strains, except .