Chemical Profiling and Biological Properties of Essential Oils of Lavandula stoechas L. Collected from Three Moroccan Sites: In Vitro and In Silico Investigations

The aim of this study was the determination of the chemical compounds of Lavandula stoechas essential oil from Aknol (LSEO(A)), Khenifra (LSEO(K)), and Beni Mellal (LSEO(B)), and the in vitro investigation of their antibacterial, anticandidal, and antioxidant effects, and in silico anti-SARS-CoV-2 activity. The chemical profile of LSEO was determined using GC-MS-MS analysis, the results of which showed a qualitative and quantitative variation in the chemical composition of volatile compounds including L-fenchone, cubebol, camphor, bornyl acetate, and τ-muurolol; indicating that the biosynthesis of essential oils of Lavandula stoechas (LSEO) varied depending on the site of growth. The antioxidant activity was evaluated using the ABTS and FRAP methods, our results showed that this tested oil is endowed with an ABTS inhibitory effect and an important reducing power which varies between 4.82 ± 1.52 and 15.73 ± 3.26 mg EAA/g extract. The results of antibacterial activity of LSEO(A), LSEO(K) and LSEO(B), tested against Gram-positive and Gram-negative bacteria, revealed that B. subtilis (20.66 ± 1.15–25 ± 4.35 mm), P. mirabilis (18.66 ± 1.15–18.66 ± 1.15 mm), and P. aeruginosa (13.33 ± 1.15–19 ± 1.00 mm) are the most susceptible strains to LSEO(A), LSEO(K) and LSEO(B) of which LSEO(B) exhibits bactericidal effect against P. mirabilis. furthermore The LSEO exhibited varying degrees of anticandidal activity with an inhibition zones of 25.33 ± 0.5, 22.66 ± 2.51, and 19 ± 1 mm for LSEO(K), LSEO(B), and LSEO(A), respectively. Additionally, the in silico molecular docking process, performed using Chimera Vina and Surflex-Dock programs, indicated that LSEO could inhibit SARS-CoV-2. These important biological properties of LSEO qualify this plant as an interesting source of natural bioactive compounds with medicinal actions.