To ensure the preservation and sustainable use of Lavandula dentata, we have examined the impact of different growth conditions on cultivated and wild L. dentata essential oils (EOs) composition and biological activities, along with the biomass of root and soil microorganisms. Gas chromatography analysis revealed 21 and 23 components in the EO of the wild and culti-vated plants, accounting for over 98% of the total composition in both cases. The major com-pounds of wild EO were borneol (49.47%), eucalyptol (23.01%), β-pinene (3.95%), β-eudesmol (3.79%), and myrtenol (3.61%). In contrast, the EO extracted from cultivated plants was charac-terized by a high content of borneol (32.83%), isobornyl acetate (24.45%), eucalyptol (14.71%), and α-pinene (5.83%). Unique compounds were found in wild and cultivated EO, such as lin-alool, cis-verbenol, carveol, α-selinene, and terpinyl acetate or tricyclene, d-limonene, cam-phene hydrate, and isobornyl acetate, respectively. PLFA analysis revealed a higher microbial biomass in both soil (10.393 µg/g) and the roots (68.04 µg/g) of the wild plants compared to the cultivated ones (3.91 µg/g in soil and 62.04 µg/g in roots), driven especially by gram negative bacteria in soil, and by saprotrophic fungi in the roots. The biological activities of the EOs var-ied with, the growth conditions, with the wild EO demonstrating superior antibacterial, anti-fungal, antioxidant, and nematicidal properties. Our results highlight the importance of natu-ral growth conditions in shaping the chemical composition of L. dentata EO. Nevertheless, cul-tivation practices could serve as a promising alternative to ensure the sustainable use of this species, provided they are managed under appropriate agronomic and ecological conditions

To ensure the preservation and sustainable use of Lavandula dentata L., we examined the impact of various growth conditions on the composition of essential oils extracted from the leaves of both cultivated and wild L. dentata. Additionally, we assessed the biological activities of these essential oils, along with the biomass of the root and soil microorganisms. Gas chromatography analysis revealed 21 and 23 components in the EO of the wild and cultivated plants, accounting for over 98% of the total composition in both cases. The major compounds of wild EO were borneol (49.47%), eucalyptol (23.01%), β-pinene (3.95%), β-eudesmol (3.79%), and myrtenol (3.61%). In contrast, the EO extracted from cultivated plants was characterized by a high content of borneol (32.83%), isobornyl acetate (24.45%), eucalyptol (14.71%), and α-pinene (5.83%). Unique compounds were found in wild and cultivated EO, such as linalool, cis-verbenol, carveol, α-selinene, and terpinyl acetate or tricyclene, d-limonene, camphene hydrate, and isobornyl acetate, respectively. PLFA analysis revealed a higher microbial biomass in both soil (10.393 µg/g) and the roots (68.04 µg/g) of the wild plants compared to the cultivated ones (3.91 µg/g in soil and 62.04 µg/g in roots), driven especially by Gram-negative bacteria in soil, and by saprotrophic fungi in the roots. The biological activities of the essential oils showed some variations with growth conditions, with the wild EO generally exhibiting slightly higher antibacterial, antifungal, antioxidant, and nematicidal activities in certain assays. Overall, our findings indicate that the essential oils from wild and cultivated L. dentata exhibit comparable biological value, although some differences were observed. In particular, the wild EO tended to show significantly higher biological activities in certain assays, which may be associated with its distinct chemical composition and growth environment. However, these differences were moderate and not consistently significant across all tests. Therefore, properly managed cultivation can be a dependable alternative for producing L. dentata essential oil, helping to reduce pressure on natural populations.

Thymus satureioides Coss. is an endemic Moroccan medicinal and aromatic species of high socio-economic value, is increasingly threatened by overexploitation and continued reliance on wild harvesting. Sustainable cultivation could reduce pressure on natural populations, yet its effects on essential oil (EO) composition, bioactivity, and associated microbial diversity remain poorly understood. This study compared EO yield, chemical composition, antioxidant, antimicrobial, and nematicidal activities, and soil microbial diversity (PLFA) between wild (WT) and cultivated (CT) populations. Gas chromatography–MS analysis identified 18 and 24 compounds in WT-EO and CT-EO, respectively. Thymol and endo-borneol were the major constituents in both oils, with thymol occurring at higher levels in CT-EO (31.83%) than WT-EO (24.79%), while endo-borneol accounted for 15.61% and 16.37%, respectively. WT-EO was further characterized by the exclusive presence of camphor (0.28%). Despite the higher EO yield in CT plants, WT-EO exhibited stronger biological activities. WT-EO showed significantly higher antioxidant capacity, with lower IC₅₀ values than CT-EO in TAC (0.01 vs. 0.02 mg mL⁻¹), DPPH (0.30 vs. 0.60 mg mL⁻¹), and ABTS (0.03 vs. 0.37 mg mL⁻¹) assays. WT-EO also showed stronger antimicrobial activity, with lower MIC values against E. coli (2.5 vs. 3.8 mg mL⁻¹), Pseudomonas aeruginosa (2.5 vs. 3.8 mg mL⁻¹), and Staphylococcus aureus (0.04 vs. 0.50 mg mL⁻¹). At the lowest tested concentration (5 µL mL⁻¹), WT-EO induced significantly higher nematicidal activity than CT-EO, although both oils reached nearly complete juvenile mortality and egg-hatching inhibition at higher concentrations. WT soils also supported greater microbial biomass and a distinct PLFA-based microbial profile than CT soils (9.53 vs. 3.77 µg g⁻¹ soil). These findings support cultivation as a sustainable production strategy while highlighting the importance of conserving WT populations as reservoirs of chemical and microbial diversity.