Yields and chemical composition of essential oils from Lavandula dentata , Salvia officinalis , and Artemisia herba-alba , effect of Azilal provenance

This study examines the valorization of three aromatic and medicinal plant species cultivated in rural nurseries in the Moroccan High Atlas (Azilal province). It aims to assess the influence of plant origin on essential oil yield and chemical composition for economic valorization. Physicochemical analyses included moisture content determination, essential oil extraction by hydrodistillation, and volatile compound identification using GC-MS. The results showed high moisture levels (65-67%), typical of young plant material, and significant yields, especially for Lavandula dentata (3.2%) and Salvia officinalis (1.97%). Each species presented a distinct chemotype influenced by ecological factors such as altitude, soil type, and sun exposure. Technical constraints related to nursery practices and artisanal extraction methods affected oil quality and stability. Improving local valorization requires better drying techniques, more efficient extraction processes, cooperative training, and a sustainable production chain adapted to local conditions.