Wild Thymbra Capitata from Western Rif (Morocco): Essential Oil Composition, Chemical Homogeneity and Yield Variability

Abstract

Essential oils (EO, 15 collective samples and 47 individual samples) of Thymbra capitata collected from Moroccan Western Rif were analyzed using gas chromatography (GC) in combination with retention indices (RI), gas chromatography-mass spectrometry (GC-SM) and 13 C NMR spectroscopy. Twenty components were identified. Carvacrol (68.2%-85.9 %) was by far the major component of all the samples, while the content of thymol (0.1-0.3%) was very low. Other components present in appreciable amounts were γ-terpinene (up to 8.9%), p-cymene (up to 7.1%), linalool (up to 4.4%) and (E)-β-caryophyllene (up to 4.1%). In contrast, the yield of EO varied drastically from sample to sample (0.5-3.7%). No correlation could be established between yield of EO and altitude, pH, chemical composition and granularity of the soil. Cultivation under controlled conditions is suggested to improve the quantitative characteristics of carvacrol-rich Moroccan T. capitata.

Chemical Polymorphism of Origanum compactum Grown in All Natural Habitats in Morocco

“…These findings agree with Bakhy et al . for O. compactum , but they differ with Vokou et al . and Kokkini and Vokou who emphasized that altitude is the most important environmental factor influencing the oil content of O. vulgare subsp .…”

“…Mixed types, combining both thymol and carvacrol, and types containing a high level of precursors, γ ‐terpinene and p ‐cymene, have also been reported . The various compositions have been summarized in a previous paper that described also the chemical variability observed on 36 oil samples isolated from plants harvested in three Moroccan provinces: Chefchaouen, Larache, and Tetouan . Two‐thirds of the samples exhibited carvacrol as major component.…”

“…O. compactum Benth . is the most widespread species in Morocco, extending from the Middle Atlas region delimited by Beni mellal, Azrou, Khenifra, and Oulmès up to the occidental and central Rif region, including the provinces of Tangier‐Tetouan, Chefchaouen, Taounate, and Ouazzane . O. compactum Benth ., known locally as ‘Zaâtar’, constitutes one of the most appreciated aromatic herbs, widely used in Moroccan folk medicine in the form of infusions and decoctions to threat broncopulmonary, gastric acidity, gastrointestinal diseases, and numerous infections .…”

Antimicrobial Activity of Ammodaucus leucotrichus Fruit Oil from Algerian Sahara

“…Identification of the components by GC(RI), GC-MS and 13 C NMR was performed as previously reported [10]. In the investigated samples individual components were identified by NMR at contents as low as 0.3-0.4%.…”

Chemical Composition of the Fruit Oils of Five Fortunella Species Grown in the Same Pedoclimatic Conditions in Corsica (France)

“…Identification of the components by GC(RI), GC-MS and 13 C NMR was performed as previously reported [30].…”