Chemical characterization of cultivated Thymus satureioides Coss. in Morocco for the identification and conservation of elite chemotypes

Endemic to Morocco, Thymus satureioides Coss. is an aromatic and medicinal plant prized for its therapeutic properties, whose conservation and selection are essential in view of its ecological and economic value. Forty cultivated accessions were subjected to hydrodistillation, and 38 chemical compounds were identified from the essential oils obtained using gas chromatography coupled with mass spectrometry (GC-MS) analysis. An average of 59.87% was recorded, with minimum and maximum averages of 48.96% and 67.03%, respectively. Borneol and thymol are the major compounds, with averages of 18.52% and 18.36%, respectively. the coefficient of variation ranged from 6.97% to 147.47%, and the essential oil content showed great variability between accessions, ranging from 64.77% to 54.70% in Errich and Asni, respectively. IJTam recorded the highest average thymol content at 27.50%, while OuS recorded the lowest average at 11%. However, Errich expressed the highest borneol content at 25.22%, followed by OuS2 with an average of 24.16%. The AZAF region recorded the highest average yield of essential oil (4.80%). TAMS had the highest concentration of thymol (27.42%). The highest levels of borneol were recorded in SIFA (23.07%) and RICH (21.95%). The highest concentration of o-Cymene was recorded in AS (11.73%). The PCA expressed 63.88% of the total variability. Axis 1, strongly and negatively correlated with borneol, camphene, carvacrol, and α-pinene, with 46.07%. Axis 2, strongly and negatively correlated with caryophyllene and α-terpinene, expressed only 17.81% of the total variability. A positive correlation was reported between caryophyllene and carvacrol (r = 0.63***) and between myrcene and caryophyllene (r = 0.70***). The Errich region is distinguished by its richness in sesquiterpenes such as α-thujene: 1.74%, β-pinene: 2.06%, limonene: 1.59%, camphor: 0.10%, borneol: 21.96%, terpinen-4-ol: 2.70%, and carvacrol: 5.67%. These compounds give the essential oil significant antimicrobial and antioxidant properties.