Comprehensive Quality Assessment of Dittrichia viscosa (L.) from Southeast Morocco: Physicochemical Properties, Phytochemical Composition, Microbiological Profile and Mineral Content Analysis

Dittrichia viscosa (L.) Greuter, is a perennial herb renowned for its therapeutic properties. The present study aimed to carry out a comprehensive assessment of the quality of D. viscosa aerial parts. The aerial parts of D. viscosa were sourced from the Ouarzazate region in southeast Morocco. Dried powdered D. viscosa aerial parts were extracted using aqueous ethanol, and cyclohexane by various extraction techniques. Essential oil was obtained by hydrodistillation in a Clevenger-type apparatus. The quality of the plant material, including its essential oil was assessed by evaluating various parameters including extraction yields, organoleptic and physicochemical properties, phytochemical composition, mineral content, and microbiological profile. Results showed that the yields of the essential oil and other extracts from D. viscosa aerial parts significantly depends on the extraction solvents and techniques used. The hydroethanol extract produced the highest levels of total phenol and total tannin contents, whereas the cyclohexane extract showed the highest total flavonoid content. The organoleptic analysis indicated a slimy, dark yellow oil, with an herbaceous camphoraceous odour The essential oil was predominantly composed of sesquiterpenes, including γ-Muurolene, α-Muurolene, and β-Cadinene. The quality assessment indices and physicochemical properties suggested a commendable quality of the oil, with properties comparable to or exceeding those of other species within the Asteraceae family. Microbiological analysis showed that D. viscosa conformed to WHO standards for herbal medicines, which suggests that the plant is safe for consumption. However, the mineral analysis showed elevated cadmium level, hence the need for caution in its medicinal use.