Chemical Variability of the Essential Oil of Pituranthos scoparius from Algeria

The chemical composition of 93 oil samples from the aerial parts of Pituranthos scoparius, harvested in three regions of Algeria, was investigated by GC‐FID, GC/MS and ¹³C‐NMR. Monoterpene hydrocarbons dominated in association with phenylpropanoids and a chemical variability was found highlighting three clusters. The composition of group I (36 samples) exhibited an atypical composition characterized by a very high contents of 6‐methoxyelemicine (13.0 – 59.6%), followed by sabinene (1.1 – 43.0%) and limonene (6.6 – 39.0%), while the samples of group II (12 samples) contained a high content of limonene (9.2 – 44.0%), followed by myristicine (0.0 – 29.4%) and a lower amount of sabinene (0.8 – 2.3%). Group III (45 samples) could be divided in two subgroups. Subgroup SGIIIA was characterized by a very high content of sabinene (28.0 – 55.6%), followed by elemicine (0.0 – 29.1%), while the samples belonging to SGIIIB were characterized by the lower content of sabinene (6.2 – 35.5%) and a significant content of myristicine (1.5 – 32.4%), α‐pinene (4.2 – 31.0%) and dill apiole (0.1 – 31.4%). Each harvested region was characterized by a different chemical composition.     

Chemical Variability of the Essential Oil of Juniperus phoenicea var. turbinata from Algeria

The chemical composition of 50 samples of leaf oil isolated from Algerian Juniperus phoenicea var. turbinata L. harvested in eight locations (littoral zone and highlands) was investigated by GC‐FID (in combination with retention indices), GC/MS, and ¹³C‐NMR analyses. The composition of the J. phoenicea var. turbinata leaf oils was dominated by monoterpenes. Hierarchical cluster and principal component analyses confirmed the chemical variability of the leaf oil of this species. Indeed, three clusters were distinguished on the basis of the α‐pinene, α‐terpinyl acetate, β‐phellandrene, and germacrene D contents. In most oil samples, α‐pinene (30.2–76.7%) was the major compound, associated with β‐phellandrene (up to 22.5%) and α‐terpinyl acetate (up to 13.4%). However, five out of the 50 samples exhibited an atypical composition characterized by the predominance of germacrene D (16.7–22.7%), α‐pinene (15.8–20.4%), and α‐terpinyl acetate (6.1–22.6%).     

Distribution of phenolic compounds within seed and seedlings of two Vicia faba cvs differing in their seed tannin content,and study of their seed and root phenolic exudations

The present study analysed the physiology of phenolic exudation by the seed and the root of two Vicia faba cultivars, one rich in condensed tannin (cv. Alfred) and one free-tannin cultivar (cv. Blandine). We first analysed the phenolic exudation from the intact seeds and from the different seed tissues (coat and cotyledon separately). Results indicated that the whole seed exudation in water after 24 h was reduced when the seed was incubated at 4°C in comparison with 30°C. The characterisation and separation of phenolic compounds was achieved by HPLC procedures. The two cultivars of Vicia faba, cv. Blandine and cv. Alfred, were containing in the seed two different chemical patterns. The phenolic patterns of the cv. Alfred seed coat was dominated by catechin derivatives, condensed tannins and flavones. The phenolic pattern of cotyledon and whole seed are very closed and namely made of phenolic acids, and catechin, and flavones as minor compounds. For cv. Blandine, the seed coats contain phenolic acids, flavones, flavonols and dihydroflavonols; the phenolic profile of whole seeds and cotyledons were mainly based on phenolic acids. The kinetic of root phenolic exudation was analysed on the first 21 days of the root growth; the data indicated that phenolic compounds were rapidly released from the emerging root as the amounts of phenolic compounds in exudates were maximum the first day after the seed germination.The HPLC analysis of the phenolic compounds exudated by the root, depicted catechin, phenol acids derivatives and various flavones and flavanones.