Chemical variability of the berry essential oil of two subspecies of Juniperus oxycedrus L. from Northwestern Algeria.

The chemical composition of 33 oil samples isolated from the berries of individual trees of two subspecies of Juniperus oxycedrus L., collected in four locations in Tlemcen and Aïn Temouchent provinces, was investigated by GC-FID, GC/MS and 13CNMR. In total, 83 compounds were identified, accounting for 85.9% to 98.6% of the total composition. Yields ranged between 0.02 and 0.40% (w/w). All compositions were submitted to statistical analysis. Combination of hierarchical clustering dendrogram and principal component analysis suggested the existence of two groups, the second group being sub-divided into two sub-groups. Groups and sub-groups were distinguished with respect to their contents of α-pinene, germacrene D, myrcene and, to a lesser extent, of manoyl oxide. The chemical composition of the oils belonging to subsp. oxycedrus was largely dominated by monoterpenes. α-Pinene (23.7 - 63.2%) and germacrene D (4.5 - 25.4%) were the major components, followed by myrcene (3.1 - 16.7%). Conversely, samples oils of subsp. macrocarpa were largely dominated by germacrene D (4.4 - 30.0%), followed by a lower content of α-pinene (10.0 - 24.3%) and myrcene (1.0 - 4.3%) and a significant content of manoyl oxide (4.3 - 9.9%).

Chemical Variability and Anti-Inflammatory Activity of Rosmarinus officinalis L. Leaf Essential Oil from Algerian Sahara.

The chemical composition of 71 oil samples from the leaves of Rosmarinus officinalis L., harvested in three provinces: Naâma (Western Algeria), Béchar and Adrar (Algerian Sahara), was investigated by GC-FID, GC/MS and 13CNMR. In total, 52 compounds were identified accounting for 88.8 % to 99.9 % of the total composition. The chemical composition of the oils was largely dominated by monoterpenes, with 1,8-cineole (9.7-70.2 %), camphor (0.3-31.0 %) being the major compounds followed by borneol (0.3-21.0 %), α-pinene (4.5-14.5 %), ß-pinene (0.1-12.0 %), linalool (0.7-9.9 %) and verbenone (up to 11.1 %) which was present only in the samples harvested in Adrar. All compositions (71 samples) were submitted to statistical analysis. Combination of hierarchical clustering dendrogram and principal component analysis suggested the existence of three groups (one of these being subdivided into two sub-groups) which were distinguished on the basis of 1,8-cineole, camphor and verbenone contents. Four essential oil samples, containing 1,8-cineole and/or camphor as main components, exhibited anti-inflammatory activity against lipoxygenase, with IC50 values in the range 93 to 155 µg/mL.

Composition, Chemical Variability and Biological Activity of Cymbopogon schoenanthus Essential Oil from Central Algeria.

Cymbopogon schoenanthus (L.) Spreng. (Poaceae) is an aromatic plant whose aerial parts and rhizome produced an essential oil with pleasant odor. A chemical variability has been observed depending of the countries where the plant grows wild, including Algeria. The chemical compositions of 24 oil samples isolated from plants harvested in Central Algeria have been investigated, to evidence homogeneity or chemical variability within a given area of harvest. Twenty of these were dominated by cis- and trans-p-menth-2-en-1-ols (22.6 %±3.6 and 14.3 %±1.7, resp.) beside four atypical compositions. Otherwise, aerial parts and rhizomes produced similar essential oils. Lastly, a fair antimicrobial activity was measured against Staphylococcus aureus strain, while the antioxidant potential was low.

Biological Activities and Chemical Composition of Santolina africana Jord. et Fourr. Aerial Part Essential Oil from Algeria: Occurrence of Polyacetylene Derivatives.

The chemical composition of 18 oil samples of Santolina africana isolated from aerial parts at full flowering, collected in three locations in eastern Algeria was determined by GC(RI), GC/MS and 13C-NMR analysis. The major components were: germacrene D, myrcene, spathulenol, α-bisabolol, ß-pinene, 1,8-cineole, cis-chrysanthenol, capillene, santolina alcohol, camphor, terpinen-4-ol and lyratol. The chemical composition appeared homogeneous and characterized by the occurrence of four derivatives which exhibited a conjugated alkene dialkyne moiety. They were identified for the first time in an essential oil from S. africana. The collective oil sample exhibited moderate antimicrobial and antioxidant activities whereas the anti-inflammatory activity presented a real potential. IC50 value of Santolina africana essential oil (0.065 ± 0.004 mg/mL) is 5-fold higher than IC50 value of NDGA used as positive control.

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 13 C-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 Composition and Antimicrobial Activity of the Essential Oil from Aerial Parts of Algerian Pulicaria mauritanica.

One oil sample isolated from aerial parts of Pulicaria mauritanica Coss. from Western Algeria has been analyzed by GC(RI), GC-MS and ¹³C NMR. In total, 21 components, accounting for 97.0% of the oil, were identified. Then, 36 oil samples coming from plants harvested at two flowering periods in three locations were analyzed by GC(RI) and ¹³C NMR. Although all the oil samples exhibited similar composition, dominated by carvotanacetone (89.2-96.1%), the yield of essential oil varied drastically from sample to sample (0.35-1.44%), depending on the location of harvest. The essential oil displayed moderate antimicrobial effect against bacteria, yeast and filamentous fungi (MIC = 2-4 µL/mL).

Chemical Variability of the Essential Oil Isolated from Aerial Parts of Tetraclinis articulata from North-Western Algeria.

The objective was to investigate the yield and chemical composition of 50 essential oil samples isolated from leaves and flowers of Tetraclinis articulata harvested in eight locations (coastal township and highlands) of Tlemcen Province (North-Western Algeria). Essential oil yields varied drastically from sample to sample (0.03 to 0.86%, w/w). No direct correlation was observed between the yield and the altitude of the harvest areas. The oils consisted mainly of monoterpenes: α-pinene (9.2-56.5%), bornyl acetate (1.2-45.1%), camphor (0.5-40.3%), borneol (0.2-12.9%), limonene (3.6-12.5%), and myrcene (1.6-9.7%). Sesquiterpenes were represented by germacrene D (up to 14.2%) and (E)-ß-caryophyllene (up to 13.3%). PCA analysis of the data allowed the distinction of two groups within the samples. The composition of group I (9 samples) was dominated by camphor, (Mean = 30.9%) followed by α-pinene (M = 19.1%) and bornyl acetate (M = 11.4%). Group II was divided into two sub-groups. Samples of sub-group IIA (8 samples) contained mainly α-pinene (M = 45.4%). Samples of the largest group IIB (33 samples) were characterized by similar contents of α-pinene (M = 28.2%) and bornyl acetate (M = 24.5%) and the occurrence of camphor to a lesser extent (M = 10.0%).

Potential assessment of Rumex vesicarius L. as a source of natural antioxidants and bioactive compounds.

The present work is designed to evaluate the antioxidant activities of hydroalcoholic extract (HAE) and its fractions (viz., hexane (HF), chloroform (CF), ethyl acetate (AF), n-butanol (BF) and water (WF)) obtained from aerial part of Rumex vesicarius L. by using different in vitro antioxidant assays. The content in pigments (carotenoids and chlorophylls), total phenolics, flavonoids and tannins were determined using spectrophotometric methods. Qualitative analyses of major phenolics by TLC analysis were also evaluated. Experimental results obtained show that R. vesicarius is a rich source of ß-carotene (116.83 ± 1.60 µg/g DW), lycopene (156.40 ± 1.59 µg/g DW) and chlorophyll a (271.45 ± 3.46 µg/g DW). The greatest antioxidant activity was found in AF (IC50.DPPH = 0.07 ± 0.00 mg/ml) followed by BF and CF (0.15 ± 0.00 and 0.16 ± 0.00 mg/ml, respectively). These fractions were also better in their effect on reducing the oxidation of ß-carotene. Reducing power of crude methanol extract/fractions increased with increasing concentration of the extract. The amount of total phenolics varied from 0.37 ± 0.01 to 43.28 ± 0.28 mg GAE/g of dry weight, HAE had the higher content (43.28 ± 0.28 mg GAE/g of DW). A negative correlation was found between phenolic compounds and the antioxidant efficiencies of the crude extract/fractions, suggesting that phenolic compounds are not the only contributors to the antioxidant activities of Rumex vesicarius. The present findings suggest that Rumex vesicarius L. can be used as natural antioxidant source to prevent damage associated with free radicals.

Antimicrobial activity of Ammodaucus leucotrichus fruit oil from Algerian Sahara.

Three fruit oil samples of Ammodaucus leucotrichus Cosson & Durieu from Algerian Sahara were obtained by hydrodistillation and analyzed by GC(RI), GC-MS and 13C NMR spectroscopy. The main compounds were perillaldehyde (87.0-87.9%) and limonene (7.4-8.2%). The antimicrobial effect of the essential oil was evaluated against bacteria, yeasts and filamentous fungi. High antibacterial activity was observed against Escherichia coli, Staphylococcus aureus. Enterobacter cloaceae, Bacillus cereus and Salmonella typhimurium, with MIC values between 0.5-1.0 microL/mL. Fungal strains were also sensitive to the essential oil (MIC values: 0.25-0.75 microL/mL).The most potent activity was observed against the filamentous fungi, Fusarium oxysporum and Aspergillusflavus (0.25-0.50 microL/mL).

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 (13) C-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, ß-phellandrene, and germacrene D contents. In most oil samples, α-pinene (30.2-76.7%) was the major compound, associated with ß-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%).

Isothymol in Ajowan essential oil.

Ajowan is a popular spice that is used in folk medicine in Algeria. Most studies reported that thymol is the main component of the seed oil. Isothymol was reported to be a constituent of essential oil isolated from aerial parts. Using plants harvested in five different locations in north western Algeria, every two weeks during the flowering stage, we demonstrated that isothymol was the major component when the plant was collected near the sea at low altitude and at the beginning of the flowering stage. In other cases, thymol is the predominant constituent.