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Chemical composition and antioxidant activity of essential oil from daucus reboudii coss., an endemic plant of Algeria
No full textChemical composition of the essential oil of Brachyapium dichotomum (L.) Maire
Full text linkThe essential oil obtained by hydrodistillation from the aerial parts of Brachyapium dichotomum (L.) Maire
(Apiaceae), was analyzed by GC-MS for the first time. Sixty-two compounds were detected, accounting for 96.1% of
the total oil, which is characterized by a high content of hydrocarbons derivatives of mono- and sesquiterpenes
(80.3%). The main constituents were α-pinene (36.5%), germacrene D (17.9%), dill apiole (6.7%) and myristicin
(3.5%)
Essential oil content of the flowers of Pituranthos scoparius in Algeria
No full textThe essential oils obtained by hydrodistillation of the flowers of the Algerian Pituranthos scoparius (Coss. & Dur.)Benth.et Hook. (Apiaceae), an endemic species of North Africa, were analyzed by GC-MS. Thirty-one compounds were identified accounting for 99.3 % of the whole essential oil, mainly represented by monoterpenes, followed by phenylpropanoid derivatives. The main constituents of the essential oil were myristicin (24.1%), α-pinene (17.4%), α-phellandrene (15.6%) and sabinene (7.5%
A myristicin-rich essential oil from Daucus sahariensis growing in Algeria
No full textThe essential oils obtained by hydrodistillation from leaves and fruits of Daucus sahariensis Murb. were analyzed by GC/MS. The main constituents of the essential oil from the leaves were myristicin (34.3%), α-pinene (5.4%), cis-chrysanthenyl acetate (5.3%) and epi-!-bisabolol (4.8%), and those from the fruits myristicin (43.9%), α-pinene (13.1%), limonene (9.4%), and cis-chrysanthenyl acetate (7.4%). Myristicin, the main constituent of both essential oils, is generally absent in the oils from other Daucus species, permitting the hypothesis that this compound is a chemical marker of this Saharan specie
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Chemical constituents and anticholinesterase activity of the essential oil of Algerian Elaeoselinum thapsioides (desf.) maire
No full textElaeoselinum thapsioides is an Algerian medicinal plant used in traditional medicine to treat different diseases. The essential oil obtained by hydrodistillation from the aerial parts of Elaeoselinum thapsioides (Desf.) Maire (Apiaceae) growing wild in Algeria, was analyzed by GC-MS for the first time. Forty-five compounds were detected, accounting for 93.8% of the total oil, which was characterized by a high content of hydrocarbons derivatives of monoterpenes (75.9%). Myrcene (61.0%) was the principal constituent of the essential oil, followed by germacrene D (10.3%), α-pinene (6.5%) and β-pinene (2.9%). In vitro anticholinesterase activity of the essential oil was investigated by the Ellman method that evidenced a low acetylcholinesterase and butyrylcholinesterase inhibitory effect
Effect of growth stage on yield and essential oil composition of Daucus sahariensis
No full textThe essential oils obtained by hydrodistillation from Daucus sahariensis Murb. harvested at three different growth stages were characterized by GC/MS analysis. In total, 88 compounds were identified, with myristicin (29.8–51.7%), myrcene (6.7–31.1%), a-pinene (11.6–14.8%), and limonene (5.3 – 11.5%) as main constituents. Monoterpene hydrocarbons were the most represented compounds in the oils of the plant samples collected during the flower-budding and full-flowering periods. On the contrary, during the fruiting stage, the oils were dominated by phenylpropanoids. The essential oils were subject of considerable variation in their composition during the various developmental stages, particularly concerning the content of myrcene that decreased significantly passing from the vegetative to the fruiting stage. Conversely, for myristicin, the opposite trend was observed. Furthermore, the essential-oil yields were quite low during the flower-budding phase (0.27%), but rapidly increased during plant development (0.63 and 0.68% for the flowering and fruiting phases, resp.
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