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Biological activity of ethanol extract from leaves of Rosmarinus eriocalyx
Full text linkAging or senescence is a complex and inevitable process, which is not only attributed to individual genetic variation but also to external factors such as environmental conditions, nutrition, alcohol, and diseases [1]. The most widely accepted theory, that have been proposed to explain aging, is the free radical theory [2]. Aging and related diseases result from accumulated oxidative damage to cell constituents and tissues caused by excessive exposure to free radicals. Antioxidants, which mediate the imbalance between intracellular antioxidant defenses and oxidative damage by reducing the reactive oxygen species (ROS) levels, are believe to be able to reduce stress-induced premature senescence or slow down replicative senescence [3].
Rosmarinus eriocalyx (Jord. & Fourr.) is an aromatic evergreen bush belonging to Lamiaceae family and endemic to Algeria, Morocco and Spain, where it is used as a condiment to flavor soup and meat and as a traditional remedy [4]. The plant volatile fraction is characterized by the monoterpene ketone camphor, whereas its ethanolic extracts are rich sources of phenolic acids and diterpenes such as rosmarinic acid, carnosic acid and carnosol that are the main responsible for the noteworthy antioxidant activity [5].
In this setting, we aimed to evaluate R. eriocalyx biological activity in order to propose the plant as an anti-aging agent. For this purpose, we determined the cytotoxic activity of polar extracts obtained from leaves, flowers, and stems of R. eriocalyx on human fibroblast and human tumor cell lines (A375, MDA-MB 231, and T98G) by MTT assay [6]. Results showed that the ethanolic extract of leaves resulted the most active against A375 human melanoma cell line (IC50 value of 17.8 μg/ml). The total phenolic content values reported for R. eriocalyx ethanolic and aqueous extracts showed slight differences and free radical scavenging activity was stronger for ethanolic extracts than aqueous ones. On this basis, we selected the R. eriocalyx ethanolic extract to determine the antioxidant activity on human fibroblast by measuring its ability to prevent oxidation in cells using a ROS fluorescent probe (DCFH-DA) [7]. Results showed a remarkable activity in preventing oxidation of cells induced by 2.2’-azobis -2-amidinopropane (ABAP). Afterwards, we tested the same extract on the H2O2-induced premature senescence in young fibroblast cells where -galactosidase (SA--gal) activity was used to measure cell senescence [8]. Preliminary data showed a reduction of H2O2 stress-induced premature senescence indicating the potential of R. eriocalyx leaf extract to be formulated as an anti-aging agent.
References
[1] N. Getoff. Anti-aging and aging factors in life. The role of free radicals. Radiat. Phys. Chem. 2007, 76,1577-1586.
[2] D. Harman. Aging: a theory based on free radical and radiation chemistry. J. Gerontol. 1956, 11, 298-300.
[3] D. Fusco, G. Colloca, M.R. Lo Monaco, M. Cesari. Effects of antioxidant supplementation on the aging process. Clin. Interv. Aging. 2007, 2, 377-387.
[4] M.S. Bendeddouche, H. Benhassaini, Z. Hazem, A. Romane. Essential oil analysis and antibacterial activity of Rosmarinus tournefortii from Algeria. Nat. Prod. Commun. 2011, 6, 1511-1514.
[5] H. Bendif, M. Boudjeniba, M. Djamel Miara, L. Biqiku, M. Bramucci, G. Caprioli, G. Lupidi, L. Quassinti, G. Sagratini, L.A. Vitali, S. Vittori, F. Maggi. Rosmarinus eriocalyx: An alternative to Rosmarinus officinalis as a source of antioxidant compounds. Food Chem. 2017, 218, 78-88.
[6] L. Quassinti, G. Lupidi, F. Maggi, F. Papa, S. Vittori, A. Bianco, M. Bramucci . Antioxidant and antiproliferative activity of Hypericum hircinum L. subsp. majus (Aiton) N. Robson essential oil. Nat. Prod. Res. 2013, 27, 862-868.
[7] K.L. Wolfe, R.H. Liu. Cellular antioxidant activity (CAA) assay for assessing antioxidants, foods, and dietary supplements. J. Agric. Food Chem. 2007, 55, 8896-8907.
[8] D.J. Kurz, S. Decary, Y. Hong, J.D. Erusalimsky. Senescence-associated -galactosidase reflects an increase in lysosomal mass during replicative ageing of human endothelial cells. J. Cell Sci. 2000, 113, 3613–3622
Chemical composition and antibacterial activity of essential oils from Daucus sahariensis Murb. roots and stems
No full textDaucus genus (Apiaceae) comprises economically relevant plants distributed in temperate regions. These plants are used mainly as food but are also known for their biological properties. Here, the essential oils (EOs) obtained by hydro-distillation of roots and stems of D.sahariensis Murb. growing in Algerian Sahara were studied by GC-MS analysis. Fifty-two and fifty-five compounds were identified from the roots and stems, representing 95.1% and 93.8% of the whole EOs respectively. The main constituents of the EO from roots were myristicin (29.2%), (E)-anethole (14.2%), cis-chrysanthenyl acetate (8%) and estragol (7.5%). In the EO from stems, the main constituents were α-pinene (18.6%), myrcene (16.7%), limonene (13.7%) and myristicin (8%). The antibacterial activity of EOs was evaluated by disc diffusion method and tested against Gram-positive and Gram-negative bacteria. Results showed a mild activity against Bacillus subtilis and Klebsiella pneumoniae for both EOs, which can be potentially used as antibacterial in phytotherapy
Total phytochemical analysis of Thymus munbyanus subsp. coloratus from Algeria by HS-SPME-GC-MS, NMR and HPLC-MSn studies
Full text linkIn this article, we report a comprehensive characterization of volatile and polar constituents extracted from the aerial parts of Thymus munbyanus subsp. coloratus, a shrub that is used as culinary ingredient and as traditional medicine in Algeria, mainly to treat respiratory and gastrointestinal disorders and endocrine dysfunctions. Headspace solid phase microextraction (HS-SPME) coupled with gas chromatography-mass spectrometry (GC-MS) was used to assess volatile constituents, whereas the phytochemical composition of solid residues obtained from extraction with solvents at diffrent polarity was obtained by an integrated Nuclear Magnetic Resonance (NMR) and liquid chromatography coupled with tandem mass spectrometry (LC-MSn) approach. Fourty-five apolar ccompounds were identified, mainly oxygenated monoterpenes (65.8%), sesquiterpene hydrocarbons and nonoterpene hydrocarbons (18.6 and 14.5%, respectively). On the other hand, LC-MSn and NMR analyses revealed the presence of aglyconic and glycosilated flavonoids, phenylpropanoid derivatives and triterpenoid acids related to oleanolic acid, mainly in the methanol, dichloromethane and hexane extracts. Overall, these data indicate that Thymus munbyanus subsp. coloratus could be a potential source of antioxidants and bioactive compounds, and our results represent a starting point for further research on this plant species
Chemical Composition and Antioxidant Activity of Essential Oil from Daucus reboudii Coss., an Endemic Plant of Algeria
Full text linkPlants of the Daucus genus (Apiaceae) are used worldwide as traditional medicines or culinary ingredients. In this work, in order to explore a new chemotype, the essential oil obtained from the aerial parts of Daucus reboudii Coss., collected from the National Park of Gouraya (Bejaïa, Algeria), was analyzed by GC-MS. Twenty-eight compounds were identified, accounting for 96.6% of the total oil. (E)-anethol was the main constituent (59.4%), followed by estragol (21.2%) and dodecanal (4.4%). (E)-anethol is an uncommon constituent of Daucus genus, hence it could be considered as a marker that contributes to differentiating D. reboudii from other species. Metal chelating, ABTS•+ and DPPH• assays were performed to determine the antioxidant activity. The highest activity was revealed by the DPPH• method, where D. reboudii essential oil showed a significantly higher activity compared to the reference standard BHT at doses of 50 and 100 μg/mL. Results suggest that the essential oil from D. reboudii could have a potential use in the food industry as food preservative. Nevertheless, further studies are needed to assess its applicability, and to elucidate also the composition of non-volatile compounds of this plant
NMR, HS-SPME-GC-MS and HPLC-MS(n) analyses of phytoconstituents and aroma profile of Rosmarinus eriocalyx L
No full textIn this work a comprehensive study on the chemical constituents of the aerial parts of Rosmarinus eriocalyx L. (Lamiaceae), an aromatic shrub traditionally consumed as a food and herbal remedy in Algeria, is presented. The aroma profile was analysed by headspace solid phase microextraction (HS-SPME) coupled with gas chromatography-mass spectrometry (GC-MS), whereas the crude extract constituents were analyzed by (1) H-NMR and by high-performance liquid chromatography coupled with mass spectrometry (HPLC-MS(n) ). Thirty-nine volatile compounds, most of them being monoterpenes, have been identified, with camphor, camphene and α-pinene as the most abundant constituents. (1) H-NMR analysis revealed the presence of phenolic and betulinic acid while HPLC-MS(n) allowed the identification of glycosilated and aglyconic flavonoids as well as phenylpropanoid derivatives. Some of these constituents, namely as betulinic acid, rosmanol and cirsimaritin were reported for the first time in R. eriocalyx. This article is protected by copyright. All rights reserved
Chemical composition and insecticidal activity of Artemisia absinthium L. essential oil against adults of Tenebrio molitor L.
No full textMany researchers and manufacturers around the world have shown interest in essential oils and their components.
Artemisia absinthium L., commonly known as wormwood, is a medicinal and aromatic bitter herb
frequently used in traditional medicine since ancient times. The objective of this research was to study the
chemical composition and evaluate the insecticidal activities of A. absinthium essential oil (AEO) against Tenebrio
molitor L., mealworm battle. We explored its effectiveness through several means, including direct contact,
fumigation and repulsion of insects. Phytochemical analysis was performed using GC-MS technique. The main
components identified in the essential oil were camphor (32.34%), chamazulene (13.92%), and terpinen-4-ol
(10.18%). These results highlight that Algerian A. absinthium plants are valuable resources due to their bioactive
compounds. In particular, the results obtained in our investigation suggest that the essential oil obtained
from A. absinthium has the potential to be used as a natural bioinsecticide
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
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
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