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Riahi L.,Center de Biotechnologie de la Technopole de Borj-Cedria | Riahi L.,Manouba University | Ghazghazi H.,Institute Sylvo Pastoral Of Tabarka | Ayari B.,University of Carthage | And 5 more authors.
Industrial Crops and Products | Year: 2015

Variation on yields, chemical composition and biological activities of essential oils of Artemisia absinthium L. collected from four different bioclimatic areas ranging from Humid to Arid stage of Tunisia was investigated. The observed yields of essential oils increase significantly from arid to humid climate. A significant qualitative and quantitative variation of the chemical composition according to the studied localities was revealed. Plants collected from the Inferior Arid bioclimatic region (Gafsa) presented chamazulene, α-thujone and camphor as the main components of their essential oils. However, for Superior Arid (Kasserine) and Semi Arid (El Kef) bioclimatic regions, camphor and chamazulene are the dominant constituents followed by linalool for Kasserine and bornyl acetate for El Kef originated oils. The Humid bioclimatic zone (Ghar Dimaou) showed different chemotype and presented camphor, (Z)-sabinene hydrate and 1-terpinen-4-ol as the major compounds. Based on the two DPPH and ABTS tests, the investigated oils highlighted important in vitro antioxidant capacities which increase significantly from the humid (Ghar Dimaou) to the Inferior Arid bioclimatic zone (Gasfa). Even the investigated essential oils displayed an antimicrobial activity against all the tested bacterial and fungal strains with variable degrees, our findings did not reveal a clear correlation between the antimicrobial properties and the studied bioclimatic zones. © 2014 Elsevier B.V.


Riahi L.,Center de Biotechnologie de la Technopole de Borj-Cedria | Elferchichi M.,University of Carthage | Ghazghazi H.,Institute Sylvo Pastoral Of Tabarka | Jebali J.,Institute Pasteur Of Tunis | And 6 more authors.
Industrial Crops and Products | Year: 2013

The present study is the first investigation of the chemical composition, antioxidant and antimicrobial activities of Mentha rotundifolia L. essential oils in Tunisia. Results show that essential oils from Beja locality were most complex and present 45 compounds representing 96.83% of the total oil composition. The major components of the studied oils in this site are β-Caryophyllene (26.67%), Germacrene D (12.31%) and Carveol (7.38%). 40 components representing 95.81% of the total oil were identified in Bizerte site. Those essential oils are dominated by Pulegone (32.09%), Piperitenone oxide (17.28%) and 5-Acetyl Thiazole (11.26%). Considerable levels of antioxidant activities of the investigated essential oils were highlighted. Variations in antioxidant activities may be attributed to the concentrations of major components and the presence of some phenolic compounds like Diosphenol and 2-Allyl-4-methylphenol. Our results showed strong activities of the investigated oils against all tested microorganisms. The highest antimicrobial activities were observed against Gram+ bacteria followed by Gram- ones then fungal species. © 2013 Elsevier B.V.


Chouchaine M.,British Petroleum | Barbouche N.,Institute National Agronomique Of Tunisie | Benachour K.,University of Mentouri Constantine | Abdellaoui A.G.,Ecole Internationale de Tunis Mission | Khemiri A.,Institute Sylvo Pastoral Of Tabarka
Annales de la Societe Entomologique de France | Year: 2014

The study of the respiration of the honeybee, Apis mellifera intermissa, was carried out on four haplotypes from Tunisia: A1, A4, A8 and A9 and under different temperatures: 0°, 10°, 15°, 20°, 25°, 30° and 35°C. Measurements on 1000 isolated bees (250 of each haplotype) showed that the oxygen consumption varied with temperature. The respiration of each haplotype increased gradually from 0°C to a maximum at 15°C. Beyond this temperature, oxygen consumption gradually decreased. For low temperatures (0° to 10°C), breathing also depended on genetic factors, but although oxygen consumption was low it was never zero. This study showed that there is a difference in oxygen consumption between haplotypes A1 and A8 and A9 and A4 haplotypes for low temperatures. The onset of thermogenesis in haplotypes A1 and A8 occurred at 15°C, whereas in haplotypes A4 and A9, it occurred at a lower temperature, which was found to be 10°C. © 2014 Société entomologique de France.


El Aloui M.,Unite dAgrosylvopstoralisme INERGREF | El Aloui M.,University of Carthage | Mguis K.,Unite dAgrosylvopstoralisme INERGREF | Mguis K.,Tunis el Manar University | And 6 more authors.
Acta Botanica Gallica | Year: 2012

Oils isolated from seeds of Ziziphus zizyphus (L.) H. Karst. were investigated by capillary gas chromatography. A comparison of four Tunisian ecotypes (Sfax, Choutrana, Mahres and Mahdia) shows that they differ only in the quantitative composition, while the qualitative profiles are similar. Ten fatty acids are identified from seed oils. The qualitative study shows that oleic acid is the major compound in Sfax and Mahdia ecotypes seed oils. The ecotype of Choutrana is rich in linoleic acid. Unsaturated fatty acids ranged from 40.4% to 44.4% of the total fatty acids for each ecotype. The ratio of the poly-unsaturated/saturated (P/S) varied from 9.6 to 10.1 in all ecotypes. Five major sterols have been identified. The β-sitosterol is the prominent component in all the ecotypes and the highest level is found in the Sfax ecotype. Stigmasterol is more abundant in Sfax and Choutrana ecotypes. Campesterol is important in Choutrana seeds. Copyright © 2012 Société botanique de France.


Chouchaine M.,Commissariat Regional du Developpement Agricole de Sidi Bouzid | Barbouche N.,Institute National Agronomique Of Tunisie | Khemiri A.,Institute Sylvo Pastoral Of Tabarka
Livestock Research for Rural Development | Year: 2015

To study the biodiversity Apis mellifera intermissa in Tunisia, surveys were conducted at five locations, 4 in the norther part, and 1 in the center. This study was conducted on four haplotypes (A1, A4, A8 and A9) in their area of origin, except haplotypes A4 and A9 Ouled Haffouz. This study focused on the study of the microclimate of the Tunisian bee namely, temperature thermopréférendum, laying, cleaning and shape of the brood. It was conducted on 100 colonies, 25 colonies for each haplotype. There is a difference between the internal temperatures of haplotypes. The temperature of the brood nest haplotypes A1 and A8 is around 36°C against the temperature of the brood nest haplotypes A9 and A4 is less than 2°C of the haplotype A1 and A8. When weather conditions are extreme, only haplotypes A4 and A9 come into hibernation, the temperature of the brood nest is of the order of (25 ± 3°C). By analogy, the haplotypes A1 and A8 have a high spawn regardless of weather trend. For cons, the haplotypes A9 and A4, they tend to lay are variable ranging from zero to average depending on weather conditions. Regardless of the type of haplotype and climatic conditions, the Tunisian bee is endowed with a very strong hygienic. The difference in the rate of recovery of spawning after the test cleaning four haplotypes is attributed to physiological factor of these bees. It is due to the biochemical variability sequence at the intergenic region of the CIO-COII four haplotypes of mitochondrial DNA. So the Tunisian bee halotypes are well adapted to their local climatic conditions. © 2015 Fundacion CIPAV. All rights reserved.


Elaloui M.,Institute National des Recherches en Genie Rural | Laamouri A.,Institute National des Recherches en Genie Rural | Fabre J.,ENSIACET | Mathieu C.,ENSIACET | And 2 more authors.
Natural Product Research | Year: 2015

Ziziphus jujuba pulps are very much appreciated by the inhabitants and have been recently exported. This article reports on the chemical composition (amino acids, polyphenols and sugars) of the pulps of four Z. jujuba ecotypes (Choutrana, Mahdia, Mahres and Sfax). The major amino acids identified were proline, aspartic acid and glutamic acid. Among these, proline was the most abundant amino acid (17.4 mol). Considerable differences in total phenolic contents (15.85 mg/L) were found. Predominant phenols identified by using HPLC were rutin (1.09 mg/L) and chlorogenic acid (2.57 mg/100 g). Sugars isolated from Ziziphus pulps were found at a rate of 43.52%. Using HPLC method, three sugars from the pulp extract were identified: glucose, galactose and sucrose. The Mahdia ecotype was the richest in these sugars with 0.45, 136.51 and 113.28 mg/L, respectively. © 2015 Taylor & Francis.


Elaloui M.,Institute National des Recherches en Genie Rural | Laamouri A.,Institute National des Recherches en Genie Rural | Albouchi A.,Institute National des Recherches en Genie Rural | Cerny M.,ENSIACET | And 3 more authors.
Emirates Journal of Food and Agriculture | Year: 2014

Thirteen fatty acids were identified from the pulps of four Tunisian Ziziphus jujuba ecotypes (Sfax, Choutrana, Mahres and Mahdia), using capillary gaseous chromatography method. These oils presented 8.31% to 12.35% of dry weights. Compared to the other ecotypes, Mahres and Choutrana were the richest of the oleic acid. The palmitic acid was the most important compound of the Sfax ecotype. Unsaturated fatty acids ranged from 62.63% to 72.40% of the total fatty acids of each ecotype. So a ratio of the unsaturated/saturated (U/S) varied from 1.68 to 2.37. The β-sitosterol and the Stigmasterol were identified as major sterols. The β-sitosterol was the prominent component in the all ecotypes and the highest level (10.65 mg/100g) was noted in Choutrana ecotype. Stigmasterol was more abundant in Sfax (16.12 mg/100g) and Choutrana (4.67 mg/100g) ecotypes. The campesterol sterol was identified only in Sfax and Choutrana ecotypes being more important (2.4 mg/100g) in Choutrana pulps.


Mechergui T.,University of Carthage | Pardos M.,Instituto Nacional Of Investigacion Y Tecnologia Agraria Y Alimentaria Inia | Boussaidi N.,Institute Sylvo Pastoral Of Tabarka | Hasnaoui B.,Purdue University | Jacobs D.F.,Purdue University
Journal of Forestry Research | Year: 2013

The need for reforestation in cork oak (Quercus suber L.) areas is challenged by difficulties. Principal among these is herbivory of young plants, vegetative competition, and slow growth rates of cork oak seedlings. We evaluated the early development of cork oak seedlings treated using tree shelters and mulching in northwestern Tunisia. We tested three tree shelter treatments (non-vented, vented, and control) to shield seedlings from animal damage and five mulch types to control competing vegetation (Italian Stone Pine, Lentisk, combination of Italian Stone Pine and Lentisk (organic mulches), gravel (inorganic mulch) and no mulch). At the end of the two-year experiment, sheltered seedlings were 89-99% taller than unsheltered seedlings and had higher numbers and lengths of shoot growth flushes. In contrast, both stem diameter growth and dry weight biomass (from samples extracted after two years) were significantly reduced inside tree shelters. Root-to-shoot ratio was not significantly different in sheltered vs. unsheltered seedlings, suggesting that tree shelters do not adversely affect this parameter. Mulching alone did not favour growth, but could be beneficial when combined with tree shelters. The combination of vented tree shelters and gravel mulch was the most effective treatment for promoting diameter, height and stem volume growth. © 2013 Northeast Forestry University and Springer-Verlag Berlin Heidelberg.


Chakroun H.,Tunis el Manar University | Mouillot F.,EPHE Paris | Hamdi A.,Institute Sylvo Pastoral Of Tabarka
Remote Sensing | Year: 2015

The performance of vegetation indexes derived from moderate resolution imaging spectroradiometer (MODIS) sensors is explored for drought monitoring in the forests of Northern Tunisia; representing a transition zone between the Mediterranean Sea and the Sahara Desert. We investigated the suitability of biomass and moisture vegetation indexes for vegetation water content expressed by the equivalent water thickness (EWT) in a Mediterranean forest ecosystem with contrasted water budgets and desiccation rates. We proposed a revised EWT at canopy level (EWTCAN) based on weekly field measurements of fuel moisture in seven species during the 2010 dry period; considering the mixture of plant functional types for water use (trees; shrubs and herbaceous layers) and a varying vegetation cover. MODIS vegetation indexes computed and smoothed over the dry season were highly correlated with the EWTCAN. The performances of moisture indexes (Normalized Difference Infrared Index (NDII6 and NDII7); and Global Moisture Vegetation Index (GVMI6 and GVMI7)) were comparable; whereas; for biomass vegetation indexes; Normalized Difference Vegetation Index (NDVI); Modified Soil Adjusted Vegetation Index (MSAVI) and Adjusted Normalized Difference Vegetation Index (ANDVI) performed better than Enhanced Vegetation Index (EVI) and Soil Adjusted Vegetation Index (SAVI). We also identified the effect of Leaf Area Index (LAI) on EWTCAN monitoring at the regional scale under the tree cover/LAI gradient of the region from relatively dense to open forest. Statistical analysis revealed a significant decreasing linear relationship; indicating that for LAI less than two; the greater the LAI; the less responsive are the vegetation indexes to changes in EWTCAN; whereas for higher LAI; its influence becomes less significant and was not considered in the inversion models based on vegetation indexes. The EWTCAN time-course from LAI-adapted inversion models; based on significantly-related vegetation indexes to EWTCAN; showed close profiles resulting from the inversion models using NDVI; ANDVI; MSAVI and NDII6 applied during the dry season. The developed EWTCAN model from MODIS vegetation indexes for the study region was finally tested for its ability to capture the topo-climatic effects on the seasonal and the spatial patterns of desiccation/rewetting for keystone periods of Mediterranean vegetation functioning. Implications for further use in scientific developments or management are discussed.


Arfaoui M.O.,Laboratoire Of Biochimie Des Lipides | Renaud J.,University of Ottawa | Ghazghazi H.,Institute Sylvo Pastoral Of Tabarka | Boukhchina S.,Laboratoire Of Biochimie Des Lipides | Mayer P.,University of Ottawa
Natural Product Research | Year: 2014

This study has determined oil, fatty acid (FA) and phytosterols content during the ripening of the Tunisian Onopordum acanthium L. seeds. In total, nine FAs and six phytosterols were identified. The main FAs were linoleic acid (0.18-8.06 mg/g of seed) followed by oleic acid (0.051-2.45 mg/g of seed), palmitic acid and stearic acid. Pentadecanoic acid was detected, for the first time, in unripe fruits and the two last stages of development were characterised by a relative abundance of erucic acid. Overall, β-sitosterol (34.5-77.79% of total sterols) was the major 4-desmethylsterols during maturation. The first episodes of growth were characterised by the best amounts of stigmasterol and campesterol, while stigmastanol and Δ7 sitosterol had quoted the semi-ripe and fully ripe fruits; however, cholesterol was absent. These findings are useful in understanding a potential new source of important natural compounds (Phytosterols and USFA) found in this fruit and when harvest should be undertaken to optimise desired FA and phytosterols content. © 2014 Taylor & Francis.

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