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See detailNutritional and organoleptic quality of Beni-Guil lamb meat breeding in eastern Morocco
Belhaj, Kamal ULiege; Mansouri, Farid; Sindic, Marianne ULiege et al

Poster (2017, April 27)

Nowadays in Morocco, 98% of red meat production is ensured by cattles, sheeps and goast. The eastern Morocco represents one of the main sheep farming areas, characterized by the specificity of its ... [more ▼]

Nowadays in Morocco, 98% of red meat production is ensured by cattles, sheeps and goast. The eastern Morocco represents one of the main sheep farming areas, characterized by the specificity of its production systems. So it is well known by the quality of the sheep meat produced. The Beni-Guil breed is a dominate breed in this breeding area, labeled Protected Geographical Indication (PIG). Thus, it’s an important protein source for the population in this geographical site and highly appreciated by consumers. This reputation is limited to the hedonic quality, and there is currently no scientific data available on the organoleptic and nutritional quality of Beni-Guil meat. The objective of this research is to give a scientific point on the nutritional and organoleptic quality of this meat by biochemical analyzes of the major and minor composition of the Longissimus dorsi muscle (LDM). The results of the organoleptic quality analysis show that the meat of Beni-Guil breed has a bright red color, with a chromaticity of 23.97, an a/b ratio of 0.96 and a hue angle of 46.47, Significant juiciness with a water retention capacity and cooking loss of 22.73 and 32.87% respectively, and a marked tenderness with a collagen content of 0.1%. Thus the analysis of nutritional quality showed that LDM of the Beni-Guil has a high nutritional and dietary value, rich in polyunsaturated fatty acid (PUFA) and essential amino acid, with an PUFA/SFA ratio of 0.25, a ratio PUFA n-6/PUFA n-3 of 3.78, and a Protein Digestibility-Corrected Amino Acid score (PDCAAS) of 127. [less ▲]

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See detailProfil d'acides gras et stabilité oxydative d'huiles de brisures d'amandons et d'écarts de tri des amandes
Houmy, Nadia ULiege; Melhaoui, R; Sindic, Marianne ULiege et al

Conference (2017, April 27)

Dans la région orientale du Maroc, en outre du projet *PROFAO, la filière Amandier bénéficie d'une attention particulière. Cependant, les opérations de concassage et de triage des amandes se font encore ... [more ▼]

Dans la région orientale du Maroc, en outre du projet *PROFAO, la filière Amandier bénéficie d'une attention particulière. Cependant, les opérations de concassage et de triage des amandes se font encore de façon artisanale. Dans un but de valorisation après le décorticage/concassage, les brisures et les écarts de tri des amandes, ayant une faible valeur marchande, servent à l'extraction d'huile pour usage alimentaire et cosmétique. Ce travail porte sur l'analyse chimique d'huiles de brisures d'amandes (HbA) et la détermination de leur stabilité oxydative. Ainsi sur trois compagnes agricoles consécutives 2014, 2015, 2016, des analyses par CPG FID des profils d'acides gras (AG) des HbA des variétés Marcona Ferragnes-Ferraduel, ont été effectuées. L'acide Oléique (C18:1) et l'acide Linoléique (C18:2) sont les deux AG majoritaires qui caractérisent les profils d'AG des HbA. Selon l'année de récolte, ces HbA ont montré des variations inter variétale, les différences observées sont significatives et sont de l'ordre de 15 % pour C18:1 et de 13 % pour C18:2. Ainsi la teneur des HbA analysées en C18:1 varie entre un taux-max de 72 % enregistré en 2013/2014 pour Ferrangnes-Ferraduel et un taux-minima de 57 % observé en 2015/2016 pour Marcona. La même remarque pour le C18:2 avec une teneur minimum de 17 % enregistré en 2013/2014 pour Ferragnes-Ferraduel et une teneur maximum de 30 % observé en 2015/2016 pour Marcona. Pour le rapport O/L la plus grande différence a été observée en 2013/2014, avec un ratio O/L de 4,1 pour l'HbA Ferragnes-Ferraduel et de 1,95 pour Marcona. Les résultats observés pour la stabilité oxydative des Hba estimée par des tests Rancimat montrent des valeurs qui varient entre un minimum de 20h pour l'HbA Marcona en 2013/2014 et un maximum de 29h pour l'HbA Ferragnes Ferraduel en 2015/2016. On note une corrélation positive entre la stabilité oxydative et la teneur des HbA en C18:1 ainsi qu'avec le ratio O/L. La suite logique de ce travail est la recherche d'une correlation entre la stabilité oxydative et les composants mineurs de l'huile notamment ceux à activité antioxydante tel les tocophérols. [less ▲]

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See detailSalinity impact on seed yield, polyphenols composition and antioxidant activity of Fennel (Foeniculum vulgarae Mill) extracts
Bettaieb Rebey, Ines; Bourgou, S.; Msaada, K. et al

Poster (2017, April 24)

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See detailEtude de la composition chimique et de l’activité antioxydante des différents extraits de la Lavande dentée (Lavandula dentata)
Bettaieb Rebey, I.; Bourgou, S.; Saidani Tounsi, M. et al

in Journal of New Sciences Agri & Biotech (2017), 39(2), 2096-2105

In this study, Lavandula dentata organs (roots, stems and leaves) were investigated for their essential oils, total phenolics, flavonoids contents and antioxidant activities. Essential oil yields were 0 ... [more ▼]

In this study, Lavandula dentata organs (roots, stems and leaves) were investigated for their essential oils, total phenolics, flavonoids contents and antioxidant activities. Essential oil yields were 0.22% in roots, 0.68 % in stems and 0.89 % in flowers. Major components of the oils were β-ocimene, limonene and 1,8 cineol in roots, stems and leaves and flowers, respectively. In all organs, total phenolics content ranged from 42.57 to 16.17 mg gallic acid equivalents per gram of dry weight (mg GAE/g DW).The antioxidant activities of Lavandula dentata extracts obtained from the three organs were assessed using two tests (DPPH and reducing power). The root extract was strongly effective as DPPH radical scavenger and reducing agent. Thus, the identification of individual target polyphenolic compounds of roots was performed by RP-HPLC. The major phenolic compound detected in roots was rosmarinic acid. This activity was high enough for the plant to be a new and natural source of strongly antioxidant substances for use as natural additives in food and pharmaceutical industry. [less ▲]

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See detailQuality and chemical composition of longissimus dorsi muscle of Béni-Guil sheep breeding in eastern Morocco
Belhaj, Kamal ULiege; Mansouri, Farid; Ben-Moumen, Abdessamad et al

Poster (2017, February 07)

The aim of the present study was to analyze the lipid, cholesterol, fatty acids composition and amino acids from red meat of Béni-Guil sheep breeding in eastern of Morocco, which was breeded in semi ... [more ▼]

The aim of the present study was to analyze the lipid, cholesterol, fatty acids composition and amino acids from red meat of Béni-Guil sheep breeding in eastern of Morocco, which was breeded in semi-extensive breeding, Its very appreciated by the consumer, but this good reputation is still only on Informal Hedonic Tests, the Consumers speak about the best sheep meat as regards the quality and intensity of its aroma and succulence, flavour and tenderness. The objective of this research is to evaluate the nutritional, organoleptic and health quality of this meat by biochemical analyzes, in particular the cholesterol, fatty acid profile (FA) and amino acid composition of the longissumus dorsi muscle. Meat quality was measured on the longissimus dorsi (LD). The results showed that 100g of fresh meat contains 25.72% of dry matter, including 5.14% of Fat, 19.43% of protein and 0.94% of mineral matter. The fatty acid profile measured showed that 100 grams of fat contains 24.98 grams fatty acids, including 49.45% saturated fatty acid, 38.48% monounsaturated fatty acid and 12.40% polyunsaturated fatty acid. Qualitative and quantitative analyses of amino acids composition allowed the identification of more than 18 components including six essential amino acids (Ile, Leu Lys, Thr, Val, Phe). [less ▲]

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See detailUse of complementary biophysical approaches to study the interactions of fatty acid hydroperoxides with biomimetic plant plasma membranes
Deboever, Estelle ULiege; Nasir, Mehmet Nail ULiege; Deleu, Magali ULiege et al

Poster (2017, January 20)

In the actual context, biopesticides have emerged as a main alternative to conventional agriculture1. Hence, elicitors are metabolites naturally produced by microorganisms, pathogenic or not, and plants ... [more ▼]

In the actual context, biopesticides have emerged as a main alternative to conventional agriculture1. Hence, elicitors are metabolites naturally produced by microorganisms, pathogenic or not, and plants which are able to induce the natural resistance of plants. Also, they have proved to be excellent candidates for biological control. In this context, the lipoxygenase pathway leads to the formation of fatty acid degradation products, called oxylipins, which appear to be crucial agents in plant defence mechanisms2,3. Moreover, with their broad spectrum of action and their possible inducibility, oxylipins appear to be promising candidates for their use as elicitors4. This work focuses on two hydroperoxy-derived oxylipins, the 13(S)-hydroperoxy-octadecadienoic acid (13-HPOD) and the 13(S)-hydroperoxy-octadecatrienoic acid (13-HPOT). The study of the interaction of such compounds with representative plant plasma membrane lipids is essential to understand plant resistance mechanisms. Several in silico and experimental techniques of biophysics showed that acyl-hydroperoxides have significant adsorption capacity and a strong affinity for model membranes. They may also penetrate biological membrane but no permeabilisation effect was observed in this work. Slight conformational differences seem to have a significant impact on their ability to interact with plant plasma membranes. Based on these results, further investigation of the interactions of fatty acids hydroperoxides, even more on the 9-forms, with plant plasma membranes and eventually in the presence of phytopathogenic species, would allow a better understanding of the innate immunity and, on the longer term, could lead to the development of new elicitors with biological mechanisms potentially independent of membrane protein receptors. [less ▲]

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See detailDifferential interaction of synthetic glycolipids with biomimetic plasma membrane lipids correlates with plant biological response
Nasir, Mehmet Nail ULiege; Lins, Laurence ULiege; Crowet, Jean-Marc ULiege et al

in Langmuir (2017)

Natural and synthetic amphiphilic molecules including lipopeptides, lipopolysaccharides and glycolipids are able to induce defense mechanisms in plants. In the present work, the perception of two ... [more ▼]

Natural and synthetic amphiphilic molecules including lipopeptides, lipopolysaccharides and glycolipids are able to induce defense mechanisms in plants. In the present work, the perception of two synthetic C14 rhamnolipids, namely Alk-RL and Ac-RL, differing only at the level of the lipid tail terminal group, have been investigated using biological and biophysical approaches. We showed that Alk-RL induces a stronger early signaling response in tobacco cell suspensions than does Ac-RL. The interactions of both synthetic RLs with simplified biomimetic membranes were further analyzed using experimental and in silico approaches. Our results indicate that the interactions of Alk-RL and Ac-RL with lipids were different in terms of insertion and molecular responses and were dependent on the lipid composition of model membranes. A more favorable insertion of Alk-RL than Ac-RL into lipid membranes is observed. Alk-RL forms more stable molecular assemblies than Ac-RL with phospholipids and sterols. At the molecular level, the presence of sterols tends to increase the RLs’ interaction with lipid bilayers with a fluidizing effect on the alkyl chains. Taken together, our findings suggest that the perception of these synthetic RLs at the membrane level could be related to a lipid-driven process depending on the organization of the membrane and the orientation of the RLs within the membrane and is correlated with the induction of early signaling responses in tobacco cells. [less ▲]

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See detailChemical Composition of Distilled Essential Oils and Hydrosols of Four Senegalese Citrus and Enantiomeric Characterization of Chiral Compounds
Ndiaye, El Hadji Barka; Gueye, Momar Talla; Ndiaye, Ibrahima et al

in Journal of Essential Oil-Bearing Plants [=JEOBP] (2017), 20(3), 820-834

Peels of four local Citrus species (Citrus sinensis L. Obsbeck, Citrus reticulata Blanco, Citrus maxima Burm. and Citrus aurantifolia christm.) grown in a same locality under the same climatic conditions ... [more ▼]

Peels of four local Citrus species (Citrus sinensis L. Obsbeck, Citrus reticulata Blanco, Citrus maxima Burm. and Citrus aurantifolia christm.) grown in a same locality under the same climatic conditions were subjected to steam distillation. The essential oils and floral waters obtained were analyzed by gas chromatography coupled with a flame ionization detector (CPG-FID) and by gas chromatography coupled to a mass spectrometer (CPG-MS). The essential oils yields were ranged between 0.2 and 0.7 %. The qualitative and quantitative analyses show 74 compounds in all oils samples. The oils were largely dominated by hydrocarbon monoterpenes with limonene as major compound (91.5-94.0 %; 90.4-93.4 %; 77.7-93.7 % and 34.8-51.2 %) in oils from Citrus sinensis, Citrus reticulata, Citrus maxima and Citrus aurantifolia, respectively. In addition to limonene, oils of Citrus aurantifolia contained high amounts of β-pinene (6.8-14.4 %), pcymene (5.8-12.2 %), γ-terpinene (0.3 -7.4 %), neral (1.5-9.4 %), geraniol (1.9-12.7 %). Although presenting the same major compound (limonene), the oils had compositions that were qualitatively and quantitatively different. The enantiomeric analyses showed that the chiral major compounds were (R) - (+) - limonene, (S) - (-) – limonene, (1S) - (-) -β-pinene, (1R)-(+)-β-pinene and (S) - (+) - carvone. The hydrosols analyzed were composed of oxygenated compounds and did not have the same major compound. A qualitative and quantitative difference in chemical composition was noted between the Hydrosols. [less ▲]

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See detailGamification croissante d’un quiz de chimie – Effets comparés sur la performance, la perception de compétence et l’état de flow
le Maire, Nathalie ULiege; Dalcq, Anne-Catherine ULiege; Colaux, Catherine ULiege et al

in Revue Internationale des Technologies en Pédagogie Universitaire = International Journal of Technologies in Higher Education (2017), 14(1), 69-83

Mini-games have recently emerged in the literature on gamification as an affordable alternative to immersive serious games. The present study aims to evaluate the effects of the use of chemistry minigames ... [more ▼]

Mini-games have recently emerged in the literature on gamification as an affordable alternative to immersive serious games. The present study aims to evaluate the effects of the use of chemistry minigames having a growing gamification on the performance, the self-confidence and the flow perceived by first year bioengineering students. Results indicate no effect on the first two parameters but show a positive effect on four dimensions of the flow. Given these mixed results, the conditions of an effective use of mini-games with undergraduate students are then discussed. [less ▲]

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See detailEvaluation of different hydrocolloids to improve dough rheological properties and bread quality of potato-wheat flour
Liu, Xingli ULiege; Mu, Taihua; Yamul, Karim Diego et al

in Journal of Food Science and Technology (2017), 54(6), 15971607

The aim of study was to investigate the effect of hydroxylpropylmethylcellulose (HPMC), arabic gum (AG), konjac glucomannan (KG) and apple pectin (AP) at 2% (w/w, potato-wheat flour basis) on the potato ... [more ▼]

The aim of study was to investigate the effect of hydroxylpropylmethylcellulose (HPMC), arabic gum (AG), konjac glucomannan (KG) and apple pectin (AP) at 2% (w/w, potato-wheat flour basis) on the potato-wheat dough (the mass ratio was 1:1) rheological, fermentation properties and its bread quality. The tan δ of potato-wheat dough was significantly increased by adding HPMC compared to those of without adding hydrocolloids (from 0.337 to 0.425), which was close to wheat dough (0.531). Moreover, the dough height during fermentation process was significantly improved by adding hydrocolloids, with the order of HPMC (23.1mm) > AP (19.3mm) > AG (18.6mm) > KG (13.6mm). In addition, the potato-wheat protein bands of potato-wheat dough turned pale by adding hydrocolloids, suggesting higher molecular weight aggregation formed between proteins-hydrocolloids or proteins-proteins after fermentation process. Furthermore, HPMC significantly increased specific volume (from 1.45 to 2.22 ml/g), and hydrocolloids restrained the starch retrogradation of potato-wheat breads. [less ▲]

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See detailPlant Oxylipins: Structure-function Relationships
Genva, Manon ULiege; Andersson, Mats X.; Nasir, Mehmet Nail ULiege et al

Poster (2017)

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See detailChemical composition, acute toxicity, antimicrobial and anti-inflammatory activities of Thymus fontanesii essential oil from Algeria
Sidali, Lamia; Brada, Mousa; Fauconnier, Marie-Laure ULiege et al

in PhytoChem & BioSub Journal (2017), 11(1), 11

The aim of the present study was to determine the chemical composition and to evaluate the acute toxicity, antimicrobial and anti-inflammatory activities of Thymus fontanesii essential oils (TFEO). The ... [more ▼]

The aim of the present study was to determine the chemical composition and to evaluate the acute toxicity, antimicrobial and anti-inflammatory activities of Thymus fontanesii essential oils (TFEO). The oils were obtained by hydrodistillation from the aerial parts of T. fontanesii at yield of 2.4±0.2%. Using GC and GC/MS techniques, 24 compounds were identified representing more than 98% of the oil composition. The main constituents were carvacrol (54.7±1.2%), p-cymene (17.5±0.3%) and ɣ-terpinene (8.8±0.6%). Using the disc diffusion and broth microdilution methods against six microbial strains, the antimicrobial evaluation showed that TFEO exhibited good antibacterial activity against all the strains tested except Pseudomonas aeruginosa. The acute toxicity test of TFEO was conducted in mice by gavage in single doses of 100-3000 mg/kg. However, the mortality rate as well as the acute toxicity of the oral administered oil increased progressively with increasing dose (LD50=875mg/kg). Anti-inflammatory activity of TFEO was evaluated using carrageenaninduced paw edema in mice. The paw edema was reduced by the TFEO at doses of 50 mg/kg (22.8%) and 100 mg/kg (62.2%). The TFEO was found to possess potent anti-inflammatory activity.Results of the present study indicate that TFEO has a noteworthy potential for the use in pharmaceutical formulations. [less ▲]

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See detailChemical composition of essential oils and hydrosols of three Eucalyptus species from Senegal: Eucalyptus alba Renv, Eucalyptus camaldulensis Dehnh and Eucalyptus tereticornis Hook
Barka Ndiaye, El Hadji; Talla Gueye, Momar; Ndiaye, Ibrahima et al

in American Journal of Essential Oils and Natural Products (2017), 5(1), 1-7

The leaves of three eucalyptus species Eucalyptus Alba, Eucalyptus camaldulensis and ucalyptus tereticornis were collected in Kaolack (Senegal) and were extracted by steam distillation after 3, 7, 14 and ... [more ▼]

The leaves of three eucalyptus species Eucalyptus Alba, Eucalyptus camaldulensis and ucalyptus tereticornis were collected in Kaolack (Senegal) and were extracted by steam distillation after 3, 7, 14 and 21 days of drying. The volatile components of aqueous distillates (hydrosols) were obtained by liquid–liquid extraction using n-hexane. The different extracts were analyzed by gas chromatography coupled to a flame ionization detector (GC-FID) and by gas chromatography coupled to a mass spectrometer (GC-MS). Essential oils yields obtained range from 0.3 to 1.6%. E. camaldulensis had the higher yield. Forty four compounds were characterized in E. camaldulensis essential oils. These lasts were dominated by 1.8-cineole (47.54 to 52.47%), limonene (16.5 to 19.1%), α-pinene (7.3 to 11.2%) and p-cymene (6.0 to 8.8%). Fifty compounds were identified in E. Alba oils with 1.8-cineole (36.0-38.3%) α-pinene (19.0-26.4%), limonene (5.7- 8.3%), trans-pinocarveol (3.5 -5.0%) β-pinene (1.9 to 4.6%) as major compounds. In E. tereticornis oils, fifty two compounds were identified. Their composition were dominated by p-cymene (42.49 to 48.51%) followed by 1.8-cineole (21.3- 24.5%), limonene (4.8- 5.9%) and α-pinene (1.9 to 6.7%). The analyzed hydrosols were composed by oxygenated molecules whose major part was found in oils. As essential oils, all corresponding hydrosols hade high rate of 1.8-cineole. E. alba hydrosol contains mainly 1.8-cineole (39.1%), trans-pinocarveol (19.3%), pinocarvone (6.8%). E. camaldulensis hydrosol was dominated by 1.8-cineole (52.6%), α-terpineol (6.6%), cis-p-mentha-1-(7)-8-dien-2ol (5.1%). The major compounds of E. tereticornis hydrolat were: 1.8-cineole (30.7%), α-terpineol (8.8%), trans-pinocarveol (7.6%), carvacrol (7.0%). The results showed that although 1.8-cineole was the main component of the hydrosols of all eucalyptus species, but its relative content was higher in E. camaldulensis. [less ▲]

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See detailFlavor profiles of monovarietal virgin olive oils produced in the Oriental region of Morocco
Mansouri, Farid; Ben Moumen, Abdessamad; Richard, Gaetan ULiege et al

in Oilseeds and fats, Crops and Lipids (2017), 24

The purpose of this study is the evaluation of flavor profiles of monovarietal virgin olive oils (VOO) produced in the Oriental region of Morocco via the characterization of volatile compounds, using SPME ... [more ▼]

The purpose of this study is the evaluation of flavor profiles of monovarietal virgin olive oils (VOO) produced in the Oriental region of Morocco via the characterization of volatile compounds, using SPME-GC/MS technique, and the determination of total phenolic content (colorimetric method). The study concerns oils of three European olive cultivars (Arbosana, Arbequina and Koroneiki) which were recently introduced in Morocco under irrigated high-density plantation system. GC/MS aroma profiles of analyzed VOOs showed the presence of 35 volatile compounds. The major compounds in such oils are C6 compounds produced from linoleic and linolenic acids via lipoxygenase pathway such as trans-2-hexenal, cis-2-hexenal, cis-3-hexen-1-ol, trans-3-hexen-1-ol, trans-3-hexen-1-ol acetate, hexanal and 1-hexanol in different proportions depending on the cultivar (p<0.05). In addition, statistical analyses indicate that the analyzed VOOs have different aroma profiles. Arbequina oil has a high proportion of compounds with sensory notes “green” and “sweet” giving it a fruity sensation compared to Arbosana and Koroneiki. In parallel, Arbosana and Koroneiki oils are rich in phenolic compounds and provide relatively bitter and pungent tastes to these oils. [less ▲]

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See detailPhytotoxic activity and chemical composition of Cassia absus seeds and aerial parts
Zribi, Ines; Sbai, H.; Ghezal, N. et al

in Natural Product Research (2017)

The present study was conducted to assess the phytotoxic potential and the phytochemical composition of Cassia absus. Aqueous extracts caused significant reduction of root growth of Lactuca sativa. Seed ... [more ▼]

The present study was conducted to assess the phytotoxic potential and the phytochemical composition of Cassia absus. Aqueous extracts caused significant reduction of root growth of Lactuca sativa. Seed extract was more effective than aerial part extract. Successive extractions of this plant were performed using solvents with increasing polarities. The methanolic seed extract exerted strong phytotoxic effect on seedling growth, followed by petroleum ether extract of the aerial part. The phytochemical investigation showed that among the organic extracts, methanol extracts of seeds and aerial parts contained the highest amounts of total phenolics and proanthocyanidins. Seeds were rich in linoleic acid followed by palmitic acids. Palmitic, stearic and arachidic acids were the major fatty acids in aerial parts. HPLC-DAD analysis of the methanolic extracts revealed the presence of luteolin in C. absus aerial parts. [less ▲]

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See detailMethanol emissions from maize: Ontogenetic dependence to varying light conditions and guttation as an additional factor constraining the flux
Mozaffar, Ahsan ULiege; Schoon, N.; Digrado, Anthony ULiege et al

in Atmospheric Environment (2017), 152

Because of its high abundance and long lifetime compared to other volatile organic compounds in the atmosphere, methanol (CH3OH) plays an important role in atmospheric chemistry. Even though agricultural ... [more ▼]

Because of its high abundance and long lifetime compared to other volatile organic compounds in the atmosphere, methanol (CH3OH) plays an important role in atmospheric chemistry. Even though agricultural crops are believed to be a large source of methanol, emission inventories from those crop ecosystems are still scarce and little information is available concerning the driving mechanisms for methanol production and emission at different developmental stages of the plants/leaves. This study focuses on methanol emissions from Zea mays L. (maize), which is vastly cultivated throughout the world. Flux measurements have been performed on young plants, almost fully grown leaves and fully grown leaves, enclosed in dynamic flow-through enclosures in a temperature and light-controlled environmental chamber. Strong differences in the response of methanol emissions to variations in PPFD (Photosynthetic Photon Flux Density) were noticed between the young plants, almost fully grown and fully grown leaves. Moreover, young maize plants showed strong emission peaks following light/dark transitions, for which guttation can be put forward as a hypothetical pathway. Young plants’ average daily methanol fluxes exceeded by a factor of 17 those of almost fully grown and fully grown leaves when expressed per leaf area. Absolute flux values were found to be smaller than those reported in the literature, but in fair agreement with recent ecosystem scale flux measurements above a maize field of the same variety as used in this study. [less ▲]

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See detailChemical composition, vasorelaxant, antioxidant and antiplatelet effects of essential oil of Artemisia campestris L. from Oriental Morocco
Dib, Ikram; Fauconnier, Marie-Laure ULiege; Sindic, Marianne ULiege et al

in BMC Complementary and Alternative Medicine (2017), 17(art. 82), 1-15

Background: Artemisia campestris L. (Asteraceae) is a medicinal herb traditionally used to treat hypertension and many other diseases. Hence, this study is aimed to analyze the essential oil of A ... [more ▼]

Background: Artemisia campestris L. (Asteraceae) is a medicinal herb traditionally used to treat hypertension and many other diseases. Hence, this study is aimed to analyze the essential oil of A. campestris L (AcEO) and to investigate the antiplatelet, antioxidant effects and the mechanisms of its vasorelaxant effect. Methods: The chemical composition of AcEO was elucidated using GC/MS analysis. Then, the antioxidant effect was tested on DPPH radical scavenging and on the prevention of β-carotene bleaching. The antiplatelet effect was performed on the presence of the platelet agonists: thrombin and ADP. The mechanism of action of the vasorelaxant effect was studied by using the cellular blockers specified to explore the involvement of NO/GC pathway and in the presence of calcium channels blockers and potassium channels blockers. Results: AcEO is predominated by the volatiles: spathulenol, ß-eudesmol and p-cymene. The maximal antioxidant effect was obtained with the dose 2 mg/ml of AcEO. The dose 1 mg/ml of AcEO showed a maximum antiplatelet effect of, respectively 49.73% ±9.54 and 48.20% ±8.49 on thrombin and ADP. The vasorelaxation seems not to be mediated via NOS/GC pathway neither via the potassium channels. However, pretreatment with calcium channels blockers attenuated this effect, suggesting that the vasorelaxation is mediated via inhibition of L-type Ca2+ channels and the activation of SERCA pumps of reticulum plasma. Conclusion: This study confirms the antioxidant, antiplatelet and vasorelaxant effects of A.campestris L essential oil. However, the antihypertensive use of this oil should be further confirmed by the chemical fractionation and subsequent bio-guided assays. [less ▲]

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See detailChemical Composition and Acaricidal Activity of Thymus algeriensis Essential Oil against Varroa destructor
Kouache, Benmoussa; Brada, Moussa; Saadi, Abdelkader et al

in Natural Product Communications (2017), 12(0), 1-4

The aim of the present study was to determine the chemical composition and evaluate the acaricidal activity of Thymus algeriensis essential oil (TAEO) against Varroa destructor. This ectoparasitic mite is ... [more ▼]

The aim of the present study was to determine the chemical composition and evaluate the acaricidal activity of Thymus algeriensis essential oil (TAEO) against Varroa destructor. This ectoparasitic mite is a pest of the honey bee Apis mellifera. The essential oil from the aerial parts of T. algeriensis, obtained by hydrodistillation, was obtained in a yield of 2.8± 0.2%, w/w. The TAEO was analyzed by GC and GC/MS. Thirty-four compounds were identified, representing 99.3% of the oil. The main constituents were carvacrol (48.4%), γ-terpinene (14.9%), p-cymene (14.7%), and thymol (5.6%). Four lots were constituted at the level of an apiary in order to study the dynamics of the Varroa destructor and its host, Apis mellifera. After diagnosis by the biological method "install of diapers", the lots were treated at different doses of TAEO (0.1, 0.3 and 0.5%). TAEO was sprayed on top of the hives. The results show that TAEO at 0.5% resulted in a decrease in the rate of infestation of Varroa destructor, causing a mortality rate of 32.6% without negative effect on the nesting of the queen. The essential oil of T. algeriensis could be used as a bioacaricidal agent. [less ▲]

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