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41.
Lipase-assisted generation of 2-methyl-3-furanthiol and 2-furfurylthiol from thioacetates 总被引:2,自引:0,他引:2
Bel Rhlid R Matthey-Doret W Blank I Fay LB Juillerat MA 《Journal of agricultural and food chemistry》2002,50(14):4087-4090
Enzymatic hydrolysis of S-3-(2-methylfuryl) thioacetate and S-2-furfuryl thioacetate using lipase from Candida rugosa produced 2-methyl-3-furanthiol and 2-furfurylthiol, respectively. When reactions were carried out at room temperature and pH 5.8, 2-methyl-3-furanthiol was produced in a optimal yield of 88% after 15 min of reaction, whereas 2-furfurylthiol was obtained in a yield of 80% after 1 h of reaction time. Enzymatic hydrolysis was also performed in n-hexane, n-pentane, and water/propylene glycol mixture. The reaction rates in these media were slower as compared to those in aqueous medium; however, the reaction yields were quite similar. As expected, the stability of the generated 2-methyl-3-furanthiol and 2-furfurylthiol was better in n-hexane, n-pentane, and the water/propylene glycol mixture as compared to that in water or phosphate buffer. 相似文献
42.
Long-term changes in soil organic matter under conventional tillage and no-tillage systems in semiarid Morocco 总被引:2,自引:0,他引:2
Abstract. A no-tillage (NT) system was developed in semiarid Morocco to improve the soil fertility and stabilize yield through conservation of water. Results in two long-term trials (4 and 11 years) were able to show the effects of a no-tillage system in increasing total soil organic matter and total nitrogen. Over time, the quality of the NT soil surface was improved compared with that under conventional tillage (CT) with disc harrows. This effect was the result of an increase in soil organic carbon (SOC) and a slight decline in pH. However, over time, nitrogen decreased in both tillage practices, especially in the 0–25 mm layer (from 0.59 to 0.57 t ha−1 and from 0.44 to 0.42 t ha−1 under NT and CT, respectively). After 4 years of NT an extra 5.62 t ha−1 of SOC was sequestered in the 0–25 mm layer, and after 11 years the SOC increased further to 7.21 t ha−1 . 相似文献
43.
Briache Fatima Zahra Ennami Mounia Mbasani-Mansi Joseph Gaboun Fatima Abdelwahd Rabha Fatemi Zain El Abidine El-Rodeny Walid Amri Moez Triqui Zine El Abidine Mentag Rachid 《植物病害和植物保护杂志》2019,126(3):211-224
Journal of Plant Diseases and Protection - The parasitic weed Orobanche crenata is a serious constraint to legumes crops in Mediterranean area. In Morocco, heavy O. crenata infestation level was... 相似文献
44.
Journal of Plant Diseases and Protection - Prickly pear, Opuntia ficus-indica (L.) Miller (Caryophyllales: Cactaceae), cultivations in Morocco have been aggressively infested in recent years by the... 相似文献
45.
Petit R Aguinagalde I de Beaulieu JL Bittkau C Brewer S Cheddadi R Ennos R Fineschi S Grivet D Lascoux M Mohanty A Müller-Starck G Demesure-Musch B Palmé A Martín JP Rendell S Vendramin GG 《Science (New York, N.Y.)》2003,300(5625):1563-1565
Glacial refuge areas are expected to harbor a large fraction of the intraspecific biodiversity of the temperate biota. To test this hypothesis, we studied chloroplast DNA variation in 22 widespread European trees and shrubs sampled in the same forests. Most species had genetically divergent populations in Mediterranean regions, especially those with low seed dispersal abilities. However, the genetically most diverse populations were not located in the south but at intermediate latitudes, a likely consequence of the admixture of divergent lineages colonizing the continent from separate refugia. 相似文献
46.
Nabila Belhaj Frédéric Desor Céline Gleizes Frédéric M. Denis Elmira Arab-Tehrany Rachid Soulimani Michel Linder 《Marine drugs》2013,11(11):4294-4317
A phospholipopeptidic complex obtained by the enzymatic hydrolysis of salmon heads in green conditions; exert anxiolytic-like effects in a time and dose-dependent manner, with no affection of locomotor activity. This study focused on the physico-chemical properties of the lipidic and peptidic fractions from this natural product. The characterization of mineral composition, amino acid and fatty acids was carried out. Stability of nanoemulsions allowed us to realize a behavioral study conducted with four different tests on 80 mice. This work highlighted the dose dependent effects of the natural complex and its various fractions over a period of 14 days compared to a conventional anxiolytic. The intracellular redox status of neural cells was evaluated in order to determine the free radicals scavenging potential of these products in the central nervous system (CNS), after mice sacrifice. The complex peptidic fraction showed a strong scavenging property and similar results were found for the complex as well as its lipidic fraction. For the first time, the results of this study showed the anxiolytic-like and neuroprotective properties of a phospholipopeptidic complex extracted from salmon head. The applications on anxiety disorders might be relevant, depending on the doses, the fraction used and the chronicity of the supplementation. 相似文献
47.
Apollin Kuate Fotso Rachid Hanna Peter Kulakow Elisabeth Parkes Peter Iluebbey Francis Ajebesone Ngome Christopher Suh Jacques Massussi Ibrahim Choutnji Venasius Lendzemo Wirnkar 《Euphytica》2018,214(9):155
Genotype by environment interaction remains a substantial issue in all breeding programs. Crop genotypes are generally developed in a central breeding location, but always require the evaluation of breeding products in different environments. This is particularly relevant in countries that have a wide range of climates. Eighteen cassava genotypes were evaluated in Cameroon in eight environments—varying in seasonal rainfall and temperature patterns and soil characteristics—over two cropping seasons. Soil nutrient content was analyzed and trials were established in a randomized complete block design in three replications. Response of genotypes to major cassava pests and diseases, yield and carotenoids content was evaluated. It was observed that four genotypes did not show cassava mosaic disease (CMD) symptoms irrespective of the environments. The local check had highest CMD incidence and severity across all environments. Average number of whitefly per plant across all environments was highest on TMS 96/0023. Average cassava green mite (CGM) infestation was low on all the genotypes. Fresh root yield of five genotypes ranged between 25 and 30 tons per ha for both years. Significant and positive correlation was found across locations between fresh root yield and soil K, P and Mg. AMMI analysis revealed highly significant differences among genotypes and environments and significant genotype?×?environment interaction for most of the estimated traits, indicating variability in genotypes performance with environment. 相似文献
48.
A study of the molluscicidal and larvicidal activities of Citrullus colocynthis (L.) leaf extract and its main cucurbitacins against the mollusc Galba truncatula,intermediate host of Fasciola hepatica
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49.
R. Mrabet K. Ibno‐Namr F. Bessam N. Saber 《Land Degradation \u0026amp; Development》2001,12(6):505-517
A long‐term experiment comparing no‐till with conventional tillage systems across five rotations was evaluated 11 years after initiation. The objectives of the present paper are (1) to report differences in soil chemical properties (namely soil organic matter, total nitrogen, phosphorus, potassium and pH) that have resulted by converting from conventional to no‐till under contrasting cropping systems and (2) to draw tentative conclusions and recommendations on fertility status and fertilizer use and management. Soil in the no‐till system had increased surface soil organic C levels relative to conventional tillage regardless of rotation. In addition, depending on the rotation, the N and P content of the soil improved with no‐till compared with conventional tillage. In other words, no‐till has helped to retain soil organic matter (SOM), conserved more N, and resulted in increased extractable P and exchangeable K concentrations in the upper root‐zone. Hence, wheat produced in a no‐till system may receive more nutrients from decomposition of SOM and acidification of the seed zone. It is possible that lesser amounts of fertilizer nutrients will be needed because of the greater efficiency of nutrient cycling in no‐till systems relative to conventional systems. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献
50.
Environmental effects on the spatio‐temporal patterns of abundance and distribution of Sardina pilchardus and sardinella off the Mauritanian coast (North‐West Africa)
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Mahmoud Bacha Mohamed Ahmed Jeyid Vincent Vantrepotte David Dessailly Rachid Amara 《Fisheries Oceanography》2017,26(3):282-298
From 1998 to 2011, the effects of environmental conditions on the spatial and temporal trends of sardine and sardinella catch rates in the Mauritanian waters were investigated using generalized additive models. Two models were used: a global model and an oceanographic model. The global models explained more of the variability in catch rates (60.4% for sardine and 40% for sardinella) than the oceanographic models (42% for sardine and 32.4% for sardinella). Both species showed clear and inverse seasonal variations in abundances corresponding to their main spawning activities and the hydrologic seasons off the Mauritanian waters. Sardine prefer colder waters and seem to occupy the ‘gap’ in the northern part of the Mauritanian waters as soon as sardinella has left the area because of to lower water temperatures. Unlike sardinella, sardine showed a gradual southward extension between 2002 and 2009. The oceanographic model revealed that a high proportion of catch variability for the two species could be explained by environmental variables. The main environmental parameters explaining the variability are sea surface temperature (SST) and the upwelling index for sardinella, and the chlorophyll‐a (Chl‐a) concentration, the upwelling index and SST for sardine. The sardinella spatio‐temporal variations off Mauritania seem to be more controlled by thermal than productivity gradients, probably linked to the species physiological constraints (thermal tolerance) whereas sardine seems to be more controlled by an ‘optimal upwelling and temperature’ windows. The results presented herein may be useful for understanding the movement of these species along the Mauritanian coast and hence their management under a changing climate. 相似文献