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81.
82.
Microgreens are rich functional crops with valuable nutritional elements that have health benefits when used as food supplements. Growth characterization, nutritional composition profile of 21 varieties representing five species of the Brassica genus as microgreens were assessed under light-emitting diodes (LEDs) conditions. Microgreens were grown under four different LEDs ratios (%); red:blue 80:20 and 20:80 (R80:B20 and R20:B80), or red:green:blue 70:10:20 and 20:10:70 (R70:G10:B20 and R20:G10:B70). Results indicated that supplemental lighting with green LEDs (R70:G10:B20) enhanced vegetative growth and morphology, while blue LEDs (R20:B80) increased the mineral and vitamin contents. Interestingly, by linking the nutritional content with the growth yield to define the optimal LEDs setup, we found that the best lighting to promote the microgreen growth was the green LEDs combination (R70:G10:B20). Remarkably, under the green LEDs combination (R70:G10:B20) conditions, the microgreens of Kohlrabi purple, Cabbage red, Broccoli, Kale Tucsan, Komatsuna red, Tatsoi and Cabbage green, which can benefit human health in conditions with limited food, had the highest growth and nutritional content.  相似文献   
83.
Resumé Les auteurs ont étudié la composition chimique (N, substances humiques, lignine) de copeaux de bois blanc exposés à l'air libre depuis 2 à 10 ans, ainsi que leur type de peuplement fongique. En l'absence de lignivore, le pH, les taux de lignine et d'N s'élèvent et il se forme des quantités modérées d'humus à forte capacité d'échange. Dans le cas contraire, on voit apparaître, en abondance, des substances humiques peu condensées et la matière organique subit une évolution rappelant celle du mor.Avec la collaboration technique de Melle. M. Clet.Kononova, dans sa monographie5, signale de Troussov (1916) une étude que nous n'avons pas eu en mains.  相似文献   
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Chronic obstructive pulmonary disease (COPD) is a multifactorial chronic respiratory disease, characterized by an obstructive pattern. Understanding the genetic predisposition of COPD is essential to develop personalized treatment regimens. MicroRNAs (miRNAs) are small, endogenous, non-coding RNAs that modulate the expression levels of specific proteins based on sequence complementarity with their target mRNA molecules. Emerging evidences demonstrated the potential use of miRNAs as a disease biomarker. This pilot study aimed to investigate the association of the MIR-196a2 rs11614913 (C/T) polymorphism with COPD susceptibility, the clinical outcome and bronchodilator response to short-acting β2-agonist. Genotyping of rs11614913 polymorphism was determined in 108 COPD male patients and 116 unrelated controls using real-time polymerase chain reaction technology. In silico target prediction and network core analysis were performed. COPD patients did not show significant differences in the genotype distribution (p = 0.415) and allele frequencies (p = 0.306) of the studied miRNA when compared with controls. There were also no associations with GOLD stage, dyspnea grade, disease exacerbations, COPD assessment test for estimating impact on health status score, or the frequency of intensive care unit admission. However, COPD patients with CC genotype corresponded to the smallest bronchodilator response after Salbutamol inhalation, the heterozygotes (CT) had an intermediate response, while those with the TT genotype showed the highest response (p < 0.001). In conclusion MIR-196a2 rs11614913 polymorphism is associated with the bronchodilator response of COPD in our sample of the Egyptian population, generating hypothesis of the potential use of MIR-196a2 variant as a pharmacogenetic marker for COPD.  相似文献   
86.
Lipid production is an important indicator for evaluating microalgal species for biodiesel production. In this study, a new green microalga was isolated from a salt lake in Egypt and identified as Asteromonas gracilis. The main parameters such as biomass productivity, lipid content, and lipid productivity were evaluated in A. gracilis, cultivated in nutrient-starved (nitrogen, phosphorous), and salinity stress as a one-factor-at-a-time method. These parameters in general did not vary significantly from the standard nutrient growth media when these factors were utilized separately. Hence, response surface methodology (RSM) was assessed to study the combinatorial effect of different concentrations of the abovementioned factor conditions and to maximize the biomass productivity, lipid content, and lipid productivity of A. gracilis by determining optimal concentrations. RSM optimized media, including 1.36 M NaCl, 1 g/L nitrogen, and 0.0 g/L phosphorus recorded maximum biomass productivity, lipid content, and lipid productivity (40.6 mg/L/day, 39.3%, and 15.9 mg/L/day, respectively) which agreed well with the predicted values (40.1 mg/L/day, 43.6%, and 14.6 mg/L/day, respectively). Fatty acid profile of A. gracilis was composed of C16:0, C16:1, C18:0, C18:3, C18:2, C18:1, and C20:5, and the properties of fuel were also in agreement with international standards. These results suggest that A. gracilis is a promising feedstock for biodiesel production.  相似文献   
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In this study, citric acid was applied as a safe organic acid for the treatment of the brown macroalga Sargassum latifolium to facilitate the sequential extraction of fucoidan and alginate without cross contamination. Box-Behnken experimental design was used to investigate the effects of citric acid concentration, temperature, and time on fucoidan yield, its fucose and sulfate contents, and molecular weight (MW), while the investigated responses of the sequentially extracted alginate were yield, mannuronic/guluronic acid ratio (M/G) and MW. Under the optimized conditions, the fucoidan yield, fucose content, sulfate content, and MW were 6.55%, 21.01%, 30.92% and 7.12 × 103 Da, respectively, while alginate yield, M/G, and MW were 28.81%, 0.36, and 1.50 × 105 Da, respectively. The optimized products showed good Fe(III) chelating properties and the iron contents were 509.82 mg g?1 for fucoidan-Fe and 406.71 ± 5.18 mg g?1 for alginate-Fe. Under simulated gastrointestinal conditions, fucoidan-Fe and alginate-Fe complexes released 46 and 57% iron, respectively, which are nutritionally relevant amounts. Both fucoidan and alginate showed potent antioxidant properties, but their Fe complexes exhibited a reduced activity. The results of the present study indicated that citric acid could support the basis for an economical biorefinery process for the sequential extraction of fucoidan and alginate. Additionally, these polysaccharides could be good candidates for the preparations of iron supplements.

  相似文献   
89.
Russian Journal of Bioorganic Chemistry - In this study, a new class of furochromone derivatives bearing β-naphthol was synthesized via one-pot multicomponent reactions. First, condensation...  相似文献   
90.
Most natural populations of Drosophila melanogaster are polymorphic for two major electrophoretic variants at the esterase-6 locus. The frequency of the EST 6F allozyme is greatest in populations in warmer latitudes, whereas the EST 6S allozyme is predominant in colder latitudes. Latitudinal clines in electromorph frequencies are found on three continents. Purified preparations of the allozymes have been characterized for their pH optimum, substrate specificity, organophosphate inhibition, alcohol activation, thermal stability, and kinetic parameters. These and previous analyses of the EST 6 allozymes reveal that the two variants have differences in their physical and kinetic properties that may provide a basis for the selective maintenance of the polymorphisms and an explanation of the clinal variation observed in natural populations.   相似文献   
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