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Guillaume Delfau-Bonnet Nabila Imatoukene Tiphaine Clment Michel Lopez Florent Allais Anne-Lise Hantson 《Marine drugs》2022,20(4)
Projections show that the cultivation of microalgae will extend to the production of bio-based compounds, such as biofuels, cosmetics, and medicines. This will generate co-products or residues that will need to be valorized to reduce the environmental impact and the cost of the process. This study explored the ability of lipid-extracted Chlorella vulgaris residue as a sole carbon and nitrogen source for growing oleaginous yeasts without any pretreatment. Both wild-type Yarrowia lipolytica W29 and mutant JMY3501 (which was designed to accumulate more lipids without their remobilization or degradation) showed a similar growth rate of 0.28 h−1 at different pH levels (3.5, 5.5, and 7.5). However, the W29 cell growth had the best cell number on microalgal residue at a pH of 7.5, while three times fewer cells were produced at all pH levels when JMY3501 was grown on microalgal residue. The JMY3501 growth curves were similar at pH 3.5, 5.5, and 7.5, while the fatty-acid composition differed significantly, with an accumulation of α-linolenic acid on microalgal residue at a pH of 7.5. Our results demonstrate the potential valorization of Chlorella vulgaris residue for Yarrowia lipolytica growth and the positive effect of a pH of 7.5 on the fatty acid profile. 相似文献
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Analysis of amino acid uptake and translocation in Arabidopsis with a low‐cost hydroponic system
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In soils, amino acids may be an important source of nitrogen for plants, at least in those where organic matter is not quickly degraded. The physiology of uptake of amino acids by roots was mainly studied in the 70's and 80's, before genes encoding amino acid importers were cloned in the 90's. While two families of amino acid transporters have been identified, yielding a total of about 100 genes, the role of each member is yet to be elucidated. As a tool for studying the role of amino acid transporters from Arabidopsis we set up a new hydroponic system suitable for radioisotope use. This system enables reproducible amino acid uptake by roots and estimation of the transport to the shoots of the amino acid taken up. We show that the rates of glutamine (Gln) uptake by wild‐type roots and transfer to the shoots were linear, and that other tested amino acids were translocated to the shoots with lower efficiency than Gln. A T‐DNA insertion mutant for a Gln exporter was compared to the wild‐type plants. Gln uptake and transfer were similar in both genotypes, showing that the suppression of the exporter did not affect uptake or transfer of amino acids to the shoots. The main advantage of the hydroponic system presented here is that all the materials used to grow Arabidopsis are virtually free and can therefore be discarded, a useful feature when working with radioactivity. 相似文献
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Context
Sustained timber harvesting conflicts with the long-term viability of boreal caribou (Rangifer tarandus caribou) populations. The spatial arrangement of harvest blocks in the landscape could mitigate the impact of logging on caribou populations. For the forest industry, however, these measures represent constraints that reduce the annual allowable cut (AAC).Objective
Estimate the long-term impacts of spatial constraints to harvesting, applied alone or in combination, on AAC and boreal caribou populations.Methods
We divided a 30,000 km2 region into 20 harvest block sizes varying from 50 to 1000 km2, and modeled the implementation of spatially explicit harvest schedule plans in combination with wildfire and caribou population dynamics. We then evaluated the probability of persistence of boreal caribou populations.Results
The probability of maintaining an AAC target declined with increasing target AAC, increasing size of operating area, and increasing adjacency constraints. In contrast, the probability of maintaining caribou populations declined with increasing AAC, decreasing size of operating areas, and decreasing adjacency constraints. An increase in operating area size from 50 to 300 km2 produced a considerable gain in AAC for all adjacency constraints.Conclusions
Because adjacency constraints led only to a small increase in the probability of maintaining caribou populations, we recommend adopting less constraining landscape management actions, such as a 70-year period between two consecutive harvests in the same ~300-km2 operating area.7.
Mohammed Faez Guillaume Dom Abdulwali Nada Harhar Hicham Al-Jobory Hala J. 《Plant foods for human nutrition (Dordrecht, Netherlands)》2020,75(2):230-235
Plant Foods for Human Nutrition - Argan oil is prepared by cold pressing argan kernels collected from fully ripe fruit. Argan oil market price is particularly elevated. Consequently, efficient... 相似文献
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Albertine Léon Stéphane Pronost Jackie Tapprest Nathalie Foucher Béatrice Blanchard Geneviève André-Fontaine Claire Laugier Guillaume Fortier Roland Leclercq 《Journal of veterinary diagnostic investigation》2006,18(2):218-221
Studies were carried out to determine the cause of death in a prematurely born Thoroughbred foal that died 24 hours after birth. Necropsy revealed gross lesions suggestive of septicemia. A commercial Leptospira polymerase chain reaction (PCR) assay designed to specifically amplify the hemolysis-associated protein 1 (hap1) gene present only in pathogenic Leptospira strains detected the presence of Leptospira DNA in various tissues of the foal. Histologic examination of lung, liver, kidney, and myocardium revealed numerous spirochetes in Warthin-Starry-stained tissue sections. Results of PCR analysis and histologic examination suggested a leptospiral infection in the newborn foal. At the moment of death, the infection coexisted with a streptococcal-associated aspiration bronchopneumonia and postpartum septicemia. These findings indicate that the PCR assay based on the amplification of the hap1 gene represents a useful tool for specific detection of pathogenic leptospira in field samples taken from horses. 相似文献
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