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The present article describes two new applications of plastic-based cell culture systems in the plant biotechnology domain.
Different types of bioreactors are used at Nestlé R&D Center-Tours for large scale culture of plants cells to produce metabolites
or recombinant proteins and for mass propagation of selected plant varieties by somatic embryogenesis. Particularly, recent
studies are directed to cut down the production costs of these two processes by developing disposable cell culture systems.
For large scale culture, two novel flexible plastic-based disposable bioreactors have been developed from 10 to 100 l working
volumes, validated with several plant species (“Wave and Undertow” and “Slug Bubble” bioreactors). Vegetative propagation
of elite plant varieties is achieved through somatic embryogenesis in liquid medium. A pilot scale process has been recently
set up for the industrial propagation of Coffea canephora (Robusta coffee). The current production capacity is 2.5–3.0 million embryos per year. The pre-germination of the embryos
was previously conducted by temporary immersion in liquid medium in 10-l glass bioreactors. An improved process has been developed
using a 10-l disposable bioreactor consisting in a bag containing a rigid plastic box (“Box-in-Bag” bioreactor), insuring,
amongst other advantages, a higher light transmittance to the biomass due to its horizontal design. 相似文献
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Every biotechnology process that relies on the use of bacteria to make a product or to overproduce a molecule may, at some time, struggle with the presence of virulent phages. For example, phages are the primary cause of fermentation failure in the milk transformation industry. This review focuses on the recent scientific advances in the field of lactic acid bacteria phage research. Three specific topics, namely, the sources of contamination, the detection methods and the control procedures will be discussed. 相似文献
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Van Wormhoudt A Roussel V Courtois G Huchette S 《Marine biotechnology (New York, N.Y.)》2011,13(3):563-574
Two subspecies of the European abalone have been morphologically recognized: Haliotis tuberculata tuberculata, present in the North Atlantic, and Haliotis tuberculata coccinea, present in the Canary Islands. Among the different nuclear markers used to differentiate these two subspecies, the sperm
lysin gene was the most reliable, leading to a 2.2% divergence. Concerning the subunit I of the mitochondrial cytochrome oxydase
gene (COI), we observed a difference of 3.3% between the two subspecies. In the North Atlantic, an introgression of mitochondrial
DNA from H. tuberculata coccinea to H. tuberculata tuberculata was evident in around 30% of individuals. Due to this difference, we were able to experimentally detect the transfer of paternal
mitochondrial DNA (mtDNA) by specific quantitative polymerase chain reaction measurements. The presence of the two mtDNA signatures
was also detected in 20% of individuals tested in the field. Moreover, one mt DNA hybrid sequence was identified. The sequencing
of this mitochondrial DNA hybrid revealed a mosaic structure with many specific mutations. The origin of this hybrid sequence
is discussed. 相似文献
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Résumé Un marquage à l'or radio-actif de butineuses deFormica polyctena a été effectué le long d'une piste de butinage. Nous avons constaté que les échanges de nourriture étaient très faibles entre ouvrières travaillant sur des pistes différentes.
Ce travail est dédié au Pr. KonradLorenz, pour son soixantième anniversaire. 相似文献
Summary Labelling foraging ants (Formica polyctena) with radioactive gold on a foraging path, the authors observe that the exchange of food are very weak between foragers from differents paths.
Ce travail est dédié au Pr. KonradLorenz, pour son soixantième anniversaire. 相似文献
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Belma Giray Josiane Arnaud İskender Sayek Alain Favier Filiz Hıncal 《Journal of trace elements in medicine and biology》2010,24(2):106-110
Importance of iodine and selenium in thyroid metabolism is well known, but the roles of other essential trace elements including copper, zinc, manganese and iron on thyroid hormone homeostasis remain unclear. The aim of this study was to investigate the status of those trace elements in benign thyroid diseases and evaluate possible links between trace element concentrations and thyroid hormones.The study group was composed of 25 patients with multinodular goiter. Concentrations of thyroid hormones (plasma-free thyroxine, FT4; free triiodothyronine, FT3; and thyrotropin, TSH), selenium, copper, zinc, manganese and iron in plasma, and urinary iodine were determined. The results were compared with those of a healthy control group (n=20) with no thyroid disorder.A mild iodine deficiency was observed in the patients with multinodular goiter whereas urinary iodine levels were in the range of “normal” values in healthy controls. All patients were euthyroid, and their thyroid hormone concentrations were not significantly different from the control group. Plasma selenium, zinc and iron concentrations did not differ from controls, while copper and manganese levels were found to be significantly higher in the patients with multinodular goiter indicating links between these trace elements and thyroid function and possibly in development of goiter. Besides iodine, there was a significant correlation between plasma copper concentration and FT3/FT4 ratio. 相似文献
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