1,721,101 research outputs found
Évaluation de la performance de triathlètes avant et après un apport exogène d'acides aminés ramifiés (BCAA)
No full textSchiraldi C., De Palo C., Gatti R., Spinella P. Évaluation de la performance de triathlètes avant et après un apport exogène d'acides aminés ramifiés (BCAA). In: Les Cahiers de l'INSEP, n°20, 1997. Un sport, deux enchaînements, trois disciplines : le triathlon. Actes du 1er symposium international de l'entraînement en triathlon. pp. 155-157
Biotechnological advances in the synthesis of modified chondroitin towards novel biomedical applications
No full textChondroitin sulfate (CS) is a well-known glycosaminoglycan present in a large variety of animal tissues, with an outstanding structural heterogeneity mainly related to molecular weight and sulfation pattern. Recently, few microorganisms, eventually engineered, proved able to synthesize the CS biopolymer backbone, composed of D- glucuronic acid and N-acetyl-D-galactosamine linked through alternating & beta;-(1-3)-and & beta;-(1-4)-glycosidic bonds, and secrete the biopolymers generally unsulfated and possibly decorated with other carbohydrates/molecules. Enzyme catalyzed/assisted methods and chemical tailored protocols allowed to obtain a variety of macromol-ecules not only resembling the natural extractive ones, but even enlarging the access to unnatural structural features. These macromolecules have been investigated for their bioactivity in vitro and in vivo establishing their potentialities in an array of novel applications in the biomedical field. This review aims to present an overview of the advancements in: i) the metabolic engineering strategies and the biotechnological processes towards chon-droitin manufacturing; ii) the chemical approaches applied to obtain specific structural features and targeted decoration of the chondroitin backbone; iii) the biochemical and biological properties of the diverse biotechnological-sourced chondroitin polysaccharides reported so far, unraveling novel fields of applications
Production of glucuronic acid based polysaccharides for biomedical applications by microbial fermentations.
No full textBeta-defensin-2 and -3 reduce intestinal damage caused by salmonella typhimurium infection.
No full textHigh-performance capillary electrophoresis to determine intact keratan sulfate and hyaluronic acid in animal origin chondroitin sulfate samples and food supplements
No full textChondroitin sulfate is extracted from animal cartilaginous tissues and is commercialized as active principle against osteoarthritis. Its biological activity depends on its purity grade and could be altered by the presence of other glycosaminoglycans like keratan sulfate that could be contemporarily extracted from animal tissues or like hyaluronic acid that, instead, is added on purpose in food supplements. Although numerous methods are reported in literature for quality control analyses of chondroitin sulfate, few of them are able to detect other glycosaminoglycans. In this paper, for the first time, a new high-performance CE method was set up to quantify the chondroitin sulfate, the eventual keratan sulfate, and hyaluronic acid as intact chains: five chondroitin sulfate standards and 13 animal origin samples or food supplements from six different suppliers were analyzed. The new method was able to determine keratan sulfate similarly to a previously reported high-performance anion-exchange chromatography method, but in addition it showed the advantage to determine also the hyaluronic acid as never reported before
Microbioreactor (micro-Matrix) potential in aerobic and anaerobic conditions with different industrially relevant microbial strains
Full text linkMicroscale fermentation systems are important high throughput tools in clone selection, and bioprocess set up and optimization, since they provide several parallel experiments in controlled conditions of pH, temperature, agitation, and gas flow rate. In this work we evaluated the performance of biotechnologically relevant strains with different respiratory requirements in the micro-Matrix microbioreactor. In particular Escherichia coli K4 requires well aerated fermentation conditions to improve its native production of chondroitin-like capsular polysaccharide, a biomedically attractive polymer. Results from batch and fed-batch experiments demonstrated high reproducibility with those obtained on 2 L reactors, although highlighting a pronounced volume loss for longer-term experiments. Basfia succiniciproducens and Actinobacillus succinogenes need CO2 addition for the production of succinic acid, a building block with several industrial applications. Different CO2 supply modes were tested for the two strains in 24 h batch experiments and results well compared with those obtained on lab-scale bioreactors. Overall, it was demonstrated that the micro-Matrix is a useful scale-down tool that is suitable for growing metabolically different strains in simple batch process, however, a series of issues should still be addressed in order to fully exploit its potential
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