Effect of the ionic liquid [bmim]Cl and high pressure on the activity of cellulase

The effect of the ionic liquid 1-butyl-3-methylimidazolium chloride ([bmim]Cl) and of high pressure on the activity of cellulase from Aspergillus niger were studied separately and in combination. The enzyme activity decreased with increasing concentrations of [bmim]Cl, reaching 50% the value in aqueous buffer with 20% [bmim]Cl. However, when the enzyme is held in 10% [bmim]Cl and is then assayed in 1% [bmim]Cl, it showed only 8% reduction of activity. These results can be explained by the fact that the activity of the enzyme in [bmim]Cl is linearly correlated with the decrease of the thermodynamic water activity (aw). Under pressure the enzyme activity varied from less 60% (at 200MPa) to equal (at 400 MPa), compared to atmospheric pressure. In 10% [bmim]Cl under pressure, cellulase activity is improved compared to atmospheric pressure, varying from equal (at 600 MPa) to 1.7-fold higher (at 100 MPa). This opens the possibility to improve cellulase activity in ionic liquids, and possibly of other enzymes, by carrying out the reaction under pressure

Swelling and dissolution of cellulose, Part III: plant fibres in aqueous systems

International audienceRaw and refined flax, hemp, abaca, sisal, jute and ramie fibres are dipped into N-methylmorpholine N-oxide (NMMO)-water with various contents of water and into hydroxide sodium (NaOH)-water. The swelling and dissolution mechanisms of these plant fibres are similar to those observed for cotton and wood fibres. Disintegration into rod-like fragments, ballooning followed or not by dissolution and homogeneous swelling are all observed as for wood and cotton fibres, depending on the quality of the solvent. Balloons are not typical of wood and cotton and they seem to be present in all plant fibres. Another interesting result is that the helical feature seen on the balloon membrane is not related to the microfibrillar angle. Plant fibres are easier to dissolve than wood and cotton. This is not related to the molar mass of the cellulose chain. Raw plant fibres keeping most its non-cellulosic components do not show the formation of balloons

Audit interne de la délivrance nominative des médicaments expérimentaux

CONTEXTE La dispensation nominative des médicaments expérimentaux est une mission quotidienne du pharmacien hospitalier. Elle doit respecter les référentiels réglementaires en vigueur en garantissant la sécurité des patients, la confidentialité et la traçabilité. OBJECTIFS Un audit a été mis en oeuvre afin d'évaluer la conformité et la qualité de la traçabilité de la dispensation nominative des médicaments expérimentaux, en regard des procédures internes existantes, dans le dynamisme du management de la qualité initiée sur le secteur d'activité. MATERIEL ET METHODES Une grille d'audit a été construite autour de 5 points à contrôler pour chaque dispensation : confidentialité, vérification pharmaceutique des mentions obligatoires de l'ordonnance, recherche du dossier de l'étude, délivrance et gestion des retours des traitements. L'audit s'est déroulé sur 2 semaines. La méthode de recueil utilisée a été l'observation directe par une stagiaire externe à l'équipe des essais cliniques