No abstract

No abstract

The ground state, and elastic properties of copper halides in their zinc blende, NaCl and intermediate structures have been calculated using a two‐body potential of the Buckingham type coupled with a molecular dynamics simulation. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)

Bacteria are attracting the interest of worldwide investors; their use is interesting in several industrial fields, this organism produces a wide variety of extracellular enzymes, including proteases. The objective of this study was to evaluate the production of protease by different bacterial strains isolated from local marine samples collected from the Cap Rousseau beach in the Oran city, northwestern Algeria, 44 bacterial isolates were tested for protease production by cultivating them on skim milk agar medium. The proteolytic activities of all strains were tested using skim milk agar and gelatin agar. Among the 14 isolates that showed a significant hydrolysis diameter, two bacterial strains EC23 and EC2S3 demonstrated the highest potential for protease production and they were selected for further studies. In addition, the extracellular protease was examined using the fermentation production medium at 30°C for 48h, with a constant agitation of 150 rpm. The enzyme activity was determined under varying conditions of pH, incubation temperature, and salt concentration, using Sigma's Universal Protease Activity Assay. The enzyme from EC23 strain showed higher activity in all cases than the EC2S3 strain, which indicated that it was the most ideal organism for enzyme production.

The complexation process between benzo[a]pyrene (BaP) and γ-cyclodextrin (γ-CD) was computationally studied using DFT methodology. Several initial configurations of the interaction of BaP with γ-CD were explored to determine the most stable inclusion complex. According to the calculated complexation energies, the BaP/γ-CD complex is found to be the most favorable energetically when the BaP guest is totally entrapped into γ-CD cavity. The inclusion process involving the encapsulation of two guests BaP in the cavity of γ-CD is also thermodynamically favored. Van der Waals interactions play a determinant role in stabilizing BaP/γ-CD and 2BaP/γ-CD complexes.