Search

Copyright of Revista CIATEC-UPF is the property of Revista CIATEC-UPF and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The main purpose of this work was the preliminary qualitative study of organic compounds in wastewaters of swine slaughterhouses. The samples were collected in a local abattoir and submitted to Liquid-Liquid Extraction (LLE) and Solid-phase Extraction (SPE) with XAD-4TM resin as stationary phase. The instrumental analysis was performed by Gas Chromatography with Mass Spectrometer Detector (GC/MSD). The compounds present in the LLE and SPE extracts were identified by the GC/MSD library (Wiley). The results pointed out that SPE and LLE can extract practically the same classes of compounds at the same amounts. LLE works well for the extraction of polar organic compounds, with acidified samples, while SPE presents a better performance for the extraction of less polar organic compounds. Aldehydes were main class of the compounds extracted by SPE and LLE and decenal was the major aldehyde identified. Fatty alcohols and carboxylic acids were also identified but in minor proportions. [ABSTRACT FROM AUTHOR]

The objective of this work was to evaluate the stability of the activity of commercial inulinase from Aspergillus niger immobilized in polyurethane foam. The activity of the enzyme was measured in the hydrolysis reaction of both sucrose and inulin at 50°C and pH 5.5. The enzyme reuse was evaluated during 59 days and 29 reuse cycles. The inulinase immobilized in polyurethane kept 49.7% and 49.4% of its initial activity during 1008 hand 24 reuse cycles for sucrose and inulin, respectively. In this work, enzyme immobilization was accomplished together with the formation of the polyurethane foam, which is an interesting characteristic, differing from several works found in the literature. Taking into account the promising results obtained, the low cost of the immobilization support employed and the whole technique developed, this work may comprise an innovative contribution. [ABSTRACT FROM AUTHOR]