✍ Scribed by J. Carlos Roseiro; Alexandra C. Conceição; M.T. Amaral-Collaço
No coin nor oath required. For personal study only.
A 10000 Da hollow-fiber membrane characterized by an average hydraulic resistance of 9.5 x 106 Pa s m-i and an average transmembrane pressure of 1"5 x 106 Pa was used to concentrate a commercial fungal cellulase solution. The level of enzymatic activity increased slowly for the first 3 h before it started rising steeply in an exponential concentration effect due to solute polarization at the inner layer of the membrane, producing a flow rate decrease of approximately 20%.
Enzymatic activity yield and permeate flow were studied in a range between 940 and 1300 ml rain-i for cross-flow rate, 0.68 x 106 and 1"22 x 106 Pa for outlet pressure, and ultrafiltration time varying between 90 and 300 min. Pressure was revealed to be more important than cross-flow rate in the efficiency of the concentration. Also, a long lasting operation produced better results in terms of the studied responses than any combination of the other factors. The values of the specific activity of the cellulase components for an 8-h ultrafiltration period remained constant, indicating that no shear inactivation occurred.
📜 SIMILAR VOLUMES
After removal of ions, Xanthomonas campestris polysaccharides (xanthan) could be dissolved in distilled water to give the unordered conformation. In this condition, the polymers were susceptible to random degradation by fungal cellulases at 40-50". The products, including D-glUCOSe, oligosaccharide