Ultrafiltration Method To Remove Biosurfactant In Cephalosporin Fermentation Broth

Biosurfactants in the cephalosporin fermented liquid can be efficiently removed by ultrafiltration method, thereby eliminating the phenomenon of emulsification during the extraction experiments. In this paper, the cephalosporin fermented has been divided liquid into a different molecular weight range through the series and parallel two methods, using ultrafiltration separation technology. The most appropriate industrial production specifications of the ultrafiltration membrane have been screened by solvent extraction experiments. Meanwhile the composition of the sample fluid has been successfully identified by studying its scope of the surface. This paper has also carried on the preliminary study on membrane cleaning schemes, determining the optimal cleaning method and temperature.The main results were displayed as follow:Experiment established a more reasonable, fast, effective titer determination method and fermented total ? calculation method of the fermented liquid. This method is not only applicable to cephalosporin fermentation liquor, also applied to other antibiotics' industrial production.Experiment took series and parallel ultrafiltration technology to ultrafiltration partition of cephalosporin fermented liquid. 4 and 10 kD MWCO ultrafiltration membrane can effectively remove the biological macromolecules with emulsifying role in cephalosporin fermentation, avoiding the emulsifying phenomenon. 10 kD MWCO ultrafiltration membrane have finally been used in this study.More than 10 kD biological macromolecular material has a good surface activity, accounting for 83.41% of the solute mass. Among them, the protein component accounted for 17.52% of the total quality, within the range of 50-100 k D molecular weight range of about 31%; Polysaccharide accounted for 82.41% of the total quality, within the range of 50-100 kD molecular weight range of about 48%, greater than 140 kD molecular weight of above 37%.Especially above 140 k D biological macromolecular material, can make the surface tension of the water dropped to 34 mN/m. Molecular weight range for the best surface activity: > 140 kD, 100 kD- 140 kD, 50-140, the CMC values of which were 0.05%, 0.06% and 0.07% respectively. The biosurfactants in cephalosporin fermented liquid were polysaccharide and protein complex compounds(glycoprotein), molecular weight of about 60-70 kD.The formation of membrane fouling were mainly concentrated in the initial phase separation during the ultrafiltration separation process, it would be no longer increased after this stage. Within a certain range, the water flux of the ultrafiltration membrane increasesed rapidly with the increase of operating pressure. Experimental selected operating pressure 0.2 MPa, the best cleaning solution is: at 35 ?, positive and negative pressure cleaning with pure water, pure water reverse negative pressure cleaning, 0.4% NaOH solution cleaning, and then washed with pure water until neutral.In general, this study reasonable solved the emulsification problem in the process of cephalosporin separation, and the composition of biosurfactant in the fermented liquid was identified, provided experimental basis for industrial production of cephalosporin and Biosurfactants.