caa a22 4500 465824668 CHVBK 20180323112145.0 cr unu---uuuuu 170327e19900801xx s 000 0 eng 10.1007/BF00172540 doi (NATIONALLICENCE)springer-10.1007/BF00172540 Immobilization of anaerobic thermophilic bacteria for the production of cell-free thermostable α-amylases and pullulanases [Elektronische Daten] [M. Klingeberg, K. Vorlop, G. Antrakinian] Summary: For the production of cell-free thermostable α-amylases and pullulanases various anaerobic thermophilic bacteria that belong to the genera Clostridium and Thermoanaerobacter were immobilized in calcium alginate gel beads. The entrapment of bacteria was performed in full as well as in hollow spheres. An optimal limited medium, which avoided bacterial outgrowth, was developed for the cultivation of immobilized organisms at 60° C using 0.4% starch as substrate. Compared to non-immobilized cells these techniques allowed a significant increase (up to 5.6-fold) in the specific activities of the extracellular enzymes formed. An increase in the productivity of extracellular enzymes was observed after immobilization of bacteria in full spheres. In the case of C. thermosaccharolyticum, for instance, the productivity was raised from 90 units (U)/ 1012 cells up to 700 U/1012 cells. Electrophoretic analysis of the secreted proteins showed that in all cases most of the amylolytic enzymes formed were released into the culture medium. Proteins that had a molecular mass of less than 450 000 daltons could easily diffuse through the gel matrix. Cultivation of immobilized bacteria in semi-continuous and fed-batch cultures was also accompanied by an elevation in the concentration of cell-free enzymes. Springer-Verlag, 1990 Klingeberg M. Institut für Mikrobiologie der Universität Göttingen, Grisebachstrasse 8, D-3400, Göttingen, Federal Republic of Germany aut Vorlop K. Institut für Technische Chemie der Technischen Universität Braunschweig, D-3300, Braunschweig, FRG aut Antrakinian G. Technische Universität Hamburg-Harburg, Arbeitsbereich Biotechnologie I, Technische Mikrobiologie, Harburger-Schlosstrasse 37-39, D-2100, Hamburg-Harburg, Federal Republic of Germany aut Applied Microbiology and Biotechnology Springer-Verlag 33/5(1990-08-01), 494-500 0175-7598 33:5<494 1990 33 253 https://doi.org/10.1007/BF00172540 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/BF00172540 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Klingeberg M. Institut für Mikrobiologie der Universität Göttingen, Grisebachstrasse 8, D-3400, Göttingen, Federal Republic of Germany aut NATIONALLICENCE 700 1- Vorlop K. Institut für Technische Chemie der Technischen Universität Braunschweig, D-3300, Braunschweig, FRG aut NATIONALLICENCE 700 1- Antrakinian G. Technische Universität Hamburg-Harburg, Arbeitsbereich Biotechnologie I, Technische Mikrobiologie, Harburger-Schlosstrasse 37-39, D-2100, Hamburg-Harburg, Federal Republic of Germany aut NATIONALLICENCE 773 0- Applied Microbiology and Biotechnology Springer-Verlag 33/5(1990-08-01), 494-500 0175-7598 33:5<494 1990 33 253 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer