caa a22 4500 465822800 CHVBK 20180323112140.0 cr unu---uuuuu 170327e19901001xx s 000 0 eng 10.1007/BF00170917 doi (NATIONALLICENCE)springer-10.1007/BF00170917 A fed-batch technique for 2-heptanone production by spores of Penicillium roquefortii [Elektronische Daten] [Catherine Creuly, Christian Larroche, Jean-Bernard Gros] Summary: A fed-batch technique for the production of 2-heptanone from octanoic acid by Ca-alginate/Eudragit RL-entrapped spores of Penicillium roquefortii is presented. It involves the use of a pH-stat apparatus, the increase in pH arising due to the reaction being overcome by direct substrate addition. When the reaction is performed at pH 5.5, no true constant rate period can be achieved due to a gradual buffering of the medium connected with a decrease in the catalytic activity of the spores. At pH 6.5 the system exhibits high stability and the reaction rate remains constant for at least 300 h with a value of 0.975 mM/h and a substrate concentration close to 4 mM. The process used may be very useful in the study of long-term behaviour of biocatalysts when the medium is not renewed and when the reaction involves an ionic compound and a neutral one. Springer-Verlag, 1990 Creuly Catherine Laboratoire de Génie Chimique Biologique, Université Blaise Pascal, F-63177, Aubiere cedex, France aut Larroche Christian Laboratoire de Génie Chimique Biologique, Université Blaise Pascal, F-63177, Aubiere cedex, France aut Gros Jean-Bernard Laboratoire de Génie Chimique Biologique, Université Blaise Pascal, F-63177, Aubiere cedex, France aut Applied Microbiology and Biotechnology Springer-Verlag 34/1(1990-10-01), 20-25 0175-7598 34:1<20 1990 34 253 https://doi.org/10.1007/BF00170917 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/BF00170917 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Creuly Catherine Laboratoire de Génie Chimique Biologique, Université Blaise Pascal, F-63177, Aubiere cedex, France aut NATIONALLICENCE 700 1- Larroche Christian Laboratoire de Génie Chimique Biologique, Université Blaise Pascal, F-63177, Aubiere cedex, France aut NATIONALLICENCE 700 1- Gros Jean-Bernard Laboratoire de Génie Chimique Biologique, Université Blaise Pascal, F-63177, Aubiere cedex, France aut NATIONALLICENCE 773 0- Applied Microbiology and Biotechnology Springer-Verlag 34/1(1990-10-01), 20-25 0175-7598 34:1<20 1990 34 253 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer