Plant cells : immobilization and oxygen transfer

摘要: The study described in this thesis is part of the integrated project 'Biotechnological production non-persistent bioinsecticides by means plant cells vitro ' and was done close cooperation with research Institute Ital within framework NOVAPLANT. used were Tagetes species which produce thiophenes, naturally occurring biocides, particularly against nematodes. objective to use immobilized or large cell aggregates for secondary metabolite production. In particular upscaling immobilization techniques cells, role diffusion limitation oxygen as a substrate on its effect subject research. A literature survey presented Chapter 2. advantages several aspects concerning techniques, consequences immobilization, reactors, future prospects are discussed Chapter. 3 deals application resonance nozzle an technique high capacity well yeast calcium alginate gel beads. It found that has two orders magnitude larger than conventional dripping needle. viability after preserved. An extension applicability thermogelling supports (k-carrageenan, agar gellan gum) Is 4. Plant bacterial insect model systems experiments. 5, occurrence Daucus carota agarose, (κ-carrageenan, determined respiration measurements order explain enhanced pronounced from reported However, our experiments no differences between support materials could be observed. effective coefficient (ID e ) material important factor mathematical calculations quantify limitation. 6 different (calcium alginate, κ-carrageenan, gum, agarose) measuring well- stirred solution into beads, initially free oxygen. fitted experimental data resulting value following parts calculation concentration profiles beads containing visualize 7 tested validity measurement agarose respiring minuta . This aid microelectrode tip 15 μm. calculated correspond quite well. 8 effects aggregate size thiophene growth patula concluded related observation 'optimum' where highest. Calculations showed due absence centre aggregates.