Smart immobilization of whole cell biocatalysts

Purpose and goal

The goal of the project was to test chitosan and temperature sensitive polymers to immobilize G.oxydans for the production of DHA. This was done according to plan and thus the goal was achieved. The purpose was to successfully demonstrate the novel immobilization method. This was only partly achieved, since results was not conclusive in the case of the DHA process and indicated that more research is required in order to showcase the advantages with the method

Results and expected effects

The results from the chitosan 3L scale experiments showed that the recycling was effective when using a short centrifugation step and that pH control was possible using the fermentor. Control reaction without chitosan gave expected results, but in the three following experiments with chitosan the activity was lower than expected.The reason was found later to be caused by a low amount of active G.oxydans (before adding the chitosan). The temperature sensitive polymer could effectively immobilize G.oxydans, but not in conditions similar to those in the end of a reaction.

Approach and implementation

The approach was to start with the chitosan experiments. These are time demanding and thus important to start with. Meanwhile the results were obtained from these experiments the production and testing of the temperature sensitive polymers were performed.