An integrated ''root tube'' bioreactor/separator for transformed root cultures

The special morphology and biochemical characteristics of transformed hairy roots demand novel approaches in bioreactor concept to provide a favorable environment for root growth and product extraction. This paper describes our evaluation of the performance of an integrated bioreactor (1 l) and separation system. Growth rates of transformed Nicotiana glauca roots were comparable to those achieved in Erlenmeyer flasks, but the release of alkaloids was enhanced using production medium and heat treatment. Incorporation of an XAD-4 resin packed column separator also facilitated alkaloid release and improved recovery. In addition transformed roots of N. glauca, Nicotiana rustica and Datura stramonium were cultured in a 8 l bioreactor, achieving high growth rates and productivities comparable to reported values.