Searching for plant-derived natural products by in vitro cultivation

Modern cancer therapy uses more and more natural plant compounds for the development of new therapeutics during the last years. Some of them are rather approachable by the use of bioreactor and/or cell culture techniques than by green house cultivation or wild collection. More than 200 different species of herbs and rare medicinal plants with traditional use were taken into in vitro culture. In bioreactors with fully automated nutrient and gas exchange root, shoot and cell cultures were cultivated under different growth conditions. About 500 extracts were analysed by Analyticon's LC/MS-based Chemodiversity Profiling Platform. Combining bioreactor technology with high throughput screening methods high productive plants were selected according to their biomass production and content of active compounds. First results have been shown that in vitro cell and organ cultures can produce quantitatively more active compounds than plants of wild collection or green house culture. Compared to this, 20% of the bioreactor material showed a new chemical pattern of natural compounds. In addition, spectrum of secondary metabolites varies at different in vitro culture types. The most promising in vitro cultures were selected for scale-up in 5 to 10l bioreactors to optimise the production of preferable compounds. Fractionation of selected extracts and structure elucidation demonstrate that in vitro cultures are able to produce secondary metabolites with the same structural diversity as traditionally grown plants. Therefore, in vitro cultivated plants combined with the screening platform technology are an attractive source for identification of novel drugs and providing natural plant compounds as pharmaceutical products.