IMMOBILIZATION OF PLANT-CELLS IN HYBRID SOL-GEL MATERIALS

Cells of three different plant species were immobilized on a glass fib er fabric by sol-gel deposition. The process involved the following st eps: (1) reinforcement of glass-fiber supports by coating with a gelli ng solution of hybrid-SiO2 precursors, (2) entrapment of-cells by stuf fing the voids of the support with a suspension cell culture, (3) achi evement of a definite immobilization by a primary treatment with SiO2- sol, followed by gas phase reaction of tetraethoxysilane and diethoxym ethylsilane with OH groups of cell wall and of surface silica. Immobil ized cells maintained their viability as tested by the positive reacti on to TTC and by the development of calli from stretched samples. The samples did not release cells in solution over a time period of four m onths, at least. The biosynthetic capability of one of immobilized spe cies, Coronilla vaginalis, was studied by periodically monitoring the production of umbelliferone and marmesin which constituted the major s econdary metabolites produced by in vitro cultured cells of this speci es. The results were evaluated in order to determine the versatility o f the method and its potential for exploitation in continuous industri al-scale production of rare and fine chemicals.