The growth experiments in which plant cell suspensions of N. tabacum 1507 and L. vera MM were cultivated in two-phase systems were carried out in order to select the best phase formulation ensuring culture growth. The highest growth observed for N. tabacum 1507 occurred in 5% PEG 6000/10% dextran 70 000. The overproduction of extracell phenolic compounds from both cell cultures in the formulated two-phase systems was investigated. The best two-phase system ensuring higher production of phenolic compounds from both cell cultures is 4% PEG 20 000/7.5% dextran 70 000. The plant cell suspensions of N. tabacum 1507 produced 0.171 g dm−3total phenolic compounds in this system (against 0.028 g dm−3from control fermentation). In the same two-phase system, the plant cell suspension from L. vera MM produced 0.387 g dm−3total phenolic compounds (against 0.058 g dm−3from control fermentation). In both cases the phenolic partitioned mainly in the top phase.