ABSTRACT
<p><b>OBJECTIVE</b>To cultivate adventitious roots of Hypericum perforatum in bioreactors, in order to seek for suitable conditions for adventitious growth.</p><p><b>METHOD</b>The effect of IBA concentration, sugar type and concentration, inoculum volume and air volume of adventitious roots on the cultivation of adventitious roots of H. perforatum was observed in a 5 L air-lift bioreactor.</p><p><b>RESULT</b>Adventitious roots of H. perforatum were cultivated in a MS culture dish. With the increase of IBA concentration, the propagation coefficient of adventitious roots of H. perforatum was on the rise. The IBA concentration ranging between 1.25-1.75 mg x L(-1) was suitable for the growth of adventitious roots. Adventitious roots grew best with sucrose in MS medium, with the propagation coefficient up to 22.15. When sucrose concentration was 30 g x L(-1), fresh weight, dry weight and propagation coefficient reached the maximum value. An adventitious root reactor with an inoculum volume of 20 g was favorable for the growth of adventitious roots. The air volume of reactors of 0.075 vvm (air volume/culture volume per minute) was favorable for the growth of adventitious roots, with the significant increase in the propagation coefficient of adventitious roots. In the amplification experiment, we found that the cultivation conditions of adventitious roots in a 5 L bioreactor was completely applicable to that in 10 and 20 L bioreactors, and adventitious roots grew well in a large bioreactor.</p><p><b>CONCLUSION</b>IBA concentration, sugar type and concentration, inoculum volume and air volume had a significant effect on the growth of adventitious roots.</p>