PLANT HAIRY ROOT CULTURE: A PROMISING SYSTEM TO PRODUCE SECONDARY METABOLITE

Many plant secondary metabolites of interest are accumulated in roots. Harvesting roots is destructive for the plants and hence there has been increasing interest in developing hairy root cultures from several medicinal plant species. Hairy roots can be produced by transformation with the soil bacterium Agrobacterium rhizogenes, resulting in the so-called hairy roots disease. Hairy roots are induced when a plant is infected by an A.rhizogenes, by a part of a root inducing (Ri) plasmid in bacteria,called transfer DNA (T-DNA), which is transferred into the plant cell and expressed therein. The interest in hairy roots is mainly due to their ability to grow fast without needing an external supply of auxins. Many times, they do not need incubation under light. They are fairly well stable in metabolite yield due to their genetic stability.Several hairy roots have been put to scale-up studies in bioreactors. The use of bioreactor in micropropagation revealed its commercial applicability, and recently gained attention to commercial microprapagation process and also to produced valuable metabolite from plant. So, the hairy root cultures in bioreactor have opportunity to developing in the future, because many experiments on hairy root culture that produce valuable secondary metabolite have already established.