Production of Industrial Compounds
Cultured plant cells retain their metabolic potential and synthesise secondary products of commerce. Cell cultures can also be used as factories for bioconversion of intermediate compounds into more valuable products. Shikonin, an expensive compound, obtained from the roots of Lithospermum erythrorhizon, has been used by the Japanese traditionally as a vegetable dye and in cosmetics and toiletries. However, due to over exploitation this plant has become almost extinct in Japan.
To reduce dependence on import of this plant material, the Japanese scientists have developed a tissue culture method for the commercial production of Shikonin. Another example in which tissue culture production of an industrial compound has reached commercial level is Berberine from Coptis Japonica. In tissue cultures the yield of high value compounds can be enhanced by feeding the cells with precursors of their biosynthetic pathway (Biotransformation), manipulation of the culture conditions and selecting high yielding cell lines. The production of secondary plant products of commerce would considerably reduce the pressure on shrinking arable land. Besides its practical application, tissue culture systems have been found ideal to study basic aspects such as alternation of generation, morphogenesis, growth and differentiation and host-pathogen interaction. In fact, one important fundamental contribution of plant tissue culture is the discovery of cytokinins.