Transgenic crops for improved pharmaceutical products

Transgenic plants have been obtained from a number of plant species, but only from a few medicinal plants. There are even fewer examples of studies on secondary metabolite production in transgenic medicinal plants. Because analyses have been performed on only a few plants far-reaching generalizations cannot be made. The secondary metabolite pathways are complicated, requiring several enzymatic steps to the desired end products used as pharmaceuticals. Thus, it is very difficult to regulate the production of secondary metabolites at the gene level. However, transgenic organ cultures, e.g, hairy roots and shooty teratomas with enhanced production capacity, have been obtained from several plant species via Agrobacterium transformation. In this review the possibilities and problems of producing pharmaceuticals by plant biotechnology are discussed. Comparison is made between whole plants and cell cultures, as well as conventional versus transgenic plants anti in vitro cultures.