In last two decades there has been a great increase in research on medicinal plant.
A number of new medicines have been discovered and advancements in production
technology to harvest pharmaceutical important metabolites. During this period there
has also been an increase in research publication on medicinal plants. Figure 1
shows publication numbers for medicinal plant and traditional medicines in Africa.
Similar trends in medicinal plant research were also seen in the other parts of world
[29]. Due to successful research carried out during this period plant tissue culture is
an established field in plant cell biotechnology.