Investigation of Secondary Metabolite Production in Selected Australian Native Species via Plant Cell Suspension Culture

Abstract

Natural products and natural-product-derived substances comprised about 35% of the total pharmaceuticals market volume of US$230 billion in 1996 (Wessjohann, 2000). The success of natural-based drugs can be attributed to nature’s ability to induce effects by chemical means and many of these chemicals are able to pass species boundaries to cause an effect. Since plant secondary metabolites have evolved in the interaction with other organisms, many of them have interesting biological or therapeutical activities that are useful to man. In addition to their intriguing chemistry a number of these compounds are economically important, serving as pharmaceuticals, aromatics, fragrances, stimulants, colours and pesticides. Plant cell culture is viewed as a potential means of producing useful plant products without the inherent problems associated with conventional agriculture. Undifferentiated cell suspension cultures have the potential to produce varied secondary metabolites by the alteration of culture conditions or addition of chemicals to elicit expression of different metabolic pathways. Suitable substrate compounds may be biotransformed to a desired product using plant cell cultures. Biotransformation can produce compounds that can then be replicated by synthetic means or produce novel compounds that have previously not been identified or recognised as important. This thesis describes the initiation of plant suspension cultures for the purposes of examining the production of secondary metabolites of selected Australian native rainforest species.