Poster: Secondary Metabolism

Abs # 295: Monitoring of Several Medicinally Important Secondary Metabolites Production Through In Vitro Cultivation

Presenter:	Kaufman, Peter B, pbk@umich.edu
Authors	Kaufman, Peter B (A) (B)  Kirakosyan, Ara  (A) (B)  Warber, Sara  (B)
Affiliations:	(A): MCDB Department, University Of Michigan (B): Complementary & Alternative Medicine Research Center

We have established different systems of cell cultures: callus, cell suspension and organ cultures of several medicinal important plants such as St John’s wort (Hypericum perforatum), kudzu wine (Pueraria montana), and hawthorn (Crataegus laevigata and C. monogina). Consequently, the contents of important secondary metabolites, dianthrones, phloroglucinol derivatives, isoflavonoids, flavonoids and proanthocyanidins at different stages of morphogenesis and regeneration were determined. These cell cultures are able to produce the desired compounds, however, in extremely varied amounts. Our investigations connected with multiple shoot regeneration showed that in shoots the content of several of these phytopharmaceuticals is higher than in intact plants. The yield of secondary metabolites from callus and cell suspension cultures is much lower than concentrations found in intact plants. Poor performance of cultures can be attributed, in part, to a lack of knowledge of the regulation of secondary metabolism and the lack of “production triggers” to manipulate metabolism. Since the discovery that factors that suppress growth often promote secondary metabolism, work in this field has identified culture conditions and additives that can shift cultures into higher productivity states. Also, we will be able to take advantage of the wide range of biosynthetic capacity within cultures, either by selection or by screening germplasm for highly productive cell lines. As a first step in teasing apart the contributions of genetic or environmental influences, in vitro cultures were used. Whether the specific levels of the phytochemicals in the studied populations are the result of environmental influences rather than genetic influences need further study.