**Abstract**

The message that everyone needs to know is that secondary metabolites in plants and natural products are involved in various activities. The phenolics, quinones, terpenes, flavonoids, and other thousands of low molecular weight metabolites activity is unknown. Well-understood secondary metabolites have been implicated in the defense against pathogens; the operating system of some of these has been established. In particular, to date, a relatively small number of processes have been shown to be targets of plant metabolism, including electron transport chains, mitochondrial function, and membrane integration. However, it is now emerging that other specific enzymes and processes may also be targets of specific metabolites. There is a general belief that modern genetic approaches will identify new targets and mechanisms of plant metabolism. Molecules that trigger apoptosis or autoimmunity in tumor cells, especially triterpenoids, are of particular interest in this regard. Before proceeding to specific studies in plant or human cells, we discuss whether there is a case for conducting preliminary studies on the mechanism of action in the genetic pathway system, such as yeast *Saccharomyces cerevisiae*, considering the approaches taken so far in botany and strategies that have led to success in the biomedical field.

**Keywords:** natural products, *Saccharomyces cerevisiae*, Defensins, pathogen
