Precursors and elicitors on production of secondary metabolites.pptx

Secondary metabolites

1. Precursors and elicitors on production of secondary metabolites.

2. Elicitors Elicitors are molecules that stimulate plants to produce secondary metabolites, which are compounds not directly involved in growth but play roles in defense . These compounds can be biotic (from living sources) or abiotic (non-living). Elicitors trigger a cascade of signaling events that lead to increased synthesis and accumulation of secondary metabolites. Elicitors are substances which induce physiological changes in the plant cells. Plants cells respond to these stressors by activating an array of mechanisms, similar to the defense responses to pathogen infections or environmental factors. They affects the metabolism. Enhances the synthesis of phytochemical/plant secondary metabolites.

3. Utilization of elicitation of plant tissue cultures in various areas of research. Elicitors Plant Tissue Culture Investigation of Plant Defense Mechanisms Increase Yield of Target Substance Investigation of Enzymology of Secondary Metabolism Investigation of Regulation of Secondary Metabolism

4. Elicitation of  In vitro  products Plants and/or plant cells  in vitro  show physiological and morphological responses to microbial, physical, or chemical factors which are known as “elicitors. Elicitation is a process of inducing or enhancing synthesis of secondary metabolites by the plants to ensure their survival, persistence, and competitiveness. The study was applied in several abiotic elicitors to enhance growth and ginseng saponin biosynthesis in the hairy roots of  P. ginseng . Generally, elicitor treatments were found to inhibit the growth of the hairy roots, although simultaneously enhancing ginseng saponin biosynthesis. Tannic acid profoundly inhibited the hairy root growth during growth period.

5. Precursors in secondary metabolites. Precursors, which are building blocks for the synthesis of secondary metabolites, are derived from primary metabolites like amino acids, sugars, and fatty acids. These primary metabolites undergo modifications through secondary metabolic pathways to produce a wide range of secondary metabolites. 

6. Types of Precursors and Their Roles: Amino Acids: Aromatic amino acids like phenylalanine, tyrosine, and tryptophan are key precursors for the shikimate pathway, which leads to the production of various phenolic compounds and alkaloids. Acetyl-CoA: This molecule is a central precursor for the biosynthesis of polyketides and other secondary metabolites. Other Primary Metabolites: Sugars, fatty acids, and other organic acids can also be modified and used as precursors for secondary metabolism.

7. Examples of Secondary Metabolite Synthesis and Precursors: Alkaloids: Many alkaloids are synthesized from amino acids, with modifications like decarboxylation, cyclization, and the introduction of nitrogen-containing groups. Terpenoids: These compounds are derived from the isoprenoid units, which are formed from mevalonic acid. Phenolic Compounds: The shikimate pathway produces aromatic precursors like phenylpropanoids, which can be further modified to form flavonoids, coumarins, and other phenolic secondary metabolites.

8. Significance of Precursor Studies: Understanding the roles of precursors helps in unraveling the biosynthesis of secondary metabolites and can aid in developing strategies to enhance their production. By studying precursor supply, researchers can manipulate the biosynthetic pathway to produce novel variants of secondary metabolites. Precursor-directed biosynthesis, where precursors are intentionally added to the fermentation medium, can lead to higher yields and the production of specific compounds.