Plants secondary metabolites also known as phytochemicals
Metabolism is the sum of all chemical reactions that occur in the cells of living organisms to maintain life. The intermediates and products of metabolism are called metabolites. Plant metabolites fall into two categories, namely primary and secondary metabolites. Primary metabolites are compounds synthesized by plants directly associated with growth and development. These (carbohydrates, lipids, and proteins..) are common to all living organisms and paramount for their survival. On the other hand, secondary metabolites although often derived from primary metabolism are not vital for keeping the plant alive. Contrary to primary metabolites, their absences doesn’t immediatly impair plant life but surely decrease their ability to survive. They are often differentially distributed among limited taxonomic groups.
Role of secondary metabolites in the plant kingdom
They are important primarily in ecological interactions with the surrounding living organisms. Not only as defense compounds against parasites, pathogens and predators but also as attractant for pollinators and dispersing animals. Other secondary metabolites are involved in protection against environmental stress (e.g. excess sunlight, drought).
Benefits for human and animal health
Plants secondary metabolites have shown to possess various biological effects and are generally defined as the bioactive compounds of plants. In the pharmaceutical industry, they are used as antibiotics, enzyme inhibitors, immunomodulators, antitumor agents, anticancer…. Aside from direct medicinal applications, many phytochemicals also serve as chemical templates for the synthesis or semi-synthesis of new drugs.
Industrial applications
Plant secondary metabolites are high value chemicals with applications in a wide range of domains.
- In food industry : they are used as antioxidant, antimicrobial, pigment, flavoring agent, nutraceutical
- In feed industry : they are used as pigment, feed additive
- In agriculture : they are used as bioherbicide, bioinsecticide, biopesticide, plant growth regulator