developed by different biological and environmental conditions such as dehydration, chemical treatment, microbial infection, mechanical injury to the plants, and
UV irradiation. They are manufactured for pharmaceutical benefits, for example, as
oleoresins and gum, e.g., gossypol. Gossypol is useful for male antifertility activity
and insecticidal activity (Kaur 2010).
10.1.1 Comparison of Secondary Metabolites with Primary
Metabolites
Primary metabolites are available in all types of plants and they perform all essential
metabolic reactions by sharing in nutrition, as well as reproduction (Croteau et al.
2000). In some cases, it is difficult to differentiate primary and secondary metabolites
of plant origin. Under the class of terpenoids, both primary and secondary metabolites
are available. The same phytoconstituent exhibits the role of both primary and secondary metabolites. Actually, secondary metabolites contain a lot of phytoconstituents derived from various plant families in environmental stress conditions that
show varieties of activity. Cell pigmentation in seed and flower provided by flavonoids and carotenoids (basically secondary metabolites) shows activities like primary
metabolites such as the attraction of pollinators and dispersion of seed and they have,
therefore, also involved in plant reproduction (Winkel-Shirley 2001). Plant primary
products are mainly glucose, nucleic acids, amino acids, proteins, carbohydrates, fats,
and lipids and they are concerned with the structure, physiology, and genetics of the
plant, which indicate their significant role in plant development. On the other hand,
secondary products are available in very few numbers and also in less concentrations
with comparison to primary metabolites. The production of carboxylic acids of the
Krebs cycle is under the involvement of primary metabolism. In contrast, secondary
metabolites are involved in providing fitness for survival to the plant species. The
particular phytoconstituents in a certain species have been used to determine systematically the groups of secondary plant products that are used to classify the plants
on the basis of the chemotaxonomic process (Winkel-Shirley 2001).
Plants produce an amazing diversity of low molecular weight compounds.
Among the estimated 400,000–500,000 plant species in World, only a small percentage of plants have experimented phytochemically and a small fraction is subjected to biological or pharmacological screening. The capability to produce
secondary plant products has been determined through the evolution of different
plant progeny when they faced surrounding stresses:
(a) Floral scent volatiles and pigments have developed to attract insect pollinators
and thus enhance fertilization that is involved in reproduction.
(b) Preparation of toxic chemicals to safeguard the pathogens and herbivores or to
inhibit the development of neighboring plants.
(c) Chemicals found in fruits inhibit spoilage of fruits and provide signals in the
form of color, aroma, and flavor to prove the presence of significant materials
332
C. C. Kandar
UV irradiation. They are manufactured for pharmaceutical benefits, for example, as
oleoresins and gum, e.g., gossypol. Gossypol is useful for male antifertility activity
and insecticidal activity (Kaur 2010).
10.1.1 Comparison of Secondary Metabolites with Primary
Metabolites
Primary metabolites are available in all types of plants and they perform all essential
metabolic reactions by sharing in nutrition, as well as reproduction (Croteau et al.
2000). In some cases, it is difficult to differentiate primary and secondary metabolites
of plant origin. Under the class of terpenoids, both primary and secondary metabolites
are available. The same phytoconstituent exhibits the role of both primary and secondary metabolites. Actually, secondary metabolites contain a lot of phytoconstituents derived from various plant families in environmental stress conditions that
show varieties of activity. Cell pigmentation in seed and flower provided by flavonoids and carotenoids (basically secondary metabolites) shows activities like primary
metabolites such as the attraction of pollinators and dispersion of seed and they have,
therefore, also involved in plant reproduction (Winkel-Shirley 2001). Plant primary
products are mainly glucose, nucleic acids, amino acids, proteins, carbohydrates, fats,
and lipids and they are concerned with the structure, physiology, and genetics of the
plant, which indicate their significant role in plant development. On the other hand,
secondary products are available in very few numbers and also in less concentrations
with comparison to primary metabolites. The production of carboxylic acids of the
Krebs cycle is under the involvement of primary metabolism. In contrast, secondary
metabolites are involved in providing fitness for survival to the plant species. The
particular phytoconstituents in a certain species have been used to determine systematically the groups of secondary plant products that are used to classify the plants
on the basis of the chemotaxonomic process (Winkel-Shirley 2001).
Plants produce an amazing diversity of low molecular weight compounds.
Among the estimated 400,000–500,000 plant species in World, only a small percentage of plants have experimented phytochemically and a small fraction is subjected to biological or pharmacological screening. The capability to produce
secondary plant products has been determined through the evolution of different
plant progeny when they faced surrounding stresses:
(a) Floral scent volatiles and pigments have developed to attract insect pollinators
and thus enhance fertilization that is involved in reproduction.
(b) Preparation of toxic chemicals to safeguard the pathogens and herbivores or to
inhibit the development of neighboring plants.
(c) Chemicals found in fruits inhibit spoilage of fruits and provide signals in the
form of color, aroma, and flavor to prove the presence of significant materials
332
C. C. Kandar