292
acids and amino acids which are produced by all types of plants and participate
essentially in development and growth of the plant (Hussain et al. 2012). Secondary
metabolites which are limitedly produced by the plants have complex structure and
biosynthetic pathways and conventionally these compounds didn’t get much intentions of the researchers as these compounds are taken biologically insignificant
(Parsaeimehr et al. 2011).
In contrast to biochemists, pharmaceutical researchers gave much intention to
secondary metabolites (organic compounds) and since 1850s they intensively investigated their biochemical properties. Interestingly, investigation on these bioactive
compounds was not just on academic level but on industrial level several compounds were developed from these bioactive components, few examples are dyes,
polymers, fibers, glues, oils, waxes, flavoring agents, perfumes, and drugs. These
compounds have huge biochemical properties due to which researchers focused to
develop innovative drug, herbicides, insecticides and antibiotics (Grindberg
et al. 2011).
Based on their synthetic pathways, these compounds are divided into three major
categories (nitrogen containing compounds, terpenes and phenolics) (Krzyzanowska
et al. 2010). Research had been conducted on their mechanism of synthesis including firstly the mevalonic pathway (to synthesize terpenes), secondly shikimic acid
pathway or the mevalonic pathway (to synthesize phenolic compounds), thirdly tricarboxilic acid pathway (to synthesize nitrogen containing secondary metabolites).
In pharmaceutical industry, vast number of products are produced by using these
secondary metabolites (Parsaeimehr et al. 2011).
16.7 Phenolic Compounds
In numerous studies, (Table 16.3) polyphenolic compounds recognized as major
antioxidant components of the whole grains (Zieli’nski and Kozłowska 2000).
Radical compounds produced from oxidation are stabilized by the phenolic compounds as phenolic compounds are antioxidant in nature. Whole grains contain
large amount of antioxidant compounds, few examples of such compounds are vitamins, sterols, and phenolics as well as phytic acid. Above mentioned compounds
mostly found in bran or germ of the whole grain (Fardet et al. 2008). All these
mentioned bioactive compounds are participated in degree of antioxidant properties
and germination process also affect such compounds. Various in vitro studies
showed the antioxidant effect of these compounds however, in vivo antioxidant
effect is not completely recognized yet (Fardet et al. 2008). It is interesting to know
that few bioactive compounds might act as synergists/antagonists, having antioxidant characteristics in-vitro, might not observed of such compounds in-vivo.
Polyphenols primarily occur in both soluble or bound forms in plants but edible
grains mostly have high ratio of bound phenolics (Agati et al. 2012).
Polyphenolic contents (secondary metabolites) produced by plants contains variety of structurally and functionally diverse compounds which are produced through
S. Hassan et al.
acids and amino acids which are produced by all types of plants and participate
essentially in development and growth of the plant (Hussain et al. 2012). Secondary
metabolites which are limitedly produced by the plants have complex structure and
biosynthetic pathways and conventionally these compounds didn’t get much intentions of the researchers as these compounds are taken biologically insignificant
(Parsaeimehr et al. 2011).
In contrast to biochemists, pharmaceutical researchers gave much intention to
secondary metabolites (organic compounds) and since 1850s they intensively investigated their biochemical properties. Interestingly, investigation on these bioactive
compounds was not just on academic level but on industrial level several compounds were developed from these bioactive components, few examples are dyes,
polymers, fibers, glues, oils, waxes, flavoring agents, perfumes, and drugs. These
compounds have huge biochemical properties due to which researchers focused to
develop innovative drug, herbicides, insecticides and antibiotics (Grindberg
et al. 2011).
Based on their synthetic pathways, these compounds are divided into three major
categories (nitrogen containing compounds, terpenes and phenolics) (Krzyzanowska
et al. 2010). Research had been conducted on their mechanism of synthesis including firstly the mevalonic pathway (to synthesize terpenes), secondly shikimic acid
pathway or the mevalonic pathway (to synthesize phenolic compounds), thirdly tricarboxilic acid pathway (to synthesize nitrogen containing secondary metabolites).
In pharmaceutical industry, vast number of products are produced by using these
secondary metabolites (Parsaeimehr et al. 2011).
16.7 Phenolic Compounds
In numerous studies, (Table 16.3) polyphenolic compounds recognized as major
antioxidant components of the whole grains (Zieli’nski and Kozłowska 2000).
Radical compounds produced from oxidation are stabilized by the phenolic compounds as phenolic compounds are antioxidant in nature. Whole grains contain
large amount of antioxidant compounds, few examples of such compounds are vitamins, sterols, and phenolics as well as phytic acid. Above mentioned compounds
mostly found in bran or germ of the whole grain (Fardet et al. 2008). All these
mentioned bioactive compounds are participated in degree of antioxidant properties
and germination process also affect such compounds. Various in vitro studies
showed the antioxidant effect of these compounds however, in vivo antioxidant
effect is not completely recognized yet (Fardet et al. 2008). It is interesting to know
that few bioactive compounds might act as synergists/antagonists, having antioxidant characteristics in-vitro, might not observed of such compounds in-vivo.
Polyphenols primarily occur in both soluble or bound forms in plants but edible
grains mostly have high ratio of bound phenolics (Agati et al. 2012).
Polyphenolic contents (secondary metabolites) produced by plants contains variety of structurally and functionally diverse compounds which are produced through
S. Hassan et al.