291
Many variables such as variations in grain types, germination conditions along
with laboratory technologies may confused the findings. Due to these variable
results achieved after germination of same type of whole grain could be changed
(decrease or increase) or unchanged. Such as amount of sugar were resulted both
increase or decrease when compare with control group (un-germinated) while different results were showed by using different type of rice varieties. (Moongngarm
and Saetung 2010). Related results were also found in another study in which antioxidant ability of sprouted rice resulted both increase and decrease, antioxidant
activity was measured by using scavenging activity of the rice variety (Imam et al.
2012). Due to above mentioned reasons care should be taken during comparison of
the results from other studies. It proved from previous discussion that optimum
conditions might be varied with grain type, parameter to be studied and analytical
techniques being used for analysis. The degree of the variation detected may change
with other parameters like temperature, time, moisture, available oxygen for germination (Koehler et al. 2007), type of whole grain and environmental conditions
(Mak et al. 2009).
If talk about life-cycle of the cereals grains it comprised upon two phases which
were separated from each other by dormancy i.e. germination and development.
During germination seeds play a vital role as a reproductive unit and this unit guarantees survival of all species of plants. There are three distinct parts of the wheat
grains namely endosperm, bran layer (sometime called peripheral layer) which
comprised of aleurone, nucleus tegument, testa and pericarp, and important part
germ which is comprised of embryos and scutellum (Tasleem-Tahir et al. 2011). As
the germination process starts complex compound present in grain like carbohydrates, protein and lipids are converted to simple and soluble molecules by the
action of various enzymes which are present in the kernel. These enzymes usually
stimulate upon germination. Mostly such enzymes present in upper aleurone layer,
bran and in germ (Poutanen 1997). For example, amylase enzyme required to breakdown complex starch usually present in the pericarp. Another important enzyme
required to break-down complex protein (proteases) are present in endosperm, germ
and aleurone layer. Lipoxygenase enzyme which break-down fats is dominantly
present in embryo, while polyphenol oxidase and peroxidase are dominantly present in bran of seeds (Rani et al. 2011). These enzymes convert complex compounds
into simple fractions which initiate the complex physiological and bio-chemical
changes in the seeds.
16.6 Bioactive Compounds
A vast number of organic compounds are produced by the plants and these organic
compounds didn’t take part directly in growth and development of the plants.
Conventionally, such compounds are called secondary metabolites and are found in
various amounts in taxonomic group of plants. In contrast, secondary metabolites
plant also produced primary metabolites such as acyl acids, phytosterols, organic
16 Effect of Germination Processing on Bioactive Compounds of Cereals and Legumes
Many variables such as variations in grain types, germination conditions along
with laboratory technologies may confused the findings. Due to these variable
results achieved after germination of same type of whole grain could be changed
(decrease or increase) or unchanged. Such as amount of sugar were resulted both
increase or decrease when compare with control group (un-germinated) while different results were showed by using different type of rice varieties. (Moongngarm
and Saetung 2010). Related results were also found in another study in which antioxidant ability of sprouted rice resulted both increase and decrease, antioxidant
activity was measured by using scavenging activity of the rice variety (Imam et al.
2012). Due to above mentioned reasons care should be taken during comparison of
the results from other studies. It proved from previous discussion that optimum
conditions might be varied with grain type, parameter to be studied and analytical
techniques being used for analysis. The degree of the variation detected may change
with other parameters like temperature, time, moisture, available oxygen for germination (Koehler et al. 2007), type of whole grain and environmental conditions
(Mak et al. 2009).
If talk about life-cycle of the cereals grains it comprised upon two phases which
were separated from each other by dormancy i.e. germination and development.
During germination seeds play a vital role as a reproductive unit and this unit guarantees survival of all species of plants. There are three distinct parts of the wheat
grains namely endosperm, bran layer (sometime called peripheral layer) which
comprised of aleurone, nucleus tegument, testa and pericarp, and important part
germ which is comprised of embryos and scutellum (Tasleem-Tahir et al. 2011). As
the germination process starts complex compound present in grain like carbohydrates, protein and lipids are converted to simple and soluble molecules by the
action of various enzymes which are present in the kernel. These enzymes usually
stimulate upon germination. Mostly such enzymes present in upper aleurone layer,
bran and in germ (Poutanen 1997). For example, amylase enzyme required to breakdown complex starch usually present in the pericarp. Another important enzyme
required to break-down complex protein (proteases) are present in endosperm, germ
and aleurone layer. Lipoxygenase enzyme which break-down fats is dominantly
present in embryo, while polyphenol oxidase and peroxidase are dominantly present in bran of seeds (Rani et al. 2011). These enzymes convert complex compounds
into simple fractions which initiate the complex physiological and bio-chemical
changes in the seeds.
16.6 Bioactive Compounds
A vast number of organic compounds are produced by the plants and these organic
compounds didn’t take part directly in growth and development of the plants.
Conventionally, such compounds are called secondary metabolites and are found in
various amounts in taxonomic group of plants. In contrast, secondary metabolites
plant also produced primary metabolites such as acyl acids, phytosterols, organic
16 Effect of Germination Processing on Bioactive Compounds of Cereals and Legumes