related disorders (CHD,CAD) and other diseases also because seafood has a very
low content of saturated fatty acid and higher content of omega-3 fatty acids. The
main reason of a high amount of PUFA in fishes is because of their daily consumption of algae where the synthesis of long-chain PUFA takes place (Aneiros
and Garateix 2004).
Eicosapentenoic (EPA) acid and docosahexenoic (DHA) acid are the examples
of Omega-3 fatty acid that is mainly found in the brain, cerebral cortex, skin, retinal
part of the human body system. They can be synthesized in the human body from
their precursor alpha-linolenic acid (ALA), but the rate of conversion is very low
because of the insufficient amount of the enzyme Δ6-desaturase (Dharmaraj et al.
2009). That’s why PUFA is taken in diet from marine food (fish oil, algae oil, etc.)
or other food resources. In Fig. 17.1 the synthesis process of Eicosapentenoic acid
and docosahexenoic acid are illustrated. There are so many examples of marine
sources available which enrich PUFA, EPA, DHA, etc. For example, salmon,
swordfish and halibut are excellent sources of PUFA (EPA, DPA, DHA) with
respective average levels of 1434, 3625, 3358, 2654 mg-PUFAs/100 g fw (Ma
et al. 2008).
Also, C. Vulgaris, the microalgae is enriched with oleic acid, palmitic acid and
linolenic acid. Haematococcus, a green microalgae includes short-chain fatty acids
and exhibits antimicrobial activity (Sijtsma et al. 2004). Figure 17.2 exemplify
various marine sources with the fatty acid profiles (LøvstadHoldt and Kraan 2011).
17.2.3 Sterols
These are another class of lipids that are also found in marine food. On experimental
studies, it has been noticed that the sterols which are extracted from macro and
microalgae, fish and other marine invertebrates (like corals, molluscs, sponges) are
capable of lowering the level of LDC (low- density lipoprotein) and also show
anti-inflammation bioactivity (Wall et al. 2010). Sargasseum ringgoldianum (brown
algae) has been reported to have various types of sterols in which saringosterol is
associated with anti-tubercular activity. Pelvetia siliquosa (marine algae) has also
been reported to have fucosterol and anti-oxidant activity (Pal 2013; Nimse and Pal
2015). Phytosterols (C28 and C29 sterols) are essential precursors of some vitamins.
For instance, ergosterol is a precursor of vitamin D2 and cortisone. Clionasterol
which is found in Spirulina is associated with increasing PAF in vascular endothelial
cells. Fucosterol, which is isolated from P. Siliquosa exhibits potent anti-diabetic
activity at a dose level of 100 and 300 mg/kg. It also decreases the glycogen
degradation of mouse liver by 23–29% (Wang et al. 2006). Various sterols with their
sources are mentioned In Table 17.3 (Özyurt et al. 2013).
17 Biological Activities of Marine Products …
591
low content of saturated fatty acid and higher content of omega-3 fatty acids. The
main reason of a high amount of PUFA in fishes is because of their daily consumption of algae where the synthesis of long-chain PUFA takes place (Aneiros
and Garateix 2004).
Eicosapentenoic (EPA) acid and docosahexenoic (DHA) acid are the examples
of Omega-3 fatty acid that is mainly found in the brain, cerebral cortex, skin, retinal
part of the human body system. They can be synthesized in the human body from
their precursor alpha-linolenic acid (ALA), but the rate of conversion is very low
because of the insufficient amount of the enzyme Δ6-desaturase (Dharmaraj et al.
2009). That’s why PUFA is taken in diet from marine food (fish oil, algae oil, etc.)
or other food resources. In Fig. 17.1 the synthesis process of Eicosapentenoic acid
and docosahexenoic acid are illustrated. There are so many examples of marine
sources available which enrich PUFA, EPA, DHA, etc. For example, salmon,
swordfish and halibut are excellent sources of PUFA (EPA, DPA, DHA) with
respective average levels of 1434, 3625, 3358, 2654 mg-PUFAs/100 g fw (Ma
et al. 2008).
Also, C. Vulgaris, the microalgae is enriched with oleic acid, palmitic acid and
linolenic acid. Haematococcus, a green microalgae includes short-chain fatty acids
and exhibits antimicrobial activity (Sijtsma et al. 2004). Figure 17.2 exemplify
various marine sources with the fatty acid profiles (LøvstadHoldt and Kraan 2011).
17.2.3 Sterols
These are another class of lipids that are also found in marine food. On experimental
studies, it has been noticed that the sterols which are extracted from macro and
microalgae, fish and other marine invertebrates (like corals, molluscs, sponges) are
capable of lowering the level of LDC (low- density lipoprotein) and also show
anti-inflammation bioactivity (Wall et al. 2010). Sargasseum ringgoldianum (brown
algae) has been reported to have various types of sterols in which saringosterol is
associated with anti-tubercular activity. Pelvetia siliquosa (marine algae) has also
been reported to have fucosterol and anti-oxidant activity (Pal 2013; Nimse and Pal
2015). Phytosterols (C28 and C29 sterols) are essential precursors of some vitamins.
For instance, ergosterol is a precursor of vitamin D2 and cortisone. Clionasterol
which is found in Spirulina is associated with increasing PAF in vascular endothelial
cells. Fucosterol, which is isolated from P. Siliquosa exhibits potent anti-diabetic
activity at a dose level of 100 and 300 mg/kg. It also decreases the glycogen
degradation of mouse liver by 23–29% (Wang et al. 2006). Various sterols with their
sources are mentioned In Table 17.3 (Özyurt et al. 2013).
17 Biological Activities of Marine Products …
591