Arthrospira is widely used for nutritional purposes (Soletto et al. 2005; Spolaore
et al. 2006). Apart from this, the microalgae are also used for other health benefits,
namely, growth promotion, suppression of hypertension, prevention of renal
diseases, relief from hyperlipidemia, and reduction in the increased level of serum
glucose (Liang et al. 2004; Spolaore et al. 2006).
Edible algae include the microalgal species Chlorella and Spirulina. These algae
are widely studied for their biological activities and component molecules (Pulz and
Gross 2004; Mata et al. 2010). Spirulina platensis and Spirulina maxima are widely
used for human consumption owing to the various benefits offered by them, namely,
boosting the immune system, prevention of cancer and viral infections, and rise in
the number of intestinal lactates (Mata et al. 2010). The polysaccharide complexes
from Chlorella pyrenoidosa and Chlorella ellipsoidea possess immunomodulatory
characteristics (Barrow and Shahidi 2008; Mata et al. 2010). Various species of
microalgae such as N. oculata, Thalassiosira pseudonana, and Phaeodactylum
tricornutum have the capability to produce varying amounts of long-chain polyunsaturated fatty acids (PUFAs) that have a vital therapeutic and dieticiary role (Pulz
and Gross 2004; Kumar et al. 2019). Euglena gracilis and Prototheca moriformis are
widely cultivated for the production of biotin, tocopherol, and ascorbic acid, respectively (Li et al. 2008; Patel et al. 2017). It also promotes antibody production and is
thus a potential immunomodulator. Moreover, it is also associated with prevention of
onset of cancer in the oral cavity, liver, and bladder (Mata et al. 2010).
8.7.10 Aquaculture
Microalgae are widely used in the aquaculture processes and are cultivated by two
main methods: natural phytoplankton and algal monocultures. In natural phytoplankton, various nutrients are added to enrich the population of phytoplankton
that are found naturally or in the form of cultures (Mata et al. 2010). However, this
process of using natural phytoplanktons has many drawbacks including variable
composition of algal populations, amount of nutrients available, hindrance from
undesirable predators, presence of other contaminating species, and lack of monitoring and control over the production process. In case of monoculture cultivation
of microalgae feed source of high quality with known nutritional properties, the
desired algal cultures free of contamination from unwanted species are utilized.
The major obstruction to monoculture cultivation is that the microalgae species are
subjected to a large number of predators such as the crustaceans, protozoans
(zooflagellates or rhizopods), larvae of benthic organisms and infection by viruses,
bacteria, or fungi when cultivated on a larger scale. Predation by various types of
protozoans and the high possibility of formation of toxic algal blooms are major
problems associated with marine microalgae culture. For instance, growth of
Synechocystis in freshwater and Phaeodactylum in seawater is unenviable for the
bivalve mollusks (Mata et al. 2010).
8 Algal Biomass: Potential Renewable Feedstock for Biofuels Production – Part I
227
et al. 2006). Apart from this, the microalgae are also used for other health benefits,
namely, growth promotion, suppression of hypertension, prevention of renal
diseases, relief from hyperlipidemia, and reduction in the increased level of serum
glucose (Liang et al. 2004; Spolaore et al. 2006).
Edible algae include the microalgal species Chlorella and Spirulina. These algae
are widely studied for their biological activities and component molecules (Pulz and
Gross 2004; Mata et al. 2010). Spirulina platensis and Spirulina maxima are widely
used for human consumption owing to the various benefits offered by them, namely,
boosting the immune system, prevention of cancer and viral infections, and rise in
the number of intestinal lactates (Mata et al. 2010). The polysaccharide complexes
from Chlorella pyrenoidosa and Chlorella ellipsoidea possess immunomodulatory
characteristics (Barrow and Shahidi 2008; Mata et al. 2010). Various species of
microalgae such as N. oculata, Thalassiosira pseudonana, and Phaeodactylum
tricornutum have the capability to produce varying amounts of long-chain polyunsaturated fatty acids (PUFAs) that have a vital therapeutic and dieticiary role (Pulz
and Gross 2004; Kumar et al. 2019). Euglena gracilis and Prototheca moriformis are
widely cultivated for the production of biotin, tocopherol, and ascorbic acid, respectively (Li et al. 2008; Patel et al. 2017). It also promotes antibody production and is
thus a potential immunomodulator. Moreover, it is also associated with prevention of
onset of cancer in the oral cavity, liver, and bladder (Mata et al. 2010).
8.7.10 Aquaculture
Microalgae are widely used in the aquaculture processes and are cultivated by two
main methods: natural phytoplankton and algal monocultures. In natural phytoplankton, various nutrients are added to enrich the population of phytoplankton
that are found naturally or in the form of cultures (Mata et al. 2010). However, this
process of using natural phytoplanktons has many drawbacks including variable
composition of algal populations, amount of nutrients available, hindrance from
undesirable predators, presence of other contaminating species, and lack of monitoring and control over the production process. In case of monoculture cultivation
of microalgae feed source of high quality with known nutritional properties, the
desired algal cultures free of contamination from unwanted species are utilized.
The major obstruction to monoculture cultivation is that the microalgae species are
subjected to a large number of predators such as the crustaceans, protozoans
(zooflagellates or rhizopods), larvae of benthic organisms and infection by viruses,
bacteria, or fungi when cultivated on a larger scale. Predation by various types of
protozoans and the high possibility of formation of toxic algal blooms are major
problems associated with marine microalgae culture. For instance, growth of
Synechocystis in freshwater and Phaeodactylum in seawater is unenviable for the
bivalve mollusks (Mata et al. 2010).
8 Algal Biomass: Potential Renewable Feedstock for Biofuels Production – Part I
227