sphaericum and Parachlorella kessleri are good for astaxanthin production.
Table 4.8 shows the contents of carotenoids from each studied microalga species.
Among the microalgae, Chlorella genus is one of the major sources of chlorophyll pigment which can provide health benefits such as healing of sores, ulcers,
hemorrhoids, regulation of menstruation, helpful in hemophilia, and improves
diabetes and asthma (Rani et al. 2018).
Kulkarni and Nikolov (2018) studied a selective extraction of carotenoids and
chlorophylls from Chlorella vulgaris, and they identified lutein and chlorophyll
(a and b), respectively 5.4 mg/g dry mass and 15.4 mg/g dry mass.
Regarding astaxanthin pigment, the green microalgae Haematococcus pluvialis is
one of its most important biological sources (Cuellar-Bermudez et al. 2015),
representing around 90% of total carotenoids (Borowitzka 2013), and Fig. 4.4
shows the metabolic pathway of astaxanthin production from β-carotene in the
microalgae.
In addition, in many applications that were already cited, microalgae can also be
used in aquaculture products, for instance, as feed for salmon (Spolaore et al. 2006).
4.5.8 Polysaccharides
Polysaccharides are polymeric carbohydrate molecules that are commonly applied in
food industry (Andrade et al. 2018) which can present anti-inflammatory, antiviral,
anticancer, and antioxidant properties (Dufossé et al. 2005; Herrero et al. 2005;
Sheng et al. 2007).
Similar to pigments, stress conditions can influence the biosynthesis of the polysaccharides, in this case increasing its content (Dufossé et al. 2005).
Pugh et al. (2001) identified three polysaccharides from Spirulina platensis,
Aphanizomenon flos-aquae, and Chlorella pyrenoidosa: immulina, immunon, and
immurella, respectively. Comprising between 0.5% and 2% of the microalgal dry
weight, those polysaccharides are between 100 and 1000 times more active than that
are currently used for cancer immunotherapy.
Bernaerts et al. (2018) studied the cell wall–related polysaccharides of ten
microalgae species (Arthrospira platensis, Chlorella vulgaris, Diacronema lutheri,
Tisochrysis lutea, Nannochloropsis sp., Odontella aurita, Phaeodactylum
tricornutum, Porphyridium cruentum, Schizochytrium sp., and Tetraselmis chuii)
with potential as functional food ingredients. They observed that Arthrospira
platensis and Chlorella vulgaris are mainly composed of proteins and polysaccharides. The polysaccharides correspond to 10% of the biomass and containing uronic
acid and sulfate groups that provide anionic characteristics. Table 4.9 shows the
characteristics of the monosaccharide and uronic acid composition in cell wall
polysaccharides of microalgae.
For many years, Nostoc genus microalgae have been used as food and medicine.
Its composition rich in polysaccharides provides a very good resistance to several
environmental stresses, as oxidative stress. Li et al. (2018) isolated a polysaccharide
4 Phycoremediation: A Sustainable Biorefinery Approach
121
Table 4.8 shows the contents of carotenoids from each studied microalga species.
Among the microalgae, Chlorella genus is one of the major sources of chlorophyll pigment which can provide health benefits such as healing of sores, ulcers,
hemorrhoids, regulation of menstruation, helpful in hemophilia, and improves
diabetes and asthma (Rani et al. 2018).
Kulkarni and Nikolov (2018) studied a selective extraction of carotenoids and
chlorophylls from Chlorella vulgaris, and they identified lutein and chlorophyll
(a and b), respectively 5.4 mg/g dry mass and 15.4 mg/g dry mass.
Regarding astaxanthin pigment, the green microalgae Haematococcus pluvialis is
one of its most important biological sources (Cuellar-Bermudez et al. 2015),
representing around 90% of total carotenoids (Borowitzka 2013), and Fig. 4.4
shows the metabolic pathway of astaxanthin production from β-carotene in the
microalgae.
In addition, in many applications that were already cited, microalgae can also be
used in aquaculture products, for instance, as feed for salmon (Spolaore et al. 2006).
4.5.8 Polysaccharides
Polysaccharides are polymeric carbohydrate molecules that are commonly applied in
food industry (Andrade et al. 2018) which can present anti-inflammatory, antiviral,
anticancer, and antioxidant properties (Dufossé et al. 2005; Herrero et al. 2005;
Sheng et al. 2007).
Similar to pigments, stress conditions can influence the biosynthesis of the polysaccharides, in this case increasing its content (Dufossé et al. 2005).
Pugh et al. (2001) identified three polysaccharides from Spirulina platensis,
Aphanizomenon flos-aquae, and Chlorella pyrenoidosa: immulina, immunon, and
immurella, respectively. Comprising between 0.5% and 2% of the microalgal dry
weight, those polysaccharides are between 100 and 1000 times more active than that
are currently used for cancer immunotherapy.
Bernaerts et al. (2018) studied the cell wall–related polysaccharides of ten
microalgae species (Arthrospira platensis, Chlorella vulgaris, Diacronema lutheri,
Tisochrysis lutea, Nannochloropsis sp., Odontella aurita, Phaeodactylum
tricornutum, Porphyridium cruentum, Schizochytrium sp., and Tetraselmis chuii)
with potential as functional food ingredients. They observed that Arthrospira
platensis and Chlorella vulgaris are mainly composed of proteins and polysaccharides. The polysaccharides correspond to 10% of the biomass and containing uronic
acid and sulfate groups that provide anionic characteristics. Table 4.9 shows the
characteristics of the monosaccharide and uronic acid composition in cell wall
polysaccharides of microalgae.
For many years, Nostoc genus microalgae have been used as food and medicine.
Its composition rich in polysaccharides provides a very good resistance to several
environmental stresses, as oxidative stress. Li et al. (2018) isolated a polysaccharide
4 Phycoremediation: A Sustainable Biorefinery Approach
121