4.4 Food Supplements
Cyanobacteria as food supplements are available in the market in different forms
such as tablets, capsules, and liquid. They enhance the nutritive value of foods and
beverages (Liang et al. 2004). They can act as the nutritional supplement or represent
a source of natural food colorants (Soletto et al. 2005). Spirulina is the most
commercial cyanobacterial strain used for human nutrition because of its highprotein content and excellent nutritive value (Soletto et al. 2005). It contains more
than 60% proteins and is rich in beta-carotene, thiamine, and riboflavin and is
considered to be one of the richest sources of vitamin B 12 (Prasanna et al. 2010).
Spirulina contains a wide spectrum of prophylactic and therapeutic nutrients including B-complex vitamins, minerals, proteins, γ-linolenic acid, and super antioxidants
such as β-carotene, vitamin E, trace elements, and a number of unexplored bioactive
compounds (Kulshreshtha et al. 2008).
4.5 Bio-control Agents
Cyanobacteria produce a variety of biologically active compounds of antibacterial,
antifungal, antialgal, and antiviral potential (Dahms et al. 2006). These bioactive
compounds belong to the group of polyketides, amides, alkaloids, fatty acids,
indoles, and lipopeptides (Burja et al. 2001). In addition cyanobacteria produce a
broad spectrum of antialgal compounds which inhibit growth of pathogens by
disturbing their metabolic and physiological activities (Dahms et al. 2006). The
excretion of bioactive compounds by cyanobacteria into the aquatic environments is
a possible allelopathy strategy used by cyanobacteria to outcompete other microorganisms within the same ecosystem (Gross 2006). To date, several allelochemicals
from cyanobacteria have been identified, and they include cyanobacteria produced
by Scytonema hofmanni, enediyne-containing photosystem II inhibitor synthesized
by Fischerella muscicola, hapalindoles that are isolated from Hapalosiphon and
Fischerella sp., and nostocyclamides from Nostoc sp.
4.6 Emulsifiers
Some halophilic cyanobacteria produce large amounts of exopolysaccharides (EPS),
which are used for oil recovery by decreasing its surface tension and increasing its
solubility and mobility. EPS, when gelated under alkaline conditions, was employed
to remove dyes from textile effluent. The halophilic cyanobacterium Aphanocapsa
halophytica was used for the production of EPS (Matsunaga et al. 1996).
16 Cyanobacteria: The Eco-Friendly Tool for the Treatment of Industrial Wastewaters
405
Cyanobacteria as food supplements are available in the market in different forms
such as tablets, capsules, and liquid. They enhance the nutritive value of foods and
beverages (Liang et al. 2004). They can act as the nutritional supplement or represent
a source of natural food colorants (Soletto et al. 2005). Spirulina is the most
commercial cyanobacterial strain used for human nutrition because of its highprotein content and excellent nutritive value (Soletto et al. 2005). It contains more
than 60% proteins and is rich in beta-carotene, thiamine, and riboflavin and is
considered to be one of the richest sources of vitamin B 12 (Prasanna et al. 2010).
Spirulina contains a wide spectrum of prophylactic and therapeutic nutrients including B-complex vitamins, minerals, proteins, γ-linolenic acid, and super antioxidants
such as β-carotene, vitamin E, trace elements, and a number of unexplored bioactive
compounds (Kulshreshtha et al. 2008).
4.5 Bio-control Agents
Cyanobacteria produce a variety of biologically active compounds of antibacterial,
antifungal, antialgal, and antiviral potential (Dahms et al. 2006). These bioactive
compounds belong to the group of polyketides, amides, alkaloids, fatty acids,
indoles, and lipopeptides (Burja et al. 2001). In addition cyanobacteria produce a
broad spectrum of antialgal compounds which inhibit growth of pathogens by
disturbing their metabolic and physiological activities (Dahms et al. 2006). The
excretion of bioactive compounds by cyanobacteria into the aquatic environments is
a possible allelopathy strategy used by cyanobacteria to outcompete other microorganisms within the same ecosystem (Gross 2006). To date, several allelochemicals
from cyanobacteria have been identified, and they include cyanobacteria produced
by Scytonema hofmanni, enediyne-containing photosystem II inhibitor synthesized
by Fischerella muscicola, hapalindoles that are isolated from Hapalosiphon and
Fischerella sp., and nostocyclamides from Nostoc sp.
4.6 Emulsifiers
Some halophilic cyanobacteria produce large amounts of exopolysaccharides (EPS),
which are used for oil recovery by decreasing its surface tension and increasing its
solubility and mobility. EPS, when gelated under alkaline conditions, was employed
to remove dyes from textile effluent. The halophilic cyanobacterium Aphanocapsa
halophytica was used for the production of EPS (Matsunaga et al. 1996).
16 Cyanobacteria: The Eco-Friendly Tool for the Treatment of Industrial Wastewaters
405