Biomedical Engineering Reference
In-Depth Information
of photosynthetic complexes in plants and microalgae (Pulz and Gross, 2004;
Del Campo, 2007). They occur widely in nature and are responsible for many of
the brilliant red, orange, and yellow colors of edible vegetables and fruits and some
aquaculture animals.
Microalgae combine properties of higher plants with some properties of prokary-
otes. This combination represents the rationale for using microalgae for the pro-
duction of carotenoids and other products (Del Campo, 2007; Guedes et al., 2011)
instead of using plants or prokaryotes. Furthermore, the production of carotenoids
by microalgae can be easily maximized by manipulating growth conditions. Under
unfavorable growth conditions, microalgae produce high amounts of carotenoids,
such as β-carotene, astaxanthin, and canthaxanthin (Orosa et al., 2000).
10.2.1.1 Commercial Applications
There is a demand for natural pigments to be applied in the food, pharmaceuti-
cal, and aquaculture industries (Dufossé et al., 2005). The use of synthetic dyes in
these industries is slowly declining due to their toxic effects (Dufossé et al., 2005).
Compared to synthetic alternatives, microalgal carotenoids have the advantage of
supplying natural isomers in their natural ratios (Pulz and Gross, 2004; Milledge,
2011). Microalgal pigments have been used as alternatives to synthetic pigments in
various industries (Table 10.2).
Other than for coloring purposes, carotenoids have recently been used as anti-
oxidants. Carotenoids have antioxidant effects that can be beneficial in countering
diseases such as cancer, obesity, and hypertension (Inbaraj et al., 2006; Murthy et al.,
2005). Table 10.3 indicates the applications of commercially exploited carotenoids
in various industries.
The worldwide demand for carotenoids has been increasing at an average yearly
rate of 2.2% (Guedes et al., 2011). Among the 400 known carotenoids, so far only
a few have been exploited (Cosgrove, 2010; Milledge, 2011). The two most com-
monly exploited algal carotenoids are β-carotene and astaxanthin, which are
mainly produced by Dunaliella salina and Haematococcus pluvialis, respectively
(Pulz and Gross, 2004; Spolaore et al., 2006; Del Campo, 2007; Cosgrove 2010;
TABLE 10.2
Utilization of Microalgae for Production of Natural Pigments
Production
System
Products Used as
Natural Pigments
Microalgal Strain
Ref.
Spirulina
Open pond
Phycocyanin
Dufossé et al., 2005
Dunaliella salina
Open pond
β-Carotene
Dufossé et al., 2005;
Del Campo et al., 2007
Haematococcus
pluvialis
Open pond
Astaxanthin
Dufossé et al., 2005;
Del Campo et al., 2007
Muriellopsis sp.
Open pond
Lutein
Dufossé et al., 2005;
Del Campo et al., 2007
 
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