19 Use of Microalgae Pigments in Aquaculture
487
with the astaxanthin extract, indicating that the microalgae biomass might have more
biomolecules contributing to the growth compared to the pure astaxanthin alone
(Table 19.2). In fact, whole microalgae biomass also improved immune capacity and
enhanced low salinity tolerance in Penaeus vannamei (Xie et al. 2018).
19.7.1 Carotenoids in Aquaculture
Nutritious and balanced diets can influence the immunity and disease resistance in
cultured animals and reduce disease-related economic loss. Dietary supplementation
with key amino acids, polyunsaturated fatty acids, vitamins and carotenoids were
critical in modulating immune response and productivity of the aquaculture industry
(Khatoon et al. 2007; Pohlenz and Gatlin 2014; Begum et al. 2016; Ahmad et al.
2019).
Carotenoids encompass approximately 1200 pigments categorized into two major
groups (carotenes and xanthophylls) and they are known as one of the most important
sets of compounds in improving growth and health of many organisms (Lockwood
et al. 2003; Paliwal et al. 2016; Heo et al. 2018; Wang et al. 2018b). Carotenoids are
synthesized by higher plants, mosses, bacteria, fungi and algae. However, there are
some pigments, such as fucoxanthin, which are only found in certain microalgae (Foo
et al. 2015, 2017). Most animals, with a few exceptions, do not produce carotenoids
de novo, but take them in their diets.
In aquaculture, carotenoids function in pigment development, antioxidants and
vitamin enrichment, growth and reproduction improvement, cellular protection from
photo-damage and health enhancement (Table 19.2). Due to their antioxidant and
free radical scavenging properties, the best known function of carotenoids in aquaculture besides increased growth and enhanced immunity (Lim et al. 2018) is pigmentation (Menasveta et al. 1993; Wade et al. 2017a). Colours play a major role in
improving perceived quality, acceptability and willingness to pay for aquaculture
products. Higuera-Ciapara et al. (2006) noted that orange-reddish colour is one of
the most important factors in the perceived quality of salmonids and crustaceans.
Since the colour of fish skin is an important factor in determining the retail value of
a commodity, Pavlidis et al. (2006) developed a new index, the Entire Colour Index
(ECI) to express the actual colour of the fish or invertebrates, which is influenced
by hue and chroma as a combined variable as these factors should not be considered
separately. Sun et al. (2012) reported that carotenoids showed better effects on skin
pigmentation compared to xanthophylls.
Colours in organisms are mainly determined by genetic inheritance, but the
pigmentation can be greatly influenced by environmental factors and occurrence of
diseases. Carotenoids, which are dependent on diets and body conditions, are responsible for many yellow, orange and red hues in animals including fish and aquatic
invertebrates (Sefc et al. 2014). Wade et al. (2017b) reported that 30–50 mg/kg body
weight of carotenoids is required to achieve optimal colours in penaeid shrimps. The
enhancement of colouration in fish can be due to the proliferation of chromatophores
487
with the astaxanthin extract, indicating that the microalgae biomass might have more
biomolecules contributing to the growth compared to the pure astaxanthin alone
(Table 19.2). In fact, whole microalgae biomass also improved immune capacity and
enhanced low salinity tolerance in Penaeus vannamei (Xie et al. 2018).
19.7.1 Carotenoids in Aquaculture
Nutritious and balanced diets can influence the immunity and disease resistance in
cultured animals and reduce disease-related economic loss. Dietary supplementation
with key amino acids, polyunsaturated fatty acids, vitamins and carotenoids were
critical in modulating immune response and productivity of the aquaculture industry
(Khatoon et al. 2007; Pohlenz and Gatlin 2014; Begum et al. 2016; Ahmad et al.
2019).
Carotenoids encompass approximately 1200 pigments categorized into two major
groups (carotenes and xanthophylls) and they are known as one of the most important
sets of compounds in improving growth and health of many organisms (Lockwood
et al. 2003; Paliwal et al. 2016; Heo et al. 2018; Wang et al. 2018b). Carotenoids are
synthesized by higher plants, mosses, bacteria, fungi and algae. However, there are
some pigments, such as fucoxanthin, which are only found in certain microalgae (Foo
et al. 2015, 2017). Most animals, with a few exceptions, do not produce carotenoids
de novo, but take them in their diets.
In aquaculture, carotenoids function in pigment development, antioxidants and
vitamin enrichment, growth and reproduction improvement, cellular protection from
photo-damage and health enhancement (Table 19.2). Due to their antioxidant and
free radical scavenging properties, the best known function of carotenoids in aquaculture besides increased growth and enhanced immunity (Lim et al. 2018) is pigmentation (Menasveta et al. 1993; Wade et al. 2017a). Colours play a major role in
improving perceived quality, acceptability and willingness to pay for aquaculture
products. Higuera-Ciapara et al. (2006) noted that orange-reddish colour is one of
the most important factors in the perceived quality of salmonids and crustaceans.
Since the colour of fish skin is an important factor in determining the retail value of
a commodity, Pavlidis et al. (2006) developed a new index, the Entire Colour Index
(ECI) to express the actual colour of the fish or invertebrates, which is influenced
by hue and chroma as a combined variable as these factors should not be considered
separately. Sun et al. (2012) reported that carotenoids showed better effects on skin
pigmentation compared to xanthophylls.
Colours in organisms are mainly determined by genetic inheritance, but the
pigmentation can be greatly influenced by environmental factors and occurrence of
diseases. Carotenoids, which are dependent on diets and body conditions, are responsible for many yellow, orange and red hues in animals including fish and aquatic
invertebrates (Sefc et al. 2014). Wade et al. (2017b) reported that 30–50 mg/kg body
weight of carotenoids is required to achieve optimal colours in penaeid shrimps. The
enhancement of colouration in fish can be due to the proliferation of chromatophores