364
M. C. Deprá et al.
Given this scenario, boosted by the favorable market, the intensification of the
research resulted in important discoveries, which made it possible to open up alternative or additional biotechnological processes for the industrial manufacture of
natural food colorants with enhanced functionalities (Tuli et al. 2015).
Thus, microalgae have emerged as an attractive alternative, since they are
microorganisms capable of naturally synthesized pigments such as chlorophylls,
carotenoids, and phycobiliproteins that exhibit several health-relevant properties
besides colorant, such as anti-viral, antimicrobial, anti-inflammatory, antioxidant,
pro-vitamin A, immunomodulatory and anticancer activities (Viera et al. 2018). In
terms of microalgae-based pigments that reached the commercial level, β-carotene
from Dunaliella salina, astaxanthin from Haematococcus pluvialis and phycocyanin
from Arthrospira platensis are molecules already approved as food ingredients by
main world regulatory organizations (EC EFSA 1997; MHLW 1996; ANVISA 2018;
FDA 2019).
However, in spite of the perceived advantages, a number of techno-economic
barriers need to be overcome for the consolidating of microalgae-based processes on a
commercial scale. In order to understand this processes performance, comprehensive
analyses addressing environmental, economic and social indicators should be carried
out following a life cycle perspective (Gong and Bassi 2016).
In this sense, the objective of this chapter is to perform a comparative life cycle
assessment of the current production scenarios of synthetic and microalgae-based
pigments with a focus on the establishment of sustainable metrics.
15.2 Synthetic Pigments
Chemical synthesis of pigments was developed by three teams independently in
the year 1950, being considered a milestone in the research of pigments (Karrer
and Eugster 1950; Inhoffen et al. 1950, Milas et al. 1950). In 1976, more than 90
naturally occurring pigments were synthesized based on this early work, through
the principle of coupling appropriate end groups to a central building block. During
this time some methods of chemical synthesis have been successfully developed to
obtain pigments and they have since been used repeatedly (Britton et al. 1996). Two
examples of these methods are illustrated in Figs. 15.1 and 15.2.
The first scaled up method developed by Hoffman-La Roche was the Roche
synthesis in 1954. With a yield of 60%, this method was based on the Grignard
reaction (enol ether condensation) and follows the C 19 + C 2 + C 19 synthesis principle (Fig. 15.1) (Ribeiro et al. 2011). By the glycidic ester synthesis, the ß-ionone is
lengthened to ß-C14-aldehyde. Through an alkali treatment, a CH 2 -group link to the
side chain of this aldehyde, thus undoing the double-bonded conjugate system of the
ring. Thus, the ß-C14-aldehyde is transformed into its acetal for chain lengthening,
being condensed with vinyl ether in the catalytic presence of an acid. Subsequent
hydrolysis gives the crystalline ß-C16-aldehyde. By a similar process, the β-C16
is converted with propenyl ether to the crystalline ß-C19-aldehyde. Through the
M. C. Deprá et al.
Given this scenario, boosted by the favorable market, the intensification of the
research resulted in important discoveries, which made it possible to open up alternative or additional biotechnological processes for the industrial manufacture of
natural food colorants with enhanced functionalities (Tuli et al. 2015).
Thus, microalgae have emerged as an attractive alternative, since they are
microorganisms capable of naturally synthesized pigments such as chlorophylls,
carotenoids, and phycobiliproteins that exhibit several health-relevant properties
besides colorant, such as anti-viral, antimicrobial, anti-inflammatory, antioxidant,
pro-vitamin A, immunomodulatory and anticancer activities (Viera et al. 2018). In
terms of microalgae-based pigments that reached the commercial level, β-carotene
from Dunaliella salina, astaxanthin from Haematococcus pluvialis and phycocyanin
from Arthrospira platensis are molecules already approved as food ingredients by
main world regulatory organizations (EC EFSA 1997; MHLW 1996; ANVISA 2018;
FDA 2019).
However, in spite of the perceived advantages, a number of techno-economic
barriers need to be overcome for the consolidating of microalgae-based processes on a
commercial scale. In order to understand this processes performance, comprehensive
analyses addressing environmental, economic and social indicators should be carried
out following a life cycle perspective (Gong and Bassi 2016).
In this sense, the objective of this chapter is to perform a comparative life cycle
assessment of the current production scenarios of synthetic and microalgae-based
pigments with a focus on the establishment of sustainable metrics.
15.2 Synthetic Pigments
Chemical synthesis of pigments was developed by three teams independently in
the year 1950, being considered a milestone in the research of pigments (Karrer
and Eugster 1950; Inhoffen et al. 1950, Milas et al. 1950). In 1976, more than 90
naturally occurring pigments were synthesized based on this early work, through
the principle of coupling appropriate end groups to a central building block. During
this time some methods of chemical synthesis have been successfully developed to
obtain pigments and they have since been used repeatedly (Britton et al. 1996). Two
examples of these methods are illustrated in Figs. 15.1 and 15.2.
The first scaled up method developed by Hoffman-La Roche was the Roche
synthesis in 1954. With a yield of 60%, this method was based on the Grignard
reaction (enol ether condensation) and follows the C 19 + C 2 + C 19 synthesis principle (Fig. 15.1) (Ribeiro et al. 2011). By the glycidic ester synthesis, the ß-ionone is
lengthened to ß-C14-aldehyde. Through an alkali treatment, a CH 2 -group link to the
side chain of this aldehyde, thus undoing the double-bonded conjugate system of the
ring. Thus, the ß-C14-aldehyde is transformed into its acetal for chain lengthening,
being condensed with vinyl ether in the catalytic presence of an acid. Subsequent
hydrolysis gives the crystalline ß-C16-aldehyde. By a similar process, the β-C16
is converted with propenyl ether to the crystalline ß-C19-aldehyde. Through the