242
11 Enzymes
compound is referred to as trimethylamine oxide (TMAO) (Seibel and Walsh 2002).
Although not a polymer or an enzyme in itself, its unique interaction with proteins
is of much significance to better understanding, conserving and utilizing the aquatic
environment and the resources therein. Water molecules are much smaller than protein molecules such that they can penetrate into the protein structure at high pressure
and destabilize the protein (Yancey et al. 2014). In the absence of TMAO, the small
molecules will be pushed into the protein structure and cause disruption of the protein tertiary and secondary structure thus preventing it from functioning, eventually
resulting in the death of the organism.
Although the precise mechanism of action is yet to be uncovered, it is seen in
higher concentration in the organisms which live in these deep waters compared to
those in the lower depths, and hence, it is attributed to their ability to survive at
the high pressures which exist in the deep sea. TMAO is also attributed with the
resistance of the enzymes in the fish to urea and also preventing the freezing of the
fish’s bodily fluid at the low temperatures in the deep sea (Seibel and Walsh 2002).
The compound which helps retain the enzyme structure and hence activity in fish
against the high pressure in the deep sea may, however, pose a health risk for humans.
TMAO has been associated with adverse cardiovascular events in humans (Velasquez
et al. 2016). However, more studies are required to confirm the mechanism by which
this occurs and other associated factors.
11.4 Availability of Raw Materials
In 2016, 89,000 tonnes of microalgae was farmed across 11 countries of the world,
88,600 tonnes of which was from China. These include species such as Haematococcus pluvialis, Nannochloropsis spp., Chlorella spp. and Spirulina spp., all being
farmed in large, medium and small scales. While macroalgae get a larger revenue
from their food sales, microalgae are mostly sold as high-value functional products.
Therefore, despite the lower annual tonnes produced, microalgae are valued at around
a billion USD annually, compared to that of macroalgae at 6 billion USD.
The protein content in macroalgae is comparable to those found in animal-based
proteins and is higher than those found in land plants such as soybean, wheat and
legumes. Algae yield around 2.5–7.5 tonnes per hectare annually, while microalgae
yield 4–15 tonnes per hectare annually. These yields are rather high compared to
the conventional plant-based proteins such as wheat, soybeans and legumes which
yield 1.1, 0.6–1.2 and 1–2 tonnes per hectare annually (van Krimpen et al. 2013).
Macroalgae and microalgae could contain similar or even more protein than terrestrial
plants typically used as protein source. Spirulina, microalga which have gained much
popularity as a nutrient source, could contain up to 63% protein per dry weight
(Tokusoglu and Unal 2003). The red algae species Porphyra tenera contains up to
47% protein per dry weight (Fleurence 1999).
11 Enzymes
compound is referred to as trimethylamine oxide (TMAO) (Seibel and Walsh 2002).
Although not a polymer or an enzyme in itself, its unique interaction with proteins
is of much significance to better understanding, conserving and utilizing the aquatic
environment and the resources therein. Water molecules are much smaller than protein molecules such that they can penetrate into the protein structure at high pressure
and destabilize the protein (Yancey et al. 2014). In the absence of TMAO, the small
molecules will be pushed into the protein structure and cause disruption of the protein tertiary and secondary structure thus preventing it from functioning, eventually
resulting in the death of the organism.
Although the precise mechanism of action is yet to be uncovered, it is seen in
higher concentration in the organisms which live in these deep waters compared to
those in the lower depths, and hence, it is attributed to their ability to survive at
the high pressures which exist in the deep sea. TMAO is also attributed with the
resistance of the enzymes in the fish to urea and also preventing the freezing of the
fish’s bodily fluid at the low temperatures in the deep sea (Seibel and Walsh 2002).
The compound which helps retain the enzyme structure and hence activity in fish
against the high pressure in the deep sea may, however, pose a health risk for humans.
TMAO has been associated with adverse cardiovascular events in humans (Velasquez
et al. 2016). However, more studies are required to confirm the mechanism by which
this occurs and other associated factors.
11.4 Availability of Raw Materials
In 2016, 89,000 tonnes of microalgae was farmed across 11 countries of the world,
88,600 tonnes of which was from China. These include species such as Haematococcus pluvialis, Nannochloropsis spp., Chlorella spp. and Spirulina spp., all being
farmed in large, medium and small scales. While macroalgae get a larger revenue
from their food sales, microalgae are mostly sold as high-value functional products.
Therefore, despite the lower annual tonnes produced, microalgae are valued at around
a billion USD annually, compared to that of macroalgae at 6 billion USD.
The protein content in macroalgae is comparable to those found in animal-based
proteins and is higher than those found in land plants such as soybean, wheat and
legumes. Algae yield around 2.5–7.5 tonnes per hectare annually, while microalgae
yield 4–15 tonnes per hectare annually. These yields are rather high compared to
the conventional plant-based proteins such as wheat, soybeans and legumes which
yield 1.1, 0.6–1.2 and 1–2 tonnes per hectare annually (van Krimpen et al. 2013).
Macroalgae and microalgae could contain similar or even more protein than terrestrial
plants typically used as protein source. Spirulina, microalga which have gained much
popularity as a nutrient source, could contain up to 63% protein per dry weight
(Tokusoglu and Unal 2003). The red algae species Porphyra tenera contains up to
47% protein per dry weight (Fleurence 1999).