4
Microalgal Biomass Production
Rathinam Raja,
1
Hemaiswarya Shanmugam,
2,
* Ramanujam Ravikumar
3
and Isabel S. Carvalho
1
Introduction
Microalgae are unicellular and the most abundant primary producers found in all the aquatic systems such
as, freshwater, seawater, hypersaline lakes, and even in deserts and arctic ecosystems. Sub-divided into
eukaryotic and prokaryotic algae, eukaryotes possess defined cell organelles such as nuclei, chloroplasts,
mitochondria whereas prokaryotes (cyanobacteria or blue-green) are primitive, possessing the simpler
cellular structure of bacteria. These algae convert light energy and carbon dioxide (CO 2 ) into biomass
such as carbohydrates (Park et al. 2011), proteins (Becker 2007), and lipids (Harwood and Guschina
2009) through a process called, photosynthesis. Their photosynthetic mechanism is similar to land-based
plants, but due to a simple cellular structure, and being submerged in an aqueous environment where they
have efficient to access water, CO 2 and other nutrients, they are more efficient in converting solar energy
into biomass. Many microalgae species are able to switch from phototrophic to heterotrophic growth
conditions. As heterotrophs, the algae rely on glucose or other carbon sources for carbon metabolism and
energy and some algae can grow mixotrophically. Microalgae can also grow in extreme environments;
it could also be produced on agricultural and non-agricultural lands. Fresh, brackish, saline, wastewater,
municipal sewage, and industrial effluents can be used to cultivate microalgae (Raja et al. 2004). Some of
the important updates on the biomass of algae will be elaborated in the upcoming sessions.
Microalgae
Natural food production is directly related to the growth of microscopic plants called algae (Aaron et
al. 2011). They have many inherent advantages, some of them are: higher productivity (biomass) in few
days, easily adaptable to new environments and high-lipid content, being a fundamental edge. Algae are
cultivated not only as a food source but also for fuel and is unlikely to interfere with food production. It
is widely believed (though research has to confirm) that the use of algal-based fuel would result in a tiny
fraction of the net greenhouse gases. Also, scaling up algae could lead to yields of other commercially
1
Food Science Laboratory, Centre for Mediterranean Bioresources and Food, FCT, University of Algarve, Campus de
Gambelas, Faro 8005-139, Portugal.
2
AUKBC Research Centre, Anna University, MIT Campus, Chrompet, Chennai-600 044, Tamil Nadu, India.
3
Aquatic Energy LLC, One Lakeshore Drive, Lake Charles, Louisiana 70629, USA.
* Corresponding author: iswaryahema@gmail.com
Microalgal Biomass Production
Rathinam Raja,
1
Hemaiswarya Shanmugam,
2,
* Ramanujam Ravikumar
3
and Isabel S. Carvalho
1
Introduction
Microalgae are unicellular and the most abundant primary producers found in all the aquatic systems such
as, freshwater, seawater, hypersaline lakes, and even in deserts and arctic ecosystems. Sub-divided into
eukaryotic and prokaryotic algae, eukaryotes possess defined cell organelles such as nuclei, chloroplasts,
mitochondria whereas prokaryotes (cyanobacteria or blue-green) are primitive, possessing the simpler
cellular structure of bacteria. These algae convert light energy and carbon dioxide (CO 2 ) into biomass
such as carbohydrates (Park et al. 2011), proteins (Becker 2007), and lipids (Harwood and Guschina
2009) through a process called, photosynthesis. Their photosynthetic mechanism is similar to land-based
plants, but due to a simple cellular structure, and being submerged in an aqueous environment where they
have efficient to access water, CO 2 and other nutrients, they are more efficient in converting solar energy
into biomass. Many microalgae species are able to switch from phototrophic to heterotrophic growth
conditions. As heterotrophs, the algae rely on glucose or other carbon sources for carbon metabolism and
energy and some algae can grow mixotrophically. Microalgae can also grow in extreme environments;
it could also be produced on agricultural and non-agricultural lands. Fresh, brackish, saline, wastewater,
municipal sewage, and industrial effluents can be used to cultivate microalgae (Raja et al. 2004). Some of
the important updates on the biomass of algae will be elaborated in the upcoming sessions.
Microalgae
Natural food production is directly related to the growth of microscopic plants called algae (Aaron et
al. 2011). They have many inherent advantages, some of them are: higher productivity (biomass) in few
days, easily adaptable to new environments and high-lipid content, being a fundamental edge. Algae are
cultivated not only as a food source but also for fuel and is unlikely to interfere with food production. It
is widely believed (though research has to confirm) that the use of algal-based fuel would result in a tiny
fraction of the net greenhouse gases. Also, scaling up algae could lead to yields of other commercially
1
Food Science Laboratory, Centre for Mediterranean Bioresources and Food, FCT, University of Algarve, Campus de
Gambelas, Faro 8005-139, Portugal.
2
AUKBC Research Centre, Anna University, MIT Campus, Chrompet, Chennai-600 044, Tamil Nadu, India.
3
Aquatic Energy LLC, One Lakeshore Drive, Lake Charles, Louisiana 70629, USA.
* Corresponding author: iswaryahema@gmail.com