15
Genetic Engineering Approaches for
the Exploitation of Marine Algae as
Potential Sources of Organic and
Inorganic Biofuels
Maria Gloria Esquível,
1,
* Julia Marín-Navarro,
2
Teresa S. Pinto
1
and
Joaquín Moreno
2
Introduction
Marine algae include cyanobacteria, eukaryotic microalgae, and seaweed. They are critical to the health
of our planet and are dominant in the oceans, which produce approximately half of the oxygen that we
breathe (Brodie et al. 2017). Unicellular algae (which sometimes associate in colonies) are known as
microalgae. Examples of prokaryotic microalgae are cyanobacteria (Cyanophyceae), and of eukaryotic
microalgae are green algae (Chlorophyceae) and diatoms (Mediophyceae and Bacillariophyceae). Due
to the favourable natural features of microalgae, such as fast growth and high photosynthetic efficiency
(compared to higher plants), these organisms appear as ideal for high biomass production. Algal biomass
is a potential source of feed/foodstuff, added-value products, or biofuel. The latter possibility is especially
attractive because algal metabolism naturally produces substances that can be directly used as (or easily
converted to) fuel. Among these are hydrogen (Melis et al. 2000; Ghirardi et al. 2007; Esquível et al.
2011), alcohols (Spolaore et al. 2006), and lipids (Mata et al. 2010). Furthermore, biofuels can be produced
simultaneously with value-added by-products for the chemical industry and human health, including
oils (e.g., triglycerides), polysaccharides (e.g., alginate, agar), and pigments (e.g., phycobiliproteins,
carotenoids). Current protocols allow the genetic manipulation of the algal strains to redesign the cellular
1
Landscape, Environment, Agriculture and Food (LEAF), Instituto Superior de Agronomia (ISA), Universidade de Lisboa,
Lisbon, Portugal.
Email: tpinto@isa.utl.pt
2
Dept. Biochemistry & Molecular Biology, Faculty of Biology, University of Valencia C Dr. Moliner 50, Burjassot E-46100
(Spain).
Emails: juvicma@uv.es; joaquin.moreno@uv.es
* Corresponding author: gesquivel@isa.utl.pt
Genetic Engineering Approaches for
the Exploitation of Marine Algae as
Potential Sources of Organic and
Inorganic Biofuels
Maria Gloria Esquível,
1,
* Julia Marín-Navarro,
2
Teresa S. Pinto
1
and
Joaquín Moreno
2
Introduction
Marine algae include cyanobacteria, eukaryotic microalgae, and seaweed. They are critical to the health
of our planet and are dominant in the oceans, which produce approximately half of the oxygen that we
breathe (Brodie et al. 2017). Unicellular algae (which sometimes associate in colonies) are known as
microalgae. Examples of prokaryotic microalgae are cyanobacteria (Cyanophyceae), and of eukaryotic
microalgae are green algae (Chlorophyceae) and diatoms (Mediophyceae and Bacillariophyceae). Due
to the favourable natural features of microalgae, such as fast growth and high photosynthetic efficiency
(compared to higher plants), these organisms appear as ideal for high biomass production. Algal biomass
is a potential source of feed/foodstuff, added-value products, or biofuel. The latter possibility is especially
attractive because algal metabolism naturally produces substances that can be directly used as (or easily
converted to) fuel. Among these are hydrogen (Melis et al. 2000; Ghirardi et al. 2007; Esquível et al.
2011), alcohols (Spolaore et al. 2006), and lipids (Mata et al. 2010). Furthermore, biofuels can be produced
simultaneously with value-added by-products for the chemical industry and human health, including
oils (e.g., triglycerides), polysaccharides (e.g., alginate, agar), and pigments (e.g., phycobiliproteins,
carotenoids). Current protocols allow the genetic manipulation of the algal strains to redesign the cellular
1
Landscape, Environment, Agriculture and Food (LEAF), Instituto Superior de Agronomia (ISA), Universidade de Lisboa,
Lisbon, Portugal.
Email: tpinto@isa.utl.pt
2
Dept. Biochemistry & Molecular Biology, Faculty of Biology, University of Valencia C Dr. Moliner 50, Burjassot E-46100
(Spain).
Emails: juvicma@uv.es; joaquin.moreno@uv.es
* Corresponding author: gesquivel@isa.utl.pt