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14 Cellulose
in aquatic organisms compared to terrestrial sources such as wood. This alters the
extraction process in ways we shall explore within this chapter.
As the world population continues to increase annually, more land space is
required for housing, animal grazing and growing of plants. It becomes important to
understand the role the aquatic environment plays in replacing or augmenting the cellulose from terrestrial plants. Cultivation and harvesting of aquatic-based cellulosic
biomass take a different process compared to that of terrestrial plants. The fact that
the land requirement is omitted means the production of aquatic-based cellulose does
not interfere with the occupation of land by humans for habitation, animal grazing
and crop production.
This chapter therefore explores the economic impact in terms of availability of
feedstock and applications in different industries. The environment impact is also
assessed through reviewing the extraction processes and occurrence in nature. Additionally, the chapter also explores the chemistry of cellulose and peculiar characteristics of cellulose from aquatic sources. This is aimed to guide and inform exploration
of cellulose production from aquatic sources and encourage the conservation of such
resources as well as further research in the area.
14.2 Occurrence in Nature
Cellulose is the most abundant polymer on earth. It is present in all plants and algae
as a structural polymer and in bacteria as protection against UV radiation and harsh
chemicals. It is indigestible by humans and however can be digested by ruminant
animals and some bacteria. Within the aquatic environment, aquatic plants and algae
serve as the sources of cellulose. The rate of generation if cellulosic biomass by
aquatic plants and algae is much faster than that it terrestrial plants. Non-competition
with space used for cultivation of edible crops and for human habitation and the
bioremediation properties of some aquatic plants and algae make aquatic plants and
algae serve as particularly appealing option for cellulose-based products.
Aquatic plants have the advantage over algae as a source of cellulose being freefloating plants. This makes their harvesting and cultivation much simpler and less
expensive. Aquatic plants which have drawn much interest over the years are Azolla,
duckweed and water hyacinth. Each one is of interest for different reasons, due to
either the resource potential or the adverse impact on human activity and the environment. The occurrence of these plants in nature is also affected by human activities such as introducing pollutants into the water. The environmental and economic
impact of these plants can therefore be controlled by understanding their resource
potential and growth parameters.
The Azolla plant makes an interesting source of cellulose because of the plant’s
remarkable ability to grow in wastewater. Azolla metabolizes contents of wastewater
such as nitrogen and phosphorus and produces metabolites for its growth and survival.
Metabolites include cellulose, hemicellulose, starch and lipids. Azolla grows well
in rural lagoons, rivers, ponds, irrigation channels, ditches and wetlands under a
14 Cellulose
in aquatic organisms compared to terrestrial sources such as wood. This alters the
extraction process in ways we shall explore within this chapter.
As the world population continues to increase annually, more land space is
required for housing, animal grazing and growing of plants. It becomes important to
understand the role the aquatic environment plays in replacing or augmenting the cellulose from terrestrial plants. Cultivation and harvesting of aquatic-based cellulosic
biomass take a different process compared to that of terrestrial plants. The fact that
the land requirement is omitted means the production of aquatic-based cellulose does
not interfere with the occupation of land by humans for habitation, animal grazing
and crop production.
This chapter therefore explores the economic impact in terms of availability of
feedstock and applications in different industries. The environment impact is also
assessed through reviewing the extraction processes and occurrence in nature. Additionally, the chapter also explores the chemistry of cellulose and peculiar characteristics of cellulose from aquatic sources. This is aimed to guide and inform exploration
of cellulose production from aquatic sources and encourage the conservation of such
resources as well as further research in the area.
14.2 Occurrence in Nature
Cellulose is the most abundant polymer on earth. It is present in all plants and algae
as a structural polymer and in bacteria as protection against UV radiation and harsh
chemicals. It is indigestible by humans and however can be digested by ruminant
animals and some bacteria. Within the aquatic environment, aquatic plants and algae
serve as the sources of cellulose. The rate of generation if cellulosic biomass by
aquatic plants and algae is much faster than that it terrestrial plants. Non-competition
with space used for cultivation of edible crops and for human habitation and the
bioremediation properties of some aquatic plants and algae make aquatic plants and
algae serve as particularly appealing option for cellulose-based products.
Aquatic plants have the advantage over algae as a source of cellulose being freefloating plants. This makes their harvesting and cultivation much simpler and less
expensive. Aquatic plants which have drawn much interest over the years are Azolla,
duckweed and water hyacinth. Each one is of interest for different reasons, due to
either the resource potential or the adverse impact on human activity and the environment. The occurrence of these plants in nature is also affected by human activities such as introducing pollutants into the water. The environmental and economic
impact of these plants can therefore be controlled by understanding their resource
potential and growth parameters.
The Azolla plant makes an interesting source of cellulose because of the plant’s
remarkable ability to grow in wastewater. Azolla metabolizes contents of wastewater
such as nitrogen and phosphorus and produces metabolites for its growth and survival.
Metabolites include cellulose, hemicellulose, starch and lipids. Azolla grows well
in rural lagoons, rivers, ponds, irrigation channels, ditches and wetlands under a