Methods in Molecular Biology (2020) 1980: 71–80
DOI 10.1007/7651_2018_128
© Springer Science+Business Media New York 2018
Published online: 27 March 2018
Determining Inorganic and Organic Nitrogen
Jaana Koistinen, Mervi Sjo ¨ blom, and Kristian Spilling
Abstract
Nitrogen (N) is one of the key nutrients for algal growth and is an integral part of many cellular
components, for example in proteins. Being able to determine the inorganic and organic pools of N is
consequently critical for algal cultivation. In this chapter we present the methods we use for determining
dissolved inorganic nitrogen (DIN), dissolved organic nitrogen (DON), and particulate organic nitrogen
(PON). The methods presented here for DIN rely on colorimetric methods and those of DON and PON
on filtration and high temperature catalytic oxidation.
Keywords Ammonium, Dissolved organic nitrogen, Nitrate, Nutrient uptake, Particulate organic
nitrogen
1 Introduction
Nitrogen (N) is one of the key nutrients for algal growth and is an
integral part of many cellular components, for example in proteins.
There is plenty of nitrogen around but most of it is in the form of
nitrogen gas—N 2 (~78% of the atmosphere is nitrogen gas). This is
not biologically available with the exception of a few nitrogen fixers
that can use N 2 gas, for example some cyanobacteria. The basic
inorganic form of nitrogen that is used for algal growth is nitrate
(NO 3
À
), nitrite (NO 2
À ), and ammonium (NH 4
þ
). In addition, some
organic forms of nitrogen can be used by some algae, but large pools
of dissolved organic nitrogen can yield high biomass of bacteria.
When cultivating algae it is therefore important to have some
idea of the availability of inorganic nitrogen as this is a prerequisite for
growth. Inorganic nitrogen is taken up and forms organic forms (e.g.,
protein), and being able to determine organic forms (particulate
and dissolved forms) might be important for any downstream processing of the biomass and cultivation water after biomass removal.
In this chapter we present the methods we use for determining
dissolved inorganic, dissolved organic, and particulate organic
forms of N. The dissolved inorganic nitrogen (DIN; nitrite, nitrate,
The original version of this chapter was revised. The correction to this chapter is available at https://doi.org/10.
1007/7651_2019_252
71
DOI 10.1007/7651_2018_128
© Springer Science+Business Media New York 2018
Published online: 27 March 2018
Determining Inorganic and Organic Nitrogen
Jaana Koistinen, Mervi Sjo ¨ blom, and Kristian Spilling
Abstract
Nitrogen (N) is one of the key nutrients for algal growth and is an integral part of many cellular
components, for example in proteins. Being able to determine the inorganic and organic pools of N is
consequently critical for algal cultivation. In this chapter we present the methods we use for determining
dissolved inorganic nitrogen (DIN), dissolved organic nitrogen (DON), and particulate organic nitrogen
(PON). The methods presented here for DIN rely on colorimetric methods and those of DON and PON
on filtration and high temperature catalytic oxidation.
Keywords Ammonium, Dissolved organic nitrogen, Nitrate, Nutrient uptake, Particulate organic
nitrogen
1 Introduction
Nitrogen (N) is one of the key nutrients for algal growth and is an
integral part of many cellular components, for example in proteins.
There is plenty of nitrogen around but most of it is in the form of
nitrogen gas—N 2 (~78% of the atmosphere is nitrogen gas). This is
not biologically available with the exception of a few nitrogen fixers
that can use N 2 gas, for example some cyanobacteria. The basic
inorganic form of nitrogen that is used for algal growth is nitrate
(NO 3
À
), nitrite (NO 2
À ), and ammonium (NH 4
þ
). In addition, some
organic forms of nitrogen can be used by some algae, but large pools
of dissolved organic nitrogen can yield high biomass of bacteria.
When cultivating algae it is therefore important to have some
idea of the availability of inorganic nitrogen as this is a prerequisite for
growth. Inorganic nitrogen is taken up and forms organic forms (e.g.,
protein), and being able to determine organic forms (particulate
and dissolved forms) might be important for any downstream processing of the biomass and cultivation water after biomass removal.
In this chapter we present the methods we use for determining
dissolved inorganic, dissolved organic, and particulate organic
forms of N. The dissolved inorganic nitrogen (DIN; nitrite, nitrate,
The original version of this chapter was revised. The correction to this chapter is available at https://doi.org/10.
1007/7651_2019_252
71