7. Dry the filter overnight at 60
C.
8. Weigh the filter again and calculate the DW from the difference
in weight before and after filtration. Divide the DW by the
filtered volume to get DW/L.
9. Combust the filter, 450
C for 4 h, and weigh it again.
10. Calculate the ash weight (AW) from the difference between the
weight of the filter after combustion and before filtration.
11. Calculate the ash-free dry weight (AFDW) from the difference
between DW and AW (see Note 8).
4 Notes
1. A range of different cultivation media exists; the main component is a source of nitrogen (normally ammonium or nitrate),
phosphorus (orthophosphate), and trace elements like iron; see,
e.g., Harrison and Berges [4] for an overview. A good overall
fertilizer for agriculture can be used, but some species will
require special medium recipes to grow well. Testing different
growth media is important when setting up new cultures.
2. For example, extreme habitats such as rock pools along the coast
will be inhabited by species adapted to large fluctuations in
temperature and salinity, which are traits that could make them
suitable for cultivation.
3. It is critical to remove the pipette from the flame before pulling;
if not, the tip of the micropipette will close and cannot be used.
4. You would likely have sucked up other cells that you are not
interested in, and one or several washing steps might be needed
in order to isolate only the cell of interest.
5. Following the growth of the initial culture closely is recommended; then you will get a good overview of how long the
culture grows under the cultivation conditions that you use. The
main thing is to reinoculate and start the culture growing again
before it dies.
6. Going from small-scale cultures to large-scale cultivation imposes
challenges, for example, the surface area-to-volume ratio of the
culture typically decreases. With lower surface area-to-volume
ratio, it is important to keep track of how this affects the gas
exchange. Providing sufficient CO 2 (and stable pH) and removal
of excess O 2 are vital for keeping optimal conditions for algal
photosynthesis and growth. Also, the light penetration will most
likely be different due to the different surface area-to-volume
ratio. In a dense culture, light will not penetrate far, which can
be counteracted by increasing the surface area-to-volume ratio or
by increasing the turbulence in the cultivation. The latter will
38
Kristian Spilling
C.
8. Weigh the filter again and calculate the DW from the difference
in weight before and after filtration. Divide the DW by the
filtered volume to get DW/L.
9. Combust the filter, 450
C for 4 h, and weigh it again.
10. Calculate the ash weight (AW) from the difference between the
weight of the filter after combustion and before filtration.
11. Calculate the ash-free dry weight (AFDW) from the difference
between DW and AW (see Note 8).
4 Notes
1. A range of different cultivation media exists; the main component is a source of nitrogen (normally ammonium or nitrate),
phosphorus (orthophosphate), and trace elements like iron; see,
e.g., Harrison and Berges [4] for an overview. A good overall
fertilizer for agriculture can be used, but some species will
require special medium recipes to grow well. Testing different
growth media is important when setting up new cultures.
2. For example, extreme habitats such as rock pools along the coast
will be inhabited by species adapted to large fluctuations in
temperature and salinity, which are traits that could make them
suitable for cultivation.
3. It is critical to remove the pipette from the flame before pulling;
if not, the tip of the micropipette will close and cannot be used.
4. You would likely have sucked up other cells that you are not
interested in, and one or several washing steps might be needed
in order to isolate only the cell of interest.
5. Following the growth of the initial culture closely is recommended; then you will get a good overview of how long the
culture grows under the cultivation conditions that you use. The
main thing is to reinoculate and start the culture growing again
before it dies.
6. Going from small-scale cultures to large-scale cultivation imposes
challenges, for example, the surface area-to-volume ratio of the
culture typically decreases. With lower surface area-to-volume
ratio, it is important to keep track of how this affects the gas
exchange. Providing sufficient CO 2 (and stable pH) and removal
of excess O 2 are vital for keeping optimal conditions for algal
photosynthesis and growth. Also, the light penetration will most
likely be different due to the different surface area-to-volume
ratio. In a dense culture, light will not penetrate far, which can
be counteracted by increasing the surface area-to-volume ratio or
by increasing the turbulence in the cultivation. The latter will
38
Kristian Spilling