Total percentage of lipids from dry weight increased from 21% during logarithmic growth phase to 31% in stationary growth phase.
Under high light - Percentage of TAG from total lipid increase from 7-10% in logarithmic growth phase to 47% during stationary growth phase (100 μmol photons m2 s-1).
Increase of total lipid content by 1000% under high UV-B treatment.
Cell cycle inhibition
Increased in natural lipid abundance occurred faster and to a higher extent than when starving the cells to nitrogen.
Using old sterile media of Nitzschia sp. With sufficient nitrogen source
80 μmol photons m-2 s-1, 30 °C, 1.5% CO2 bublling
Increase of 142% in lipid content after 1 day, and 542% of the lipid content in 4 days.
Other environmental/chemical manipulations
Addition of 0.88 mM sodium tungstate (without Molibdinum)
ASW based F/2, 300 μmol photons m2 s-1 white fluorescent, continuous light, 18 °C
TFA increased by 67%, from 2.39 to 3.99 pg cell-1 Quantum requirement for incorporating FA, increased by 162%.
Addition of 0.88 mM sodium tungstate (without Molibdinum)
ASW based F/2, 200 μmol photons m2 s-1 white LED, continuous light, 18 °C
TFA increased by 14%, from 2.9 to 3.3 pg cell-1 Quantum requirement for incorporating FA did not change.
Nitzschia laevis (UTEX 2047)
Modified Lewin’s medium, NaCl was adjusted to 5, 10, 20, and 30 g L-1.
From 0.58 at 10 g NaCl L-1
to 0.41 at 40 g NaCl L-1
Percentage of TAGs from total lipids increased from 37% to 69% when reducing NaCl from 30 g L-1 to 10 g L-1.
Percentage of natural lipids from total lipids was increased from 43% to 79% when reducing NaCl from 30 g L-1 to 10 g L-1.
Transformants showed 2.4- and 3.3-fold higher lipid content than wild-type during exponential growth, and 4.1- and 3.2-fold higher lipid content than wild-type after 40 h of silicon starvation.
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