Regulating the growth and chemical compositions of a freshwater microalga Chlorella sorokiniana by adding myo-inositol to culture media

The aim of this work was to investigate the effects of myo-inositol (MI) on growth, photosynthetic activity, and chemical compositions of Chlorella sorokiniana. Results showed that a maximum value of cell density was obtained when this alga was cultivated in BG11 media with 1000 mg L-1 MI, which was 1.37 times greater than that in the controls. Moreover, it was observed that MI had a negative effect on algal photosynthetic activity, which could be alleviated by regulating the contents of chemical compositions, such as chlorophyll a (Chl a). In the BG11 media with MI, contents of Chl a in the algal cells were in the range of 0.30?0.35 ?g 10-6 cells, which were about 1.75 times greater than that in the controls during microalgae cultivation. The accumulated Chl a would be used to capture and deliver more photons during algal photosynthesis. In addition, contents of lipids, carbohydrates, and proteins varied with the changes in MI concentrations. Thus, it is concluded that MI could promote the algal growth and play an important role in regulating the biochemical compositions in algal cells. These data would provide basic theory and technical support for large-scale cultivation and biomass production of microalgae by adding MI to culture media.

Automated summary

The study showed that myo-inositol (MI) can promote the growth and regulate the biochemical compositions of Chlorella sorokiniana, while having a negative impact on photosynthetic activity. Adjusting the MI concentration can affect the content of chlorophyll a and enhance algal photosynthesis.