Research progress on optimization of light conditions during Chlorella culture

Abstract

With the role of Chlorella in bioenergy, big health, sewage treatment and carbon emission reduction, Chlorella attracts more and more attention. Chlorella is significantly affected by light during growth. For a long time, in order to improve the biomass, active substance production, and the application in environmental protection, the effect of light on the algae has been deeply studied. Literature research shows that the light intensity around 6000 lx can provide sufficient light energy for Chlorella, and its net photosynthetic oxygen release rate increases rapidly with the increase of light intensity, but is inhibited beyond the light saturation;although it is not conducive to photosynthesis and rapid growth under low light, it is conducive to the synthesis and accumulation of EPA and the removal of nitrogen and phosphorus by the symbiotic system of bacteria and algae. Different color light has different effects on promoting the growth of Chlorella algae and improving the production of active substances.14:10h is more suitable for the photosynthesis in Chlorella and algae; high frequency light can reduce the photoinhibition effect. Due to the different gene expression levels at different growth stages, corresponding light measures should be taken according to its adaptive differences. Based on the above views, the future light research of Chlorella should be conducted on the adaptive light device, automatic corresponding changes of light during the whole life cycle of chlorella and the characteristic light required by the characteristic active substances.