Enhanced β-carotene production in Dunaliella salina under relative high flashing light

The flashing light, an artificial illumination, has been considered as one of the most promising light regimes for microalgae to produce high-value biochemicals. However, the effect of flashing light on the β-carotene accumulation in the green microalga Dunaliella salina and the corresponding photosynthetic response was unclear. In this study, the changes of biomass accumulation, β-carotene content, and photosynthetic response under different flashing light regimes were monitored in Dunaliella salina. The results showed that the cells illuminated by flashing light have higher biomass and β-carotene productivity than continuous light with the same amount of photons emitted. Moreover, we found that the enhanced β-carotene yield induced by flashing light is positively correlated to the increase of the electron transport rate and reactive oxygen species content in Dunaliella salina. This study is potentially useful for engineering of microalgae bioreactors equipped with the optimal light frequencies of flashing light to increase biomass production and the yield of the valuable metabolites of interest in microalgae.