ABSTRACT
Microalgae have been a well-known dietary source for many years. Recently, they became popular again for their ability to produce valuable bio-based products of commercial value. The algal biomass and its products have a wide range of applications in feed markets, food, pharma and nutraceuticals, cosmetics, polymer and biofuel industries, etc. Due to the high product value, the demand for algal biomass is increasing. To meet the demand, research is already focusing on improving the algaculture productivity and the process viability. The traditional methods for enhancing algal biomass included process optimization and nutrient manipulation. Recent approaches to increase biomass production focused on addressing growth-related issues such as poor carbon fixation and improper light utilization. The approaches included improved cultivation systems and genetic engineering. Further, novel strategies that can bring improvement at the photosynthetic level are evolving. Techniques such as spectral shifting using luminescent molecules and photon up-conversion using an appropriate phosphor system have increased the biomass yield in microalgae such as Chlorella. Similarly, modifying their photosynthetic antenna size through genome engineering or reactive species inducers to cause intracellular stress can substantially improve the biomass yield. In this chapter, we will focus on the above techniques and other recent developments for enhancing microalgal productivity.
