Valorization of Algal Spent Biomass into Valuable Biochemicals and Energy Resource [Book Chapter]
VASANTHAKUMAR (S), GREESHMA (K), ARUMUGAM (M)
Algal Biorefineries and the Circular Bioeconomy
Algae are the largest primary producers in the world and are found in every ecological niche conceivable. They are production systems of numerous bioactive compounds that are gaining more interest since they can be utilized in several ways. After large-scale production of primary compounds of interest, the residual biomass left is rich in many value-added compounds, which are mostly underutilized or unmapped. Algae production facilities should run in a closed loop biorefinery approach in order to produce the maximum number of possible products, which have a key role in launching sustainable bioprocess technologies, industrial translations, and a circular economy. Algae are an untapped source for valuable biochemical and energy resources. This effective biomass exploitation will lead to sustainable bio-economy advancement. Although there are few reports suggesting this practice, its complete usage within biorefinery context is still enigmatic. Residual algal biomass is left after major product extraction, with many value-added compounds with potential application in pharmaceutical, nutraceutical, cosmeceutical, energy, food, and agriculture industries. The targeted utilization of spent biomass in various bio-processes will result in efficient carbon utilization and therefore maximum yield of quality products. Valorization of this spent biomass in the field of biopolymer industries can address the environmental issues concerned with plastic. In this chapter, we discuss the cost-effective optimization of different extraction methods, valorization of each residual biomass fraction obtained after extraction, and the composition and different industrial utilities for the multiple bio-based products.