Biotechnological valorization of algal biomass: an overview

Abstract

Algal biomass has significant advantages over terrestrial plants in terms of CO 2 sequestration, biomass productivity, wastewater treatment along with multiple biobased products synthesis. Metabolic versatility and high carbohydrate content of microalgal biomass act as a potential alternative feedstock to fossil resources and contribute towards the biobased economy growth. Effective biomass utilization would play a key role to establish sustainable bioprocess development and technology translation to the industrial community. In this framework, the present review discusses the renewable resource potential of algal biomass and its complete utilization for multiple biobased products synthesis in a closed-loop biorefinery approach. Various methods are discussed to obtain high biomass growth and pretreatments to obtain the maximum sugars solubilization. Further, combined bioprocesses were discussed for the production of biohydrogen, biomethane, bioethanol, short-chain fatty acids (SCFA), medium-chain fatty acids (MCFA), and biopolymers in a closed-loop approach.

Algae-Based Biopolymers for Batteries and Biofuel Applications in Comparison with Bacterial Biopolymers—A Review

“…This makes producing biofuel from algal biomass commercially challenging and suggests combining biofuel production with the extraction of high-value components from algae, such as therapeutics, nutraceuticals, and cosmetics [ 41 , 180 ]. On the other hand, waste-streams can be better managed if they are used as feedstock for algal growth, thereby using a waste-as-a-value approach that reduces the overall costs for the received algal products [ 181 , 182 ]. Furthermore, microalgal biomass can be grown on non-arable land and shows higher productivity of usable biomass than terrestrial plants, making algae advantageous for biofuel production [ 182 ].…”

“…On the other hand, waste-streams can be better managed if they are used as feedstock for algal growth, thereby using a waste-as-a-value approach that reduces the overall costs for the received algal products [ 181 , 182 ]. Furthermore, microalgal biomass can be grown on non-arable land and shows higher productivity of usable biomass than terrestrial plants, making algae advantageous for biofuel production [ 182 ].…”

Bioelectrochemical system-mediated waste valorization

“…Wastewater resource recovery is not a novel approach; it was successfully applied in several European countries before establishing wastewater treatment facilities [11]. Several studies have successfully established physical, mechanical, biological, and hybrid physical and chemical treatment methods to valorize the waste water's high nutrient account [12]. The biological nutrient removal approach is cost-effective and versatile compared to other treatment methods [13].…”

Cultivation of Anabena variabilis, Synechococcus elongatus, Spirulina platensis for the production of C-Phycocyanin, C-Phycoerythrin and Thalassiosira, Skeletonema, Chaetoceros for fucoxanthin

“…Some of the species exhibited the highest bactericidal activities against Grampositive bacteria while others exhibit the highest bactericidal activity against Gram-negative bacteria. Microalgae possess enormous potentials and are great reservoirs of an array of bioactive compounds [34,35], yet the studies are limited, and more explorations are indeed essential for elaboration of their mechanisms leading to enhanced commercial utility.…”