Green and integrated processing approaches for the recovery of high-value compounds from brown seaweeds

The rapidly increasing interest in utilizing seaweeds as sustainable raw material from which multiple high-value bioactive compounds can be recovered, has necessitated the development of new processing methods to achieve this. Brown seaweeds contain a range of bioactive compounds that are of commercial interest, including hydrocolloid and non-hydrocolloid polysaccharides, antioxidant polyphenols and unique pigments. Traditional polysaccharide extraction from brown seaweeds has relied on methods that require harsh chemical processing and sometimes also large amounts of energy and organic solvents. Commercial operation requires high recovery of the targeted compounds on the one hand, but simultaneously also the preservation of biological activity of the products on the other, an objective that is difficult to achieve using conventional methods. In order to address this shortcoming and to move toward more environmentally friendly processing in general, several greener extraction methods are being developed which have lower environmental footprint and sometimes also greater process efficiency, including enzymatic, sub and supercritical fluid, ultrasonic and microwave extraction techniques. This chapter explores these extraction techniques within the context of particularly brown seaweeds and provides an overview of potential advantages compared to conventional technologies. The work further elucidates how certain physiological characteristics of brown seaweeds can impact the processing thereof and looks toward possible future developments within the field of brown seaweed processing.