Current status and trends in extraction of bioactives from brown macroalgae using supercritical CO2 and subcritical water

Abstract

Bioactive compounds from brown seaweeds, such as polysaccharides, phenolics and pigments, have shown a range of health‐promoting properties that can be implemented in products like functional foods, cosmetics and medicine. Extraction is therefore crucial in recovering these bioactive compounds, but conventional methods today need to be more sustainable and efficient. In this review, the extraction of brown seaweeds using supercritical carbon dioxide (SCCO2) and subcritical water (SCW) is discussed comprehensively. Previous studies have shown that these two extraction technologies enhance the overall extraction yield of brown seaweed bioactive compounds when process parameters are optimised. These technologies have also been combined, either together or with other extraction methods, to improve overall extraction yield. Although this review shows the research progress of these technologies for brown seaweeds, scale‐up operations are still challenging owing to a variety of factors. Further research should focus on optimisation such that scale‐up is less difficult. With the knowledge presented in this review and with further work, these eco‐friendly extraction technologies could be commercialised within the seaweed industry. © 2022 The Authors. Journal of Chemical Technology and Biotechnology published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry (SCI).