Macroalgal biorefinery concepts for the circular bioeconomy: A review on biotechnological developments and future perspectives

The imminent need for transition to a circular bioeconomy, based on the valorisation of renewable biomass feedstocks, will ameliorate global challenges induced by climate change, environmental pollution and population growth. A reduced reliance on depleting fossil fuel resources and ensured production of eco-friendly and costeffective bioproducts and biofuels, requires the development of sustainable biorefinery processes, with many utilising macroalgae as feedstock, showing promising and viable prospects. Nonetheless, macroalgal biorefinery research is still in its infancy compared to lignocellulosic biorefineries that utilise terrestrial plants. This article presents a review on the latest scientific literature associated with the development and status of macroalgal biorefineries, and how bioproducts generated from these bioprocesses have contributed towards the bioeconomy. The fundamental need to understand how the unique biochemical composition of macroalgae fit within a biorefinery concept are explained, alongside discussion of the novel biotechnologies that have been applied. In order to comprehend the increasing significance of this exciting field, the review will also provide insight, for the first time, on the current global funding and intellectual property landscape related to macroalgae and their implementation across the entire biorefinery concept. Imperative areas for further research and development, to bridge the gap between fundamental bioscience in the laboratory and the successful application of compatible biotechnologies at a commercial scale, to boost the macroalgae industry are also covered.