Green technology in green macroalgal biorefineries

Abstract

Marine biorefineries, based on macroalgal (seaweed) feedstocks, could provide sustainable alternative sources of food, energy, and materials. Green macroalgae, with their unique chemical composition, can contribute to marine biorefinery systems associated with a wide range of potential products. This review discusses the challenge of developing industrially relevant and environmentally-friendly green seaweed biorefineries. First, we review potential products from green seaweeds and their co-production, the key element in an integrated biorefinery. Second, we discuss large-scale cultivation, hydrothermal treatments, fermentation, anaerobic digestion, and emerging green solvents, pulsed electric field, microwave, and ultrasound processing technologies. Finally, we analyse the main polysaccharides in green seaweeds: sulfated polysaccharides, starch, and cellulose, as products of a cascading biorefinery, with emphasis on applications and technological challenges. We provide a comprehensive state-of-the-art review of green seaweed as feedstock for the biorefinery, analysing opportunities and challenges in the field.

Trends in Seaweed Extract Based Biostimulants: Manufacturing Process and Beneficial Effect on Soil-Plant Systems

“…Likewise, bio-refinery based on seaweed have also been discussed by several authors. For instance, Zollman et al [108] proposed a concept for a seaweed bio-refinery based on tailored cascade process (horizontal and vertical), that exploit the properties of each fraction as to generate various products, including plant biostimulants, human and animal food, and biofuel. Those authors also insisted on the necessity of offshore cultivation through using methodologies that does not require nutrient supplementation, which should alleviate labor and energy inputs.…”

Seaweeds as nutraceuticals for health and nutrition

“…With the development of mass food manufacturing in the early 1900s, seaweed components were harnessed industrially. Hydrocolloids, such as alginate, carrageenan and agar, are still the most commonly used components because of their gelling properties in foods, pharmaceutical and biotechnological applications (Rhein-Knudsen et al 2015;Zollman 2019). The suitability of seaweed for bio-diesel production has been explored for developing green fuel alternatives (Abomohra et al 2018;Chye et al 2018).…”

The Evolution Road of Seaweed Aquaculture: Cultivation Technologies and the Industry 4.0

“…In the nutraceutical, pharmaceutical and biotechnological industries, there are some applications to hydrocolloids, for instance alginate, carrageenan and agar are used due to their gelling features [ 53 , 54 ]. However, other minor components of the seaweeds, as will be presented later in this review, could be applied in high-value products, making seaweed aquaculture even more profitable for the seaweed producers [ 55 , 56 , 57 , 58 ].…”