High-throughput screening of aqueous two-phase systems for polyphenol extraction from A. nodosum: a green chemistry approach
Brown macroalgae are an attractive third-generation feedstock of natural products, in order to design green chemistry-compliant processes and reduce the use of organic solvents in bioactive product extraction, aqueous two-phase systems (ATPS) was applied. This research aimed to develop a high-throughput screening (HTS) to recover polyphenols from Ascophyllum nodosum using ATPS. In total, 384 different 2-phase systems were assessed using an automated liquid-handling system to evaluate polyphenol recovery using a model system of phloroglucinol to establish an optimal 2-phase system for polyphenol partitioning. Various ratios of PEG:potassium phosphate solutions were explored to evaluate partitioning of polyphenols via a scale-down approach. Scale-down selected system showed a recovery of phloroglucinol of 62.9±12.0%, this system was used for scale-up trials. Scale-up studies confirmed that the HTS method was able to recover polyphenols with a 54.8±14.2% in the phloroglucinol model system. When the optimised ATPS system was tested with a polyphenol extract, 93.62±8.24% recovery was observed. When ATPS was applied to a fucoidan and alginate biorefinery residue, 88.40±4.59% polyphenol was recovered. These findings confirm that ATPS is a valuable addition to the bioprocess toolkit for sustainable extraction of natural products from macroalgae in a multiproduct biorefinery approach.