An extraction protocol was developed to maximize the amount of extracts obtained from three brown seaweeds, Lessonia nigrescens (in two stages of development), Macrocystis pyrifera, and Durvillaea antarctica, and to evaluate them as natural inhibitors of the angiotensin I-converting enzyme (ACE). Two extraction methods were used, an enzymatic method (cellulase and α-amylase) and a conventional method (maceration). The extracts were analyzed to determine the extraction yield (%), the total phenolic and carbohydrate concentrations, and the ACE inhibition. Juvenile L. nigrescens extracts obtained by α-amylase exhibited the highest extraction yield (37.72±4.13 %), the highest ACE inhibition (95.61±0.33 %), and the lowest IC 50 (10.10± 1.55 μg PGE mg −1 seaweed) among the studied extracts. Extraction by maceration produced extracts with chemical characteristics that were less favorable for inhibiting ACE than the enzymatic extraction. The presence of phlorotannins and carbohydrates in these brown seaweeds after enzymatic extraction could be responsible for the superior ACE inhibitory activity of the extracts. Thus, these molecules could be considered as potential phytopharmaceuticals for the development of new ACE inhibitors.
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.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.