Enzyme-assisted extraction of proteins from the seaweeds Macrocystis pyrifera and Chondracanthus chamissoi: characterization of the extracts and their bioactive potential

Seaweeds have great potential as raw material for protein-based functional ingredients due to their high protein content; however, their complex polysaccharide matrix could hinder protein extraction. In this work, protein extracts from the brown seaweed Macrocystis pyrifera and the red seaweed Chondracanthus chamissoi were obtained by optimization of an enzyme-assisted extraction using cellulase to enhance the protein extraction yields. The comparison of protein content obtained by enzymatic and non-enzymatic methods suggests that the disruption of the cellulase-sensitive carbohydrate matrix increases protein content on the extract. The protein extraction yields were 74.6% for M. pyrifera (18h, 1/10 enzyme/seaweed ratio) and 36.1% for C. chamissoi (12h, 1/10 enzyme/seaweed ratio). Both protein extracts showed antioxidant activity and M. pyrifera protein extract showed a potential antihypertensive activity. These results establish a firm basis for further studies on seaweed protein extracts as potential functional ingredients, or towards the production of bioactive peptides through a straightforward, and environmentally sustainable methodology.