Extraction and Purification of a Phycocolloid from Chaetomorpha aerea

Phycocolloids are gelling polysaccharides extracted from algae that have found applications as microbiological culture media, food thickener, and cosmetic rheological modifiers. The extensive use of algae species that have not yet been domesticated has led to overexploitation or supply shortages. Thus, extending the library of phycocolloids would permit to support the industrial changes toward renewable polymer feedstocks but if the source of algae is limited to wild algae species, this may raise issue on the scalability and hinder the creation of a reliable supply chain. In this study, a new phycocolloid extracted from Chaetomorpha aerea, a green seaweed that can be cultivated in open ponds, is identified. Through elucidation of its chemical structure, a gelation mechanism for an extracted sulfated polysaccharide fraction that form stable, transparent hydrogels that can be used for microbiological culture, is proposed Pond‐cultivated seaweed's phycocolloids hold promise for both aquaculture water purification and novel biopolymer sourcing. The isolation and characterization of a phycocolloid from the pond‐cultivable green seaweed Chaetomorpha aerea is reported. Understanding the gelation mechanism of the sulfated polysaccharide fraction enables the creation of a stable substrate for microbiological culture applications.