Bio-Based k-Carrageenan/Degalactosylated Xyloglucan Hydrogels Bioink for Scaffolds 3D Printing

The transition toward sustainable, bio-based materials is a key objective in industrial biotechnology, driving the replacement of fossil-derived polymers with renewable alternatives in advanced manufacturing and biomedical applications. In this context, polysaccharide hydrogels are particularly attractive due to their biodegradability, low environmental impact, and ability to form functional networks under mild conditions. Hybrid hydrogels based on plant-derived κ-carrageenan (k-C) and degalactosylated xyloglucan (Deg-XG) represent a fully bio-based and scalable platform for cell-compatible 3D printing. κ-Carrageenan is a red-algae–derived sulfated polygalactan whose thermoresponsive gelation and glycosaminoglycan-like structure make it a promising biomaterial for soft-tissue scaffolding. However, its intrinsic brittleness and limited porosity restrict its applicability in extrusion-based fabrication. Degalactosylated xyloglucan, obtained via enzymatic removal of galactose residues from tamarind-seed xyloglucan, forms soft, adhesive, and biocompatible hydrogels. When blended with k-C, Deg-XG enhances swelling behavior, microporosity, and elasticity, yielding hybrid networks with improved structural stability while preserving a fully renewable origin. In this study, aqueous k-C/Deg-XG hydrogels were investigated as sustainable bioinks for extrusion-based 3D printing. Rheological analyses were performed to evaluate gel behavior during processing, and printing parameters were optimized to achieve higher print fidelity. Preliminary tests with adipose-derived stem cell spheroids confirmed cytocompatibility, highlighting the potential of k-C/Deg-XG hydrogels for renewable, plant-based bioinks in tissue engineering.