Hydrogel and membrane scaffold formulations of Frutalin (breadfruit lectin) within a polysaccharide galactomannan matrix have potential for wound healing

Plant lectins are carbohydrate-binding proteins, which can interact with cell surfaces to initiate anti-inflammatory pathways, as well as immunomodulatory functions. Here, we have extracted, purified and part-characterized the bioactivity of Jacalin, Frutalin, DAL and PNA, before evaluating their potential for wound healing in cultured human skin fibroblasts. Only Frutalin stimulated fibroblast migration in vitro, prompting further studies which established its low cytotoxicity and interaction with TLR4 receptors. Frutalin also increased p-ERK expression and stimulated IL-6 secretion. The in vivo potential of Frutalin for wound healing was then assessed in hybrid combination with the polysaccharide galactomannan, purified from Caesalpinia pulcherrima seeds, using both hydrogel and membrane scaffolds formulations. Physical-chemical characterization of the hybrid showed that lectin-galactomannan interactions increased the pseudoplastic behaviour of solutions, reducing viscosity and increasing Frutalin's concentration. Furthermore, infrared spectroscopy revealed -OH band displacement, likely caused by interaction of Frutalin with galactose residues present on galactomannan chains, while average membrane porosity was 100 μm, sufficient to ensure water vapor permeability. Accelerated angiogenesis and increased fibroblast and keratinocyte proliferation were observed with the optimal hybrid recovering the lesioned area after 11 days. Our findings indicate Frutalin as a biomolecule with potential for tissue repair, regeneration and chronic wound healing.