Oral mucositis is a factor that diminishes patients' quality of life (QOL). However, current treatments for oral mucositis face challenges, including poor retention of active ingredients and discomfort during intraoral application. Various water-soluble polymers are used in formulations applied to the oral cavity. Additionally, plant-derived components with antimicrobial activity are gaining attention as potential ingredients to prevent the onset and promote healing of oral mucositis. Therefore, this study focused on xyloglucan (Xylo), which gels upon the addition of polyols. Hydrogels and xyloglucan films were prepared by mixing Xylo with epigallocatechin gallate (EGCG), which has antioxidant and antibacterial properties, and their physicochemical properties were evaluated.

Hydrogels were prepared by mixing a Xylo solution (1.5 w/w%) with EGCG solutions at various concentrations (0.1, 0.25, 0.5, 0.75, 1.0, and 2.0 w/w%), then dispensing the mixture and storing it at 4°C for 24 hours. The hydrogels were then left to stand for an additional 5 days, dried, and formed xerogel films. The tensile strength of the hydrogels, along with the adhesion and water absorption of the xerogels, were evaluated. Additionally, ascorbic acid was added to enhance stability, and the results were analyzed.

As the EGCG content increased, gel transparency decreased. In the tensile strength test, the hydrogel with 2.0% EGCG showed the highest strength and elongation at break. Regarding adhesion, it measured 1.8 N for 0.25% EGCG and 2.0 N for 2.0% EGCG. Although no significant difference was observed with different EGCG concentrations, the adhesion was similar to that of existing formulations. In the water absorption test, the 0.1% EGCG Xylo gel demonstrated a high water absorption rate. These results indicate that adjusting the EGCG content enables control over the film's strength, flexibility, and water absorption. Therefore, EGCG-containing Xylo gel is suitable for use in film formulations designed for treating oral mucositis.