Preparation, characterization and antibacterial investigation of water-soluble curcumin-chitooligosaccharide complexes

Curcumin has a wide range of application prospects, with various bioactivities in the food industry and in the biomedical field. However, curcumin has poor water solubility and is sensitive to pH, light and temperature. In this study, curcumin-chitooligosaccharide (CUR-COS) complexes were prepared via mechanochemical methods, and the CUR-COS complex was more soluble after freeze-drying (up to 862-fold greater than that of curcumin). The complex was characterized by SEM, XRD, FT-IR and thermal analysis, and its stability against pH, light and thermal treatment was evaluated. COSs could serve as carriers for curcumin delivery. Additionally, the antibacterial activity of the formed complex was determined. As a result, CUR-COS exhibited significantly better water solubility, enhanced stability, and stronger antibacterial properties than did pure CUR, offering a promising pathway for the extensive application of lipophilic natural products in foods, especially water-based products.