Hypouricemic effect and mechanism of chitooligosaccharide-ionic water in hyperuricemic mice.

BACKGROUND: Hyperuricemia is a prevalent metabolic disorder associated with excessive uric acid (UA) accumulation, oxidative stress, renal dysfunction and gut microbiota dysbiosis. Chitooligosaccharide (COS) possesses antioxidant and microbiota-regulating properties; however, the potential of mineral ion-enriched COS formulations against hyperuricemia remains unclear. In this study, a chitooligosaccharide-ionic water (COS-IW) was prepared by incorporating K, Si, B and Mo mineral components into a chitooligosaccharide matrix, followed by low-temperature concentration to obtain a stable functional formulation. The elemental composition and structural characteristics of COS-IW were characterized by inductively coupled plasma optical emission spectrometry, Fourier transform infrared spectroscopy, 1H-NMR and X-ray diffraction. RESULTS: In hyperuricemic mice, COS-IW significantly decreased serum UA levels and improved renal function by reducing blood urea nitrogen and creatinine levels, accompanied by suppression of xanthine oxidase and adenosine deaminase activities. COS-IW also exhibited strong DPPH (i.e. 2,2-diphenyl-1-picrylhydrazyl) and ABTS [i.e. 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid)] radical scavenging activities in vitro and restored renal superoxide dismutase activity at the same time as reducing malondialdehyde accumulation in vivo. Furthermore, COS-IW reshaped gut microbiota composition, restored microbial diversity, and regulated pathways associated with tryptophan metabolism, butanoate metabolism, purine metabolism and urate homeostasis. CONCLUSION: COS-IW alleviates hyperuricemia through multiple mechanisms involving inhibition of UA production, improvement of renal function, attenuation of oxidative stress and modulation of the gut microbiota-metabolite axis. These findings provide new insights into the application of COS-based mineral ion formulations as functional ingredients for hyperuricemia management. © 2026 Society of Chemical Industry.