Abstract: In this study, Lactobacillus paracasei FP02, a strain isolated from pickled Chinese cabbage, was tested for its capability to reduce uric acid in vitro, and its physiological and biochemical characteristics were characterized. Furthermore, the effect of this strain on the serum uric acid level of a hyperuricemic (HUA) rat model was explored. The in vitro results showed that L. paracasei FP02 degraded uric acid and its precursor substances, inosine and guanosine, by 29.10%, 67.09%, and 70.48%, respectively, and inhibited xanthine oxidase (XOD) activity by 64.20%. Simultaneously, this strain could ferment various sugars (alcohols) and exhibited good tolerance to gastric acid and bile salts. The 14-day continuous intragastric administration of freeze-dried L. paracasei FP02 powder reduced the serum uric acid concentration by 49.96% compared to the hyperuricemia model group (P < 0.001), which was established by intragastric administration of potassium oxonate combined with high dietary uric acid. After the treatment, the serum uric acid concentration approached the levels observed in the blank control group. Additionally, in the FP02 treatment group, uric acid excretion in the urine increased, and serum XOD activity was significantly inhibited (P < 0.001). Renal sections showed that renal injury was partially restored in the FP02 treatment group. This study will lay the foundation for the development of L. paracasei FP02 as a potential drug or functional food for preventing HUA.

Key words: hyperuricemia; probiotics; Lactobacillus paracasei; renal injury; rat model