Lactobacillus bulgaricus mutants decompose uremic toxins.

BACKGROUND/AIMS: We aim to obtain a probiotic strain from Lactobacillus bulgaricus by testing its capability to decompose uremic toxins to provide new intestinal bacteria for the treatment of chronic renal failure.

METHODS

Original L. bulgaricus was cultured with the serum of uremic patients and then mutated by physical (ultraviolet) and chemical (diethyl sulfate) methods repeatedly. Using creatinine decomposition rate as an observed index, we selected the best strains which decreased the most concentration of the creatinine. We then tested its ability to decompose urea, uric acid, serum phosphate, parathyroid hormone, and homocysteine and its genetic stability.

RESULTS

After inductive and mutagenic treatment, DUC3-17 was selected. Its decomposition rate of creatinine, urea nitrogen, uric acid, phosphorus, parathyroid hormone, and homocysteine were 17.23%, 36.02%, 9.84%, 15.73%, 78.26%, and 12.69%, respectively. The degrading capacity was sustained over five generations.

CONCLUSIONS

After directional induction and compound mutation, L. bulgaricus has greater capacity to decompose uremic toxins, with a stable inheritance.