ABSTRACT
Objective To compare the effects of kidney calcium oxalate calculus resistant acidophilus milk (KCOCRAM) versus commercially available acidophilus milk (CAAM) on urinary oxalate excretion in rats. Methods Fifty SD rats were randomly divided into 5 groups (n=10), and were bred with KCOCRAM (KCOCRAM group), CAAM (CAAM group), sterilized KCOCRAM (sterilized KCOCRAM group), sterilized CAAM (sterilized CAAM group) and water (blank control group), respectively for a consecutive 20 d, with 4 mL/d for each rat. The data of body weight and 24 h urinary oxalate excretion volume were obtained 1 d before breeding and every 4 d during breeding. Results During breeding, body weight and 24 h urinary oxalate excretion volume of each group increased with time. There was no significant difference in urinary oxalate excretion volume among sterilized KCOCRAM group, sterilized CAAM group and blank control group (P>0.05). The increase tendency of KCOCRAM group and CAAM group was weaker than that of the other three groups. The urinary oxalate excretion volume was significantly lower in KCOCRAM group than that in sterilized KCOCRAM group from 8 d after breeding, and that was significantly lower in CAAM group than that in sterilized CAAM group from 12 d after breeding (P<0.05). The urinary oxalate excretion volume was significantly lower in KCOCRAM group than that in CAAM group from 16 d after breeding (P<0.05). There was a positive correlationship between body weight and 24 h urinary oxalate excretion volume in each group (r＝0.97-0.99, P<0.01). Conclusion Both KCOCRAM and CAAM can reduce urinary oxalate excretion in rats, and the former has a more favourable effect.
ABSTRACT
Objective To investigate the oxalate-degrading abilities of 10 strains of lactic acid bacteria for yoghourt fermentation. Methods Ten different strains of lactic acid bacteria (L.acidophilus, L.paracasei, Enterococcaceae faecium, B. lactis, B. adolescentis, B. infantis, B.longum, Lactococcus lactis subsp. Cremori, L.bulgaricus and S. thermophilus) were cultured separately in culture fluid containing 5 mmol/L oxalate. Seventy-two hours after culture, the concentrations of oxalate and lactic acid bacteria were detected. Besides, blank control cultured without lactic acid bacteria was established. Results Seventy-two hours after culture, the concentrations of all the 10 strains of lactic acid bacteria were significantly higher than those before culture (P<0.01). Compared with blank control, the concentrations of oxalate in the culture fluid with 10 strains of lactic acid bacteria decreased 72 h after culture, and were significantly different from those before culture for L.acidophilus, Lactococcus lactis subsp. Cremori, B.longum, B. adolescentis and B. lactis (P<0.05 or P<0.01). The oxalate-degrading rate of B. lactis was the highest (29.03%), and that of Enterococcaceae faecium was the lowest (0.23%). The correlation analysis revealed that there was no significant correlation between times of proliferation and oxalate-degrading rates (r=0.435 7, P=0.208 2). Conclusion All of the 10 strains of lactic acid bacteria for yoghourt fermentation have the ability of oxalate degrading, and there is no correlation between lactic acid bacteria proliferation and oxalate degradation.