Determination relationship between oxalate (kidney stone) degredation and exopolysaccharide production of different probiotic strains belonging to Lactobacillus sp.

In this study, Lactobacillus rhamnosus (8), Lactobacillus fermentum (3), Lactobacillus brevis (3), Lactobacillus helveticus (2); 16 strains in total those of which were evaluated after being isolated from several regional cheeses of Turkey have been used. The resistance of Lactobacillusstrains to gastrointestinal system conditions and the protective effects of exopolysaccharide (EPS) that they produce have been investigated. Besides, oxalate tolerance of all strains and EPS productions in that condition have been determined and the strains which are resistive to oxalate conditions and produce high EPS have been evaluated with degragation in different oxalate concentrations (10 mM and 20 mM). As we compare the growing results of Lactobacillus species at pH:2, 50% L. rhamnosus, 34% L. fermentum, and 67% L. brevis have sustained vitality at pH:2. On the other hand, L. helveticus strains have been determined as resistant species to pH:2. All strains in general have been found to progress in 0.3% bile conditions. The average EPS production of the tested Lactobacillus sp. strains has been observed as 229,94 mg/L in L. rhamnosus, 260,02 mg/L in L. fermentum, and 234,98 mg/L in L. brevis and 317,23 mg/L in L. helveticus. The Lactobacillus strains have been found to grow in MRS medium containing 20 mM sodium oxalate, however, it has been determined that their growth at MRS-ox decreases at low rate in comparison with the control group. The EPS production of the strains in 20mM oxalate conditions has been observed between 100,45 and 149,13 mg/L.L. rhamnosus ACS5, SMC5, L. brevis KMP1, BP8 and L. helveticus KMP5, BT11 strains that are resistive to gastrointestinal tract conditions, have high EPS production, and resistive to oxalate conditions and the oxalate degradations of L. rhamnosus BT8 strain, with low performance in regards to these features to compare, have been investigated in varying concentrations of the oxalate (20 mM). L. Helveticus BT11, L. brevis KMP1 ve L. rhamnosus SMC5 strains with high EPS production have been observed to degrade sodium oxalate at a high leveL. As a result of the obtained data, acid-bile resistance, EPS production, and the use of L. brevis KMP1, with high performance in regard to its resistance to sodium oxalate, as a probiotic bacteria in oxalate degradation is recommended.