高效降解草酸乳酸菌的筛选

Screening of efficient Oxalate-degrading Lactic acid bacteria isolated from marketing food and drugs

尿路结石70％～80％主要由草酸钙结晶构成。人体内的草酸一般通过肠道内微生物降解，经由粪便排出或在泌尿道吸收由尿液排出。本研究对市场上商品化的发酵乳制品、饮料和药品中的乳酸菌进行分离，得到37株菌，包括嗜热链球菌、保加利亚乳杆菌、干酪乳杆菌、鼠李糖乳杆菌、植物乳杆菌、嗜酸乳杆菌、动物双歧杆菌、长双歧杆菌、粪肠球菌、屎肠球菌和乳球菌，并检测这些菌株降解草酸的能力。结果提示，乳酸菌在体外能够有效的降低培养物中的草酸浓度，并筛选出了具有高效降解草酸能力的乳酸菌菌株。有望成为尿石症预防的新措施。

70% -80% urolithiasis was due to calcium-oxalate crystal. Oxalate from food was either degraded by mi- croorganisms in the large intestine, excreted unchanged in the faeces, or was absorbed into the urinary tract and excreted in urine. To investigate the oxalate-degrading abilities of lactic acid bacteria used in marketing foods in Shanghai Ch/na. We i- solated 37 strains from different sources, including 13 S. thermophilus, 6 Lb. bulgaricus, 2 Lb. casei, 2 Lb. rhamnosus, 3 Lb. plantarum , 2 Lb. acidophilus , 2 B. animalis , 1 B. longum , 3 E. faecaIis , 1 E. faecium and 2 Lc. lactis. After cul- tured in the 5 mmol/L oxalate-contained medium for 5 days, the residual concentrations of oxalate were detected. The re- sults indicated that all isolated strains have the ability to degrade oxalate, and high-efficient strains were selected. These bacteria may, therefore, be of use in the prophylactic treatment of oxalate kidney stone disease.