摘要
以清除DPPH自由基和还原能力为指标,对实验室保藏的25株乳酸菌的菌体和无细胞提取物进行体外抗氧化性研究;将抗氧化性强的10株乳酸菌,进行对模拟胃液酸度和肠道胆盐的耐受性研究,比较不同乳酸菌株的抗氧化和耐酸耐胆盐能力,为开发功能性乳酸菌食品提供理论依据。研究表明:不同属和同属的不同菌株的乳酸菌抗氧化能力和耐酸耐胆盐存在差异,且其抗氧化活性物质存在部位不同。比较发现干酪乳杆菌GL-2抗氧化性高且耐酸耐胆盐。干酪乳杆菌GL-2菌体浓度为109cfu/mL时,菌体和无细胞提取物DPPH自由基清除率分别为37.22%、42.78%,还原活性分别相当于104.84、107.10μmol/L L-半胱氨酸;pH=3.0的酸性缓冲溶液处理2h后存活率均达100%,在改良MRS培养基(胆盐为0.5%(W/V))处理4h存活率为0.35%。
The antioxidant capabilities of 25 lactic acid bacteria in vitro from intact cells,cell-free extracts were evaluated through scavenging DPPH free radicals and reducing activities methods. The 25 strains of 10 strains lactic acid bacteria with higher antioxidant activities were further studied,acid and bile salt tolerance were researched by stimulating human gastric acid and intestinal bile salt condition. In order to provide theoretical foundation for developing functional food,lactic acid bacteria with antioxidant activity and acid and bile salt tolerance activity were compared in this paper. Different genera and different strains of the same genus of lactic acid bacteria exhibited different antioxidant activity and acid and bile salts tolerance,antioxidant places also exhibited different antioxidant activities. L. caseiGL-2 displayed the excellent antioxidant activity and acid and bile salt tolerance among 25 lactic acid bacterial strains.The result showed that the scavenging DPPH free radical of intact cells and cell-free extracts of L.caseiGL-2 were 37.22% and 42.78% respectively when its biomass concentration was 109cfu/mL,the reduced activity was equivalent to 104.84μmol/L and 107.10μmol/L that of L-cysteine,after treated with pH3.0 acid buffer solution for 2h,the survival rate of L. caseiGL-2 was 100%,in the MRS medium containing bile salt 0.5%（W/V）,the survival rate of L. caseiGL-2 was 0.35%.
出处
《食品工业科技》
CAS
CSCD
北大核心
2014年第2期92-96,99,共6页
Science and Technology of Food Industry
基金
光明乳业股份有限公司乳业生物技术国家重点实验室开放基金(SKLDB2011-005)
上海市科委工程中心建设(11DZ2280300)
关键词
乳酸菌
抗氧化性
耐酸耐胆盐
lactic acid bacteria
antioxidant capacity
acid and bile salt tolerance
