乳酸片球菌HAO2018胞外多糖的生物活性研究

Biological activity of exopolysaccharides from Pediococcus acidilactici HAO2018

以一株从酱香型白酒酒醅中筛选分离的乳酸片球菌Pediococcus acidilactici HAO2018为研究对象,探究菌株耐酸、耐胆盐特性及耐药性;用乙醇沉淀法提取该菌株胞外多糖(exopolysaccharides,EPS),对其抗氧化、抗菌、抗肿瘤等生物活性进行评价。结果表明,乳酸片球菌HAO2018具有较好的耐酸、耐胆盐能力,对卡那霉素等多种抗生素敏感,对万古霉素、复方新诺明不敏感;其EPS的DPPH自由基、羟自由基清除率以及还原能力均以浓度依赖的方式增加,当EPS质量浓度为1.0 mg/mL时,对DPPH的清除率为(68.46±4.16)%,当EPS质量浓度为10.0 mg/mL时,还原力以及羟自由基清除率分别为(54.10±0.15)%、(83.43±3.87)%;HAO2018的EPS对食源性致病菌志贺氏菌和阪崎克罗诺杆菌具有显著的抑制效果;EPS的抗肿瘤活性呈现浓度依赖性,0.5~2 mg/mL的EPS作用48 h和72 h时显著地抑制HT-29细胞的增殖。该研究对乳酸片球菌胞外多糖的综合开发利用提供一定理论基础。

A strain of Pediococcus acidilactici HAO2018 isolated from fermented grains of Maotai-flavor Baijiu was taken as the research object to explore its acid tolerance,bile salt tolerance,and drug resistance.Exopolysaccharides(EPS) of this strain were extracted by ethanol precipitation method,and their biological activities such as anti-oxidation,anti-bacterial and anti-tumor were evaluated.Results showed that P.acidilactici HAO2018 had good acid and bile salt tolerance,was sensitive to multiple antibiotics such as kanamycin,etc.,and was not sensitive to vancomycin and cotrimoxazole.The DPPH free radical,hydroxyl radical scavenging rates and reducing ability of EPS increased in a concentration-dependent manner.When the concentration of EPS was 1.0 mg/mL,the DPPH scavenging rate was(68.46±4.16)%.When the concentration of EPS was 10.0 mg/mL,the reducing ability and hydroxyl radical scavenging rate were(54.10±0.15)% and(83.43±3.87)%,respectively.The EPS of the strain HAO2018 had a significant inhibitory effect on food borne pathogenic bacteria Shigella and Cronobacter sakazakii.The anti-tumor activity of EPS was concentration-dependent.0.5-2 mg/mL EPS treatment significantly inhibited the proliferation of HT-29 cells at 48 h and 72 h.These studies provide a theoretical basis for the comprehensive development and utilization of the exopolysaccharides of Pediococcus acidilactici.