耐受微酸性次氯酸水乳酸菌的分离鉴定、耐受特性及益生特性

Isolation, identification, and probiotic properties of lactic acid bacteria with tolerance to slightly acidic hypochlorous acid water

摘要:

【背景】次氯酸水具有杀菌性，当其作为饮用水可能会对畜禽肠道内有益菌造成负面影响。【目的】筛选出具有耐受微酸性次氯酸水(slightly acidic hypochlorous acid water, SAHW)能力的乳酸菌并研究其益生特性。【方法】从内蒙古地区传统自然发酵制品中分离筛选出8株乳酸菌菌株，经16S rRNA基因测序进行鉴定。进一步通过耐受SAHW、耐酸、耐胆盐、疏水性及自凝聚能力试验进行耐受特性和益生特性研究。【结果】菌株MBH3-2为副干酪乳杆菌，其经过质量浓度为20 mg/L的SAHW处理2 h，菌落对数值仅下降0.3 lg(CFU/mL)，存活率为50.10%；而且在酸性 (pH 2.0、2.5和3.0)、胆盐环境下均可存活；疏水率达62.12%，属于高度疏水性；自凝聚能力在2 h达到97.29%。【结论】最终确定一株具有优良耐受SAHW及基本满足作为微生态制剂要求的菌株，MBH3-2具有作为新型微生态制剂菌株的潜力。

Abstract:

[Background] The bactericidal hypochlorous acid water may negatively affect the beneficial bacteria in the intestinal tracts of domesticated animals when being used as drinking water. [Objective] To isolate the lactic acid bacteria with tolerance to slightly acidic hypochlorous acid water (SAHW) and investigate their probiotic properties. [Methods] Eight strains of Lactobacillus were isolated from the traditional natural fermentation products in Inner Mongolia and identified by 16S rRNA gene sequencing. The tolerance to SAHW, acid, and bile salt, hydrophobicity, and self-agglutination properties of the isolates were examined. [Results] The strain MBH3-2 was identified as Lactobacillus paracasei. After treatment with 20 mg/L SAHW for 2 h, the strain showed the count decrease of 0.3 lg(CFU/mL) and the survival rate of 50.10%. MBH3-2 was highly hydrophobic with the hydrophobicity of 62.12%, and its self-agglutination rate reached 97.29% at the time point of 2 h. [Conclusion] Strain MBH3-2 with strong tolerance to SAHW and basically meeting the requirements as a microecological preparation was identified, demonstrating the potential to be developed as a new microecological preparation.