Key Laboratory for Food Microbial Technology of Zhejiang Province, Department of Biotechnology, Zhejiang Gongshang University, Hangzhou, Zhejiang, People's Republic of China.
J Appl Microbiol. 2020 Aug;129(2):422-433. doi: 10.1111/jam.14627. Epub 2020 Mar 17.
The aim was to identify a Lactobacillus strain with potential probiotic characteristics by whole-genome sequence analysis and in vitro experimental studies.
The whole-genome sequencing was carried out using PacBio RSII sequencing method and Illumina's paired-end sequencing technology. Gene prediction and annotation were achieved using GlimmerVersion 3.02 and NCBI prokaryotic Genome Annotation Pipeline. Identification was done by biochemical tests and 16S rRNA sequence analysis. mega 6 software was used to build phylogenetic tree. Antagonism against pathogen was determined by agar well diffusion method. Resistance and stability to bile, simulated gastric acid, different salt concentration and thermostability were investigated. Hydrophobicity assay, aggregation assay and anti-oxidation assay were performed to check further probiotic traits. Finally antibiotic susceptibility and acute oral toxicity of the strain in mice were investigated to check its safety status. The strain showed >99% similarity to Lactobacillus paracasei which was further confirmed by biochemical tests. It significantly inhibited pathogens in agar well diffusion assay. It showed tolerance to simulated gastric acid (pH 3), 0·3% bile salt and 10% NaCl. Significant hydrophobic, aggregation and anti-oxidizing activities were observed. No resistance to antibiotics tested was observed and no adverse effects during acute oral toxicity in mice were detected.
Lactobacillus paracasei ZFM 54, a new and safe Lactobacillus strain was identified with numerous probiotic-associated genes and characteristics confirmed by experimental studies.
A new probiotic strain has been identified which is highly stable, safe and suitable to be used in health and food industries.
通过全基因组序列分析和体外实验研究，鉴定具有潜在益生菌特性的乳杆菌菌株。
使用 PacBio RSII 测序方法和 Illumina 的配对末端测序技术进行全基因组测序。使用 GlimmerVersion 3.02 和 NCBI 原核基因组注释管道进行基因预测和注释。通过生化试验和 16S rRNA 序列分析进行鉴定。使用 mega 6 软件构建系统发育树。通过琼脂孔扩散法测定对病原体的拮抗作用。研究了对胆汁、模拟胃酸、不同盐浓度和热稳定性的抗性和稳定性。进行疏水性测定、聚集测定和抗氧化测定以进一步检查益生菌特性。最后，通过检测菌株在小鼠中的抗生素敏感性和急性口服毒性来检查其安全性。该菌株与副干酪乳杆菌的相似度>99%，这进一步通过生化试验得到证实。它在琼脂孔扩散试验中显著抑制了病原体。它对模拟胃酸（pH 3）、0.3%胆汁盐和 10%NaCl 具有耐受性。观察到显著的疏水性、聚集性和抗氧化活性。未观察到对测试抗生素的耐药性，也未在小鼠急性口服毒性试验中观察到不良反应。
鉴定出一种新的安全乳杆菌菌株副干酪乳杆菌 ZFM 54，具有许多益生菌相关基因和特性，通过实验研究得到证实。
鉴定出一种高度稳定、安全且适合用于健康和食品工业的新型益生菌株。
