传统发酵辣椒制品中乳酸菌分离鉴定及其发酵特性分析OA

To explore high-quality microbial resources,lactic acid bacteria with excellent fermentation performance are screened and isolated from homemade fermented chili peppers in order to develop purebred fermentation agents that can be applied to fermented vegetable products.Six strains of LAB are successfully isolated from the MRS solid culture medium through plate separation technique,designated as JX1-JX5 and JS1.These strains undergo identification via 16S rRNA sequencing,and comprehensive evaluation of their fermentation and functional characteristics.The sequencing results reveals that JX1 and JX5 are identified as Lactiplantibacillus plantarum,while JX2,JX3,and JX4 are classified as Lactobacillus pentosus.Additionally,JS1 is determined to be Weissella hellenica.Among these strains,both JX1 and JX3 exhibit the highest levels of acid production and during the stable period pH≤3.80,along with a pH tolerance of 3.0.Notably,strain JX3 demonstrate superior salt tolerance compared to other strains,displaying significantly higher OD600 values at a 10%salt concentration.The strains JX1-JX5 exhibit a high capacity for nitrite degradation,achieving a degradation rate of 96%within 24 h.The 6 strains exhibit varying degrees of in vitro antioxidant capacity,with the cell suspension demonstrating stronger antioxidant capacity compared to the cell-free extract.Strain JX5 display the highest DPPH clearance rate at 14.67%.Strain JS1 exhibit the highest hydroxyl free radical scavenging rate at 55.74%.The superoxide anion clearance rate is highest in strain JX1,reaching 51.17%.Both strains JX1 and JX5 demonstrate the strongest inhibitory capacity against E.coli,while strain JX3 show the strongest inhibitory capacity against S.aureus.In conclusion,strain JX3 display excellent fermentation characteristics,a strong ability to degrade nitrite,and certain inhibition capabilities against S.aureus,making it suitable for use in pure culture preparation.