摘要
该实验对Lactobacillus plantarum、Lactobacillus brevis、Lactobacillus rhamnosus的产酸特性、NO_2^-降解能力、16S r DNA序列及其亚硝酸盐还原酶(nitrite reductase,NiR)蛋白序列进行了研究与分析。结果表明,Lactobacillus brevis降解NO_2^-能力最强,可能是该菌有nir基因,在NO_2^-的诱导下产生NiR;该菌产酸量较低,较少的H^+和NiR降解NO_2^-生成的氨类物质,使发酵环境一直处于NiR最适作用p H值(5.0～6.0),从而使NO_2^-大量被NiR分解。Lactobacillus plantarum与Lactobacillus brevis亲缘关系较近,当环境p H值>4.5时,它主要在NiR作用下分解NO_2^-;但Lactobacillus plantarum产酸能力较强,能快速使环境p H值<4.0,从而迅速进入NO_2^-被H^+降解阶段。Lactobacillus rhamnosus与Lactobacillus brevis和Lactobacillus plantarum亲缘关系较远,没有找到nir基因,但Lactobacillus rhamnosus产酸能力较强,其降解NO_2^-机理可能主要是酸降解。
The acidogenic characteristics,NO2^- degradation abilities,16S rDNA sequences,and amino acid sequences of nitrite reductases (NiR) of Lactobacillus plantarum,Lactobacillus brevis,and Lactobacillus rhamnosus were analyzed.It was found that L.brevis had the strongest ability to degrade nitrite as it may contain nir that could be translated into NiR under NO2^- induction.Nevertheless,it had low acid yield.Therefore,less H^+ and NiR degraded ammonia-formed substances produced by NO2^-,causing the fermentation environment was always at the optimum pH of NiR (5.0-6.0),resulting large amount of NO2^- could be decomposed by NiR.L.plantarum was closely related to L.brevis.When the pH value was >4.5,it mainly decomposed NO2^- by NiR.However,L.plantarum had strong acid-producing ability and could quickly make the pH to be lower than 4.0,and NO2^- was consequently degraded by H +.L.rhamnosus had a remote relationship with L.brevis and L.plantarum.It had no nir,but its acid production ability was strong.Therefore,its NO2^- degradation mechanism might mainly be acid degradation.
作者
王一茜
荣金诚
王晓辉
迟乃玉
张庆芳
李美玉
WANG Yiqian;RONG Jincheng;WANG Xiaohui;CHI Naiyu;ZHANG Qingfang;LI Meiyu(College of Life Science and Technology,Dalian University,Dalian 116622,China;Liaoning Marine Micr-obial Engineering and Technology Center,Dalian 116622,China)
出处
《食品与发酵工业》
CAS
CSCD
北大核心
2019年第8期50-56,共7页
Food and Fermentation Industries
基金
国家高技术研究发展计划"863计划"项目(No.2018YFC0311100)
国家高技术研究发展计划"863计划"项目(No.2014AA093512)
