从发酵蔬菜中分离到乳杆菌 DMDL 9010，将此菌与 LCR 719、 LB 1．83、 ST 1．204和 LP 8140 等4 株乳酸菌用于 MRS 培养基体系中亚硝酸盐的降解，作用24h 后发现，DM-DL 9010 的降解效果最好并具有显著性(P≤0．001)．利用 16SrDNA 将鉴别的范围缩小到植物乳杆菌(Lactobacillus plantarum)或戊糖乳杆菌(Lactobacillus pentosus)，生理生化实验将 DMDL 9010 鉴定为戊糖乳杆菌．但在后续的 PCR 中无法得到戊糖乳杆菌的特异性条带．通过分析两种菌的基因组序列，发现它们都具有编码 L- 乳酸脱氢酶 1 的同源 DNA 序列(ldhL1)，序列相似度达到 90%．同时这段同源序列上下游片段序列相似度较低，其序列的差异可以作为鉴别依据．对 DMDL 9010 的 L- 乳酸脱氢酶 1 基因上下游 900bp 左右的DNA 片段进行 PCR 扩增并测序，利用生物信息学分析方法进行序列比对分析，DMDL9010 被鉴定为植物乳杆菌．

Lactobacillus sp.DMDL 9010 was isolated from fermented vegetables and was used for the degradation ofnitrites in MRS broth,and the results are compared with those of other four lactic acid bacteria including LCR 719,LB 1.83,ST 1.204 and LP 8140,with the best nitrite degradation effect of DMDL 9010 after 24- h fermentation(P≤0.001) being revealed. Then,the identification scope of DMDL 9010 was reduced to Lactobacillus plantarumand Lactobacillus pentosus with the help of 16S rDNA sequence,and the strain was identified as L.pentosus by tes-ting physiological and biochemical characters,although no specific stripe was obtained in the subsequent PCR.More-over,a homologous DNA sequence of L- lactate dehydrogenase 1 (ldhL1) with a similarity of 90% was found in thegenome of L.pentosus and L.plantarum,and the low DNA sequence similarity in the upstream and downstreamfragments of ldhL1 could be regarded as an identification criterion of the two strains.Finally,after the PCR amplifi-cation and sequencing of the upstream and downstream fragments of ldhL1,the above- mentioned sequences werecompared via the bioinformatics analysis,and DMDL 9010 was identified as L.plantarum.