title: Molecular identification and quantification of lactic acid bacteria in traditional fermented dairy foods of Russia.
abstract: Russian traditional fermented dairy foods have been consumed for thousands of years. However, little research has focused on exploiting lactic acid bacteria (LAB) resources and analyzing the LAB composition of Russian traditional fermented dairy foods. In the present study, we cultured LAB isolated from fermented mare and cow milks, sour cream, and cheese collected from Kalmykiya, Buryats, and Tuva regions of Russia. Seven lactobacillus species and the Bifidobacterium genus were quantified by quantitative PCR. The LAB counts in these samples ranged from 3.18 to 9.77 log cfu/mL (or per gram). In total, 599 LAB strains were obtained from these samples using de Man, Rogosa, and Sharpe agar and M17 agar. The identified LAB belonged to 7 genera and 30 species by 16S rRNA and murE gene sequencing and multiplex PCR assay. The predominant LAB isolates were Lactobacillus helveticus (176 strains) and Lactobacillus plantarum (63 strains), which represented 39.9% of all isolates. The quantitative PCR results revealed that counts of 7 lactobacilli species and Bifidobacterium spp. of 30 fermented cow milk samples ranged from 1.19±0.34 (Lactobacillus helveticus in Tuva) to 8.09±0.71 (Lactobacillus acidophilus in Kalmykiya) log cfu/mL of fermented cow milk (mean ± standard error). The numbers of Bifidobacterium spp., Lb. plantarum, Lb. helveticus, and Lb. acidophilus revealed no significant difference between the 3 regions; nevertheless, Lactobacillus paracasei, Lactobacillus fermentum, Lactobacillus sakei, and Lactobacillus delbrueckii ssp. bulgaricus exhibited different degrees of variation across 3 regions. The results demonstrate that traditional fermented dairy products from different regions of Russia have complex compositions of LAB species. The diversity of LAB might be related to the type of fermented dairy product, geographical origin, and manufacturing process.
authors.affiliation: Key Laboratory of Dairy Biotechnology and Engineering, Education Ministry of P. R. China, Inner Mongolia Agricultural University, Hohhot, Inner Mongolia 010018, P. R. China.
authors.forename: J
authors.initials: J
authors.lastname: Yu
authors.affiliation: Key Laboratory of Dairy Biotechnology and Engineering, Education Ministry of P. R. China, Inner Mongolia Agricultural University, Hohhot, Inner Mongolia 010018, P. R. China.
authors.forename: H M
authors.initials: HM
authors.lastname: Wang
authors.affiliation: Key Laboratory of Dairy Biotechnology and Engineering, Education Ministry of P. R. China, Inner Mongolia Agricultural University, Hohhot, Inner Mongolia 010018, P. R. China.
authors.forename: M S
authors.initials: MS
authors.lastname: Zha
authors.affiliation: Key Laboratory of Dairy Biotechnology and Engineering, Education Ministry of P. R. China, Inner Mongolia Agricultural University, Hohhot, Inner Mongolia 010018, P. R. China.
authors.forename: Y T
authors.initials: YT
authors.lastname: Qing
authors.affiliation: Key Laboratory of Dairy Biotechnology and Engineering, Education Ministry of P. R. China, Inner Mongolia Agricultural University, Hohhot, Inner Mongolia 010018, P. R. China.
authors.forename: N
authors.initials: N
authors.lastname: Bai
authors.affiliation: Key Laboratory of Dairy Biotechnology and Engineering, Education Ministry of P. R. China, Inner Mongolia Agricultural University, Hohhot, Inner Mongolia 010018, P. R. China.
authors.forename: Y
authors.initials: Y
authors.lastname: Ren
authors.affiliation: Key Laboratory of Dairy Biotechnology and Engineering, Education Ministry of P. R. China, Inner Mongolia Agricultural University, Hohhot, Inner Mongolia 010018, P. R. China.
authors.forename: X X
authors.initials: XX
authors.lastname: Xi
authors.affiliation: Key Laboratory of Dairy Biotechnology and Engineering, Education Ministry of P. R. China, Inner Mongolia Agricultural University, Hohhot, Inner Mongolia 010018, P. R. China.
authors.forename: W J
authors.initials: WJ
authors.lastname: Liu
authors.affiliation: Key Laboratory of Dairy Biotechnology and Engineering, Education Ministry of P. R. China, Inner Mongolia Agricultural University, Hohhot, Inner Mongolia 010018, P. R. China.
authors.forename: B L G
authors.initials: BL
authors.lastname: Menghe
authors.affiliation: Key Laboratory of Dairy Biotechnology and Engineering, Education Ministry of P. R. China, Inner Mongolia Agricultural University, Hohhot, Inner Mongolia 010018, P. R. China. Electronic address: hepingdd@vip.sina.com.
authors.forename: H P
authors.initials: HP
authors.lastname: Zhang
mesh_terms: D001426:Bacterial Proteins / Q000235:genetics*; D043302:Cultured Milk Products / Q000382:microbiology*; D004269:DNA, Bacterial / Q000235:genetics*; D005516:Food Microbiology; D007777:Lactobacillaceae / Q000235:genetics* / Q000302:isolation & purification; D008969:Molecular Sequence Data; D060885:Multiplex Polymerase Chain Reaction; D010802:Phylogeny; D012336:RNA, Ribosomal, 16S / Q000235:genetics*; D011938:Rec A Recombinases / Q000235:genetics; D012426:Russia; D017422:Sequence Analysis, DNA
chemical_list: D001426:Bacterial Proteins; D004269:DNA, Bacterial; D012336:RNA, Ribosomal, 16S; D011938:Rec A Recombinases
keywords: 16S rRNA gene; lactic acid bacteria; quantitative PCR; traditional fermented dairy product