A taxonomic survey of lactic acid bacteria isolated from wheat (Triticum durum) kernels and non-conventional flours

Syst Appl Microbiol. 2007 Nov;30(7):561-71. doi: 10.1016/j.syapm.2007.07.001. Epub 2007 Aug 1.

Abstract

In order to explore the correspondence between raw material- and mature sourdough-lactic acid bacterial (LAB) communities, 59 Italian wheat (Triticum durum) grain samples, one bran and six non-conventional flour samples were analyzed through a culture-dependent approach. The highest cell count by an agar medium specific for LAB was 2.16 log CFU/g. From about 2300 presumptive LAB (Gram-positive and catalase-negative) colonies collected, a total of 356 isolates were subjected to identification by a genetic polyphasic strategy consisting of RAPD-PCR analysis, partial 16S rRNA gene sequencing, species-specific and multiplex PCRs. The isolates were recognized as 137 strains belonging to Aerococcus, Enterococcus, Lactobacillus, Lactococcus and Pediococcus genera and a phylogram based on partial 16S rRNA genes was constructed. The species most frequently found were Enterococcus faecium, Enterococcus mundtii and Lactobacillus graminis, which are not generally reported to be typical in mature sourdoughs.

MeSH terms

  • Catalase / analysis
  • Colony Count, Microbial
  • DNA Fingerprinting
  • DNA, Bacterial / chemistry
  • DNA, Bacterial / genetics
  • DNA, Ribosomal / chemistry
  • DNA, Ribosomal / genetics
  • Dietary Fiber / microbiology*
  • Edible Grain / microbiology
  • Flour / microbiology*
  • Genes, rRNA
  • Gram-Positive Bacteria / classification*
  • Gram-Positive Bacteria / genetics
  • Gram-Positive Bacteria / isolation & purification*
  • Italy
  • Lactic Acid / metabolism*
  • Molecular Sequence Data
  • Phylogeny
  • RNA, Bacterial / genetics
  • RNA, Ribosomal, 16S / genetics
  • Random Amplified Polymorphic DNA Technique
  • Sequence Analysis, DNA
  • Sequence Homology, Nucleic Acid
  • Triticum / microbiology*

Substances

  • DNA, Bacterial
  • DNA, Ribosomal
  • Dietary Fiber
  • RNA, Bacterial
  • RNA, Ribosomal, 16S
  • Lactic Acid
  • Catalase