Volume 55 (2005) Issue: 2005 No#5-6

Molecular characterization of semi-hard homemade cheese microflora

Author(s): Jovčić B, Golić Nataša, Kojić M, Topisirović Lj

Keywords:cheese, DNA, LAB, PCR, RFLP

This decade has shown an impressive development in the application of molecular techniques based on 16S and 23S rRNA genes to study the microbial diversity in various ecosystems. Microflora of semi-hard homemade cheese was examined in this work. We developed a novel technique for DNA extraction (a bead beating based method) due to high fat content of this cheese. Rapid extraction of DNA from cheese microflora enabled a molecular identification of the LAB (Lactic Acid Bacteria) strains based on PCR amplification of 16S RNA coding sequences. The specific primers for 16S RNA gene of lactobacilli were used for amplification. The PCR reaction was performed at lower temperature, where the specificity of the annealing reaction was reduced, and lactococcal sequences of 16S RNA genes were also amplified. The results of RFLP analysis revealed that the microflora of Doboj homemade cheese encompases mostly lactococci.