DETERMINATION OF THE HYALURONIC ACID PRODUCTION POTENTIAL AND RELATED GENES OF Streptococcus thermophilus STRAINS ISOLATED FROM TRADITIONAL YOGHURTS
Project no. 21789 · Status: Kapanmış (Yayın bekleniyor) · 2020
Summary
In this study, lactic acid bacteria (LAB) isolated from yoghurts produced by traditional methods in different regions of Turkey and hyaluronic acid (HA) production capacities of Streptococcus thermophilus RSKK 04082 strain used as a reference were investigated. Among the isolates, a LAB similar to the reference strain was selected and identified as Enterococcus faecium (D4-16). By genotypic identification. Viable cell counts were made over a 38-hour period and it was determined that S. thermophilus RSKK 04082 and E. faecium (D4-16) cells reached 10.11 log cfu/mL and 9.75 log cfu/mL, respectively, with the highest number of viable cells at 18th hour. The carbazole method was used to determine the concentration of HA, which is known to be the primary metabolite, and the amounts of HA were determined by considering the standard curve drawn using the glucuronic acid standard. It was determined that S. thermophilus RSKK 04082 and E. faecium (D4-16) reached the highest HA concentration at the 16th hour and was 66.92 mg/L and 64.50 mg/L, respectively. According to Fourier transform infrared spectrophotometer (FTIR), the exopolysaccharides produced by both microorganisms were determined to be HA. In addition, primers were designed to identify genes responsible for HA production and PCR was performed with genomic DNA of both S. thermophilus and E. faecium (D4-16), and a region thought to be the hasA gene region was amplified from both strains.