Fatemeh Bagheri,Saeed Mirdamadi, Mahta Mirzaei,Maliheh Safavi
journal of Food Science and Technology,Volume 17, Issue 104 (2020)

The application of probiotic starter cultures in fermented products is expanding in different communities. The genetic variation makes the effects of these bacteria different and unpredictable in different human societies. Therefore, the safety control and evaluation of their non-pathogenicity is of great importance and monitoring centers are required to closely monitor the safety of the bacteria used in food products.
In this study, two strains of Lactobacillus isolated from dairy products of Ardabil (Heyran mountain road villages) and Khuzestan province (Behbahan city) in Iran were identified based on the biochemical and molecular properties through sequence analysis of 16S rRNA gene. Then, their safety was examined based on the international guidelines, especially the European :union: standard. The two identified strains included Lactobacillus fermentum (PTCC 1929) and Lactobacillus helveticus (PTCC 1930). The results showed the lack of gelatinase enzyme, inability of blood hemolysis, inability of amino acids decarboxylation and the lack of genes responsible for the invasive characteristics of pathogenic microorganisms including gelEefaAfm efaAfs , aggacecylM, cylA, cylB.  In addition, the results showed the sensitivity of both isolates to Penicillin, Ampicillin, Rifampicin and Tetracycline, and their resistance to Kanamycin and Ciprofloxacin. Lactobacillus fermentum was resistant to vancomycin, whereas Lactobacillus helveticus was susceptible to it. Since cases of antibiotic resistance are inherent according to scientific reports, the obtained results confirmed the potential application of these two isolated strains as starter in the fermented dairy products. It also confirmed the necessity of using safety assessment procedures for probiotic bacteria.

©  تمامی حقوق متعلق به سازمان پژوهش‌های علمی و صنعتی ایران می باشد.