Rositsa DENKOVA, Lyubka GEORGIEVA, Zapryana DENKOVA, Svetla ILIEVA, Velichka YANAKIEVA


Restoring the balance of the intestinal microflora is achieved by consummation of foods and concentrates, containing beneficial bacteria - lactobacilli and bifidobacteria - known as functional foods and probiotics. Not all lactobacilli can be included in the composition of probiotics and probiotic foods, but only those who possess certain properties. Identification of the strain Lactobacillus LBRC11 is achieved through the application of physiological and biochemical (API 50 CHL) and molecular genetic (ARDRA) methods. The antimicrobial activity against saprophytic microorganisms (Bacillus subtilis, Bacillus mesentericus, Aspergillus niger, Penicillium sp., Rhizopus sp., Saccharomyces cerevisiae) is determined using the agar diffusion method and the antimicrobial activity against pathogens (E.coli ATCC 25922, E.coli 8739, Salmonella abony, Salmonella sp., Staphylococcus aureus ATCC 25093) is investigated by carrying out joint cultivation. The profile of antibiotic resistance is determined by the method of diffusion in agar. The enzymatic profile of the strain is studied with the test kit API ZYM. By applying API 50 CHL and ARDRA the strain Lactobacillus LBRC11 is identified as Lactobacillus casei ssp.rhamnosus. The strain possesses antimicrobial activity against the saprophytes Bacillus mesentericus, Aspergillus niger, Penicillium sp., Rhizopus sp. and against all of the pathogens included in the study. Lactobacillus casei ssp.rhamnosus LBRC11 is resistant to 8 of the 22 antibiotics used in the study and is sensitive to 10 of them. The results of the tests on some probiotic properties of Lactobacillus casei ssp.rhamnosus LBRC11 make it suitable for incorporation in probiotics and probiotic foods.

Full Text:



  • There are currently no refbacks.