Isolation, Identification and Characterization of Some Probiotic Properties of Lactic Acid Bacteria Strains Isolated from Rose Blossom of Rosa damascena Mill.

The study on the isolation, identification, and characterization of probiotic properties of lactic acid bacteria strains from the rose blossom of Rosa damascena Mill. is crucial for discovering novel, plant-derived probiotics with potential health benefits and applications in food, medicine, and cosmetics. Nine lactic acid bacteria (LAB) strains were isolated from rose blossom of Rosa damascena Mill. and they were identified to the species level by applying physiological-biochemical (API 50 CHL) and molecular-genetic (16S rRNA gene sequencing). The isolates were identified as representatives of the species Lactobacillus helveticus, Lactobacillus acidophilus and Lactiplantibacillus plantarum. Some probiotic properties of the newly isolated and identified LAB strains were examined: antimicrobial activity against pathogens by the agar-diffusion method with wells and antibiotic resistance profile by the agar-diffusion method with paper discs. The studied LAB strains demonstrated high antimicrobial activity against the pathogenic bacteria Escherichia coli ATCC 25922, Staphylococcus aureus ATCC 25923, Salmonella abony NTCC 6017, Proteus vulgaris J, Listeria monocytogenes ATCC 19115, Enterococcus faecalis ATCC 29212 and were resistant to most of the antibiotics used in clinical practice, which in turn opens up the possibility of their joint inclusion in complex therapy in the composition of probiotics. A batch fermentation process was carried out with Lactiplantibacillus plantarum 5/20 and the kinetic parameters of the fermentation process to obtain a concentrate with a high content of viable cells (1013cfu/cm3) were determined. The obtained concentrate weas freeze-dried and lyophilic preparations with a high content of viable cells (over 1012 cfu/g) were obtained. This research on Rosa damascena Mill.-isolated LAB strains could uncover valuable LAB strains with significant probiotic properties. These strains would be suitable for various applications in the composition of starters for functional foods and beverages as well as probiotic preparations, showcasing the untapped potential of plant-associated microbiota.