Mehri Joghataei1, Fakhri Shahidi1, Gholamreza Pouladfar2, Seyed Ali Mortazavi1, Abbas Ghaderi3. 1. Department of Food Science and Technology, Faculty of Agriculture, Ferdowsi University of Mashhad, Mashhad, Iran. 2. Professor Alborzi Clinical Microbiology Research Center, Nemazee Hospital, Shiraz University of Medical Sciences, Shiraz, Iran. 3. Department of Immunology, School of Medicine, Shiraz University of Medical Sciences, Shiraz, Iran.
Abstract
BACKGROUND: Traditional fermented products are a rich source of microorganisms which may have remarkable probiotic properties even more significant than probiotic strains of human origin. In this study three Lactobacillus plantarum and one Lactobacillus fermentum strains, isolated from either Iranian traditionally fermented products or children's feces, identified with molecular methods and selected based on high acid resistance, were investigated for their probiotic properties in vitro and compared with standard probiotic strains of the species; L. plantarum ATCC 14917, L. fermentum PTCC 1744 and L. acidophilus ATCC 4356. RESULTS: Most of the isolates showed a high survival rate under gastrointestinal tract conditions and L. plantarum strains displayed a moderate ability to adhere to human colon adenocarcinoma cell line, HT-29. Neutralized cell free culture supernatants of L. plantarum strains were capable of inhibiting pathogens. Almost all of the strains were resistant to vancomycin and streptomycin and susceptible to other clinically relevant antibiotics. Isolated strains exhibited low to moderate autoaggregation (Auto-A), co-aggregation (Co-A) and hydrophobicity, following a strain specific manner. None of the strains invaded into HT-29 cells while strain PF11 could significantly decrease the number of adhering pathogenic bacteria. Most of the strains increased apoptosis of HT-29 cells, though they had no effect on human umbilical vein endothelial cells (HUVECs). CONCLUSION: Favorable probiotic properties of strains PL4 and PF11 along with their anticancer activity imply their potential for clinical or technological applications. However, further in vitro/in vivo investigations are recommended.
BACKGROUND: Traditional fermented products are a rich source of microorganisms which may have remarkable probiotic properties even more significant than probiotic strains of human origin. In this study three Lactobacillus plantarum and one Lactobacillus fermentum strains, isolated from either Iranian traditionally fermented products or children's feces, identified with molecular methods and selected based on high acid resistance, were investigated for their probiotic properties in vitro and compared with standard probiotic strains of the species; L. plantarumATCC 14917, L. fermentum PTCC 1744 and L. acidophilusATCC 4356. RESULTS: Most of the isolates showed a high survival rate under gastrointestinal tract conditions and L. plantarum strains displayed a moderate ability to adhere to humancolon adenocarcinoma cell line, HT-29. Neutralized cell free culture supernatants of L. plantarum strains were capable of inhibiting pathogens. Almost all of the strains were resistant to vancomycin and streptomycin and susceptible to other clinically relevant antibiotics. Isolated strains exhibited low to moderate autoaggregation (Auto-A), co-aggregation (Co-A) and hydrophobicity, following a strain specific manner. None of the strains invaded into HT-29 cells while strain PF11 could significantly decrease the number of adhering pathogenic bacteria. Most of the strains increased apoptosis of HT-29 cells, though they had no effect on human umbilical vein endothelial cells (HUVECs). CONCLUSION: Favorable probiotic properties of strains PL4 and PF11 along with their anticancer activity imply their potential for clinical or technological applications. However, further in vitro/in vivo investigations are recommended.