Antimicrobial potential of four Lactobacillus strains isolated from breast milk.
OBJECTIVE
The antimicrobial potential of four lactobacilli (Lactobacillus salivarius CECT5713, Lactobacillus gasseri CECT5714, L. gasseri CECT5715 and Lactobacillus fermentum CECT5716), isolated from fresh human breast milk, was evaluated in this study and compared with Lactobacillus coryniformis CECT5711, a reuterin-producing strain isolated from an artisan goat's cheese.


RESULTS
Agar diffusion tests, competitive adhesion assays and mucin expression assays were carried out in order to value the antibacterial properties of the lactobacilli strains. The antibacterial capability of the strains was tested in vivo by using a murine infection model with Salmonella choleraesuis. The results revealed that all the strains studied, displayed antibacterial properties against pathogenic bacteria. However, the antibacterial potential varied among the lactobacilli tested and, in fact, L. salivarius CECT5713 showed not only the best in vitro antibacterial activity, but also the highest protective effect against a Salmonella strain in the murine infection model.


CONCLUSIONS
The four breast-milk lactobacilli, and particularly L. salivarius CECT5713, possess potent antibacterial activities that result in a higher protection against S. choleraesuis CECT4155 in a mouse infection model.


CONCLUSIONS
These results suggest that lactobacilli from breast milk could contribute to an anti-infective protection in neonates and would be excellent candidates for the development of infant probiotic products.
Olivares
M
M
Immunology and Animal Science Department, Puleva Biotech SA, Granada, Spain. molivares@pulevabiotech.es
Díaz-Ropero
M P
MP
Martín
R
R
Rodríguez
J M
JM
Xaus
J
J
D000818:Animals; D000898:Antibiosis; D001422:Bacterial Adhesion; D001431:Bacteriological Techniques; D002460:Cell Line; D048014:Clostridium tyrobutyricum; D004926:Escherichia coli; D019453:Escherichia coli O157; D005260:Female; D005516:Food Microbiology; D006801:Humans; D007778:Lactobacillus / Q000302:isolation & purification / Q000502:physiology*; D052197:Limosilactobacillus fermentum / Q000302:isolation & purification / Q000502:physiology; D008089:Listeria monocytogenes; D051379:Mice; D008807:Mice, Inbred BALB C; D008895:Milk, Human / Q000382:microbiology*; D009077:Mucins / Q000235:genetics; D019936:Probiotics; D012475:Salmonella; D012480:Salmonella Infections / Q000628:therapy; D013045:Species Specificity; D013211:Staphylococcus aureus
D009077:Mucins