Competitive inhibition of three novel bacteria isolated from faeces of breast milk-fed infants against selected enteropathogens.
Numerous in vitro and in vivo studies conducted using different probiotic micro-organisms have demonstrated their ability to interfere with the growth and virulence of a variety of enteropathogens. The reported beneficial effects of the use of probiotics to complement antibiotic therapy or prevent diarrhoea or gastrointestinal infection in infants have increased in recent years. In the present study, we demonstrated the capacity of supernatants obtained from three novel probiotics (Lactobacillus paracasei CNCM I-4034, Bifidobacterium breve CNCM I-4035 and Lactobacillus rhamnosus CNCM I-4036) isolated from the faeces of breastfed infants to inhibit the growth of enterotoxigenic and enteropathogenic (EPEC) bacteria, such as Escherichia coli, Salmonella and Shigella. To assess their potential antimicrobial activity, the 17 and 24 h cell-free supernatants broth concentrates (10×) having 1, 2 or 4 % of the three probiotics were incubated with EPEC bacteria strains. After 17 h of co-culture, the supernatants were able to inhibit the growth of E. coli, Salmonella and Shigella up to 40, 55 and 81 %, respectively. However, the inhibitory capacity of some supernatants was maintained or completely lost when the supernatants (pH 3·0) were neutralised (pH 6·5). Overall, these results demonstrated that L. paracasei CNCM I-4034, B. breve CNCM I-4035 and L. rhamnosus CNCM I-4036 produce compounds that exhibited strain-specific inhibition of enterobacteria and have the potential to be used as probiotics in functional foods.
Department of Biochemistry and Molecular Biology II, Institute of Nutrition and Food Technology José Mataix, Biomedical Research Centre, University of Granada, Avenida del Conocimiento s/n, 18100 Armilla, Granada, Spain.
Sergio
S
Muñoz-Quezada
Miriam
M
Bermudez-Brito
Empar
E
Chenoll
Salvador
S
Genovés
Carolina
C
Gomez-Llorente
Julio
J
Plaza-Diaz
Esther
E
Matencio
María José
MJ
Bernal
Fernando
F
Romero
Daniel
D
Ramón
Angel
A
Gil
D000898:Antibiosis; D001644:Bifidobacterium / Q000254:growth & development / Q000302:isolation & purification* / Q000378:metabolism; D001942:Breast Feeding; D017077:Culture Media, Conditioned / Q000378:metabolism; D054308:Enteropathogenic Escherichia coli / Q000254:growth & development / Q000472:pathogenicity; D054307:Enterotoxigenic Escherichia coli / Q000254:growth & development / Q000472:pathogenicity; D005243:Feces / Q000382:microbiology*; D005759:Gastroenteritis / Q000382:microbiology / Q000517:prevention & control*; D006801:Humans; D006863:Hydrogen-Ion Concentration; D007231:Infant, Newborn; D007778:Lactobacillus / Q000254:growth & development / Q000302:isolation & purification* / Q000378:metabolism; D052201:Lacticaseibacillus rhamnosus / Q000254:growth & development / Q000302:isolation & purification / Q000378:metabolism; D050296:Microbial Viability; D019936:Probiotics / Q000302:isolation & purification* / Q000378:metabolism / Q000627:therapeutic use; D012485:Salmonella typhi / Q000254:growth & development / Q000472:pathogenicity; D012486:Salmonella typhimurium / Q000254:growth & development / Q000472:pathogenicity; D012764:Shigella sonnei / Q000254:growth & development / Q000472:pathogenicity; D013030:Spain; D013997:Time Factors
D017077:Culture Media, Conditioned