Raw milk traditional Italian ewe cheeses as a source of Lactobacillus casei strains with acid-bile resistance and antigenotoxic properties.
Twenty-five Lactobacillus casei group strains isolated from ewe cheeses from Abruzzo region, central Italy, were identified by 16S rRNA gene sequencing, differentiated by RAPD-PCR analysis and characterized as in vitro for acid-bile tolerance and antigenotoxic properties. All the strains were very susceptible to simulated gastric fluid (pH 2.0) but most of them recovered viability (ca. 2-3 log-units) when transferred and maintained in simulated intestinal fluid (0.5% w/v bovine bile) for 3 h. Some strains showed potential for deactivating representative genotoxins as highlighted by the SOS-Chromotest. Twelve were active and nine moderately active against 4-nitroquinoline-1-oxide, and one active and only one moderately active against N-methyl-N'-nitro-N-nitrosoguanidine. The active strains produced evident spectroscopic modification of genotoxins after co-incubation. Most isolates with antigenotoxic activity resulted as acid-bile tolerant demonstrating that cheese autochthonous lactobacilli may reach the gut as a viable form and prevent genotoxin DNA damage.
Dipartimento di Scienze degli Alimenti, Università di Teramo, Via C.R. Lerici 1, 64023 Mosciano S. Angelo, Italy.
Aldo
A
Corsetti
Giovanna
G
Caldini
Mario
M
Mastrangelo
Francesca
F
Trotta
Sara
S
Valmorri
Giovanni
G
Cenci
D015112:4-Nitroquinoline-1-oxide / Q000633:toxicity; D000818:Animals; D001647:Bile Acids and Salts / Q000633:toxicity*; D002611:Cheese / Q000382:microbiology*; D004249:DNA Damage / Q000187:drug effects; D006801:Humans; D006863:Hydrogen-Ion Concentration; D007558:Italy; D007780:Lacticaseibacillus casei / Q000187:drug effects / Q000254:growth & development* / Q000302:isolation & purification*; D019105:Random Amplified Polymorphic DNA Technique / Q000379:methods; D013014:SOS Response, Genetics / Q000235:genetics / Q000502:physiology; D012756:Sheep
D001647:Bile Acids and Salts; D015112:4-Nitroquinoline-1-oxide