Artigo
In vitro probiotic potential and anti-cancer activity of newly isolated folate-producing Streptococcus thermophilus strains
Autor
Duarte, Vinicius da Silva
Tarrah, Armin
Castilhos, Juliana de
Rossi, Rochele Cassanta
Ziegler, Denize Righetto
Corich, Viviana
Giacomini, Alessio
Institución
Resumen
Most probiotic strains commercially available today are lactic acid bacteria. Withinthis functional group, Streptococcus thermophilus is a thermophilic species widely used as starter culture for a huge number of dairy products. Besides being rapid acidifiers, many S. thermophilus strains are able to produce and release folate during growth but, unfortunately, they are seriously impaired during passage through the
human gastrointestinal tract. In this work, we studied eight S. thermophilus strains isolated from dairy environments in Italy, which already had shown good technological properties, to evaluate their possible probiotic potential and cytotoxicity against cancer cells in vitro. All strains were also evaluated for some health-related properties such as susceptibility to most common antibiotics, hemolytic activity, resistance to simulated
gastrointestinal conditions, bile salts hydrolytic activity, production of folate, adhesion to HT-29 human colorectal adenocarcinoma cells and cytotoxic activity against cancer
cells and production of biogenic amines. Results revealed that two fast acidifying S. thermophilus strains were found to possess in vitro probiotic properties along with anticancer activity and production of folate. These properties resulted similar and, in some cases, superior to those of Lactobacillus rhamnosus GG, a well-known commercial probiotic strain. These findings encourage further in vivo studies to evaluate
the actual health benefits of these strains on the human host.