In vitro Probiotic Potential and Anti-cancer Activity of Newly Isolated Folate-Producing Streptococcus thermophilus Strains

Abstract

Most probiotic strains commercially available today are lactic acid bacteria. Within this 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.

A metagenome association study of gut microbiome revealed biomarkers for chemotherapy efficacy in locally advanced and advanced lung cancer

“…The abundance of Streptococcus thermophilus was obviously reduced in patients with a history of long-term smoking. Streptococcus thermophilus possess in vitro probiotic properties along with anticancer activity [36]. Therefore, taking into consideration previous microbiome studies and our correlation analysis, we recommend quitting smoking to maintain the abundance of bene cial bacteria.…”

Preparation of herbal curd with Gymnema sylvestre and its characterization for the treatment of liver cancer

“…Lactic acid bacteria, such as Lactobacillus fermentum NCIMB 5221 was more potent in suppressing cancer cells and promoting normal epithelial cell growth by the production of short‐chain fatty acids (Kahouli, Malhotra, Alaoui‐Jamali, & Prakash, ). Streptococcus thermophilus strains were found to possess in vitro probiotic properties along with anticancer activity (Tarrah et al, ). In this study, both Lactobacillus and Streptococcus were used for the preparation of curd as well as herbal curd.…”

“…Yogurt is a fermented dairy product similar to curd, which is also showed anticancer activity because of the presence of linoleic acid (Urbanska, Paul, Bhathena, & Prakash, ). The probiotic bacteria present in the yogurt is also responsible for the anticancer activity (Tarrah et al, ). The mechanism involved in the suppression of tumorigenic activity is the enhancement of the immune system followed by the production of cytokines like tumor necrosis factor (TNFα) (LeBlanc & Perdigon, ).…”

Quality of Goat Milk Cheese with Addition of Rice Bran oil Ripened Using Lactobacillus casei and Streptococcus thermophilus

“…Therefore, the cheese in this study could be potentially classified as probiotic food. According to Tarrah et al (2018), two strains of S. thermophilus from dairy environment in Italy, namely M17PTZA496 and TH982 possess probiotic activity in vitro, although many S. thermophilus strain have very serious problem when passage through the human gastrointestinal tract. While, strain of Lactobacillus casei FNCC 0090 have been known as probiotic (Suseno et al, 2000;Aini and Hariani, 2019).…”