Regulatory Effects of Green Tea Polyphenols on the Gut Bacteriophages: An in Vitro Study

Abstract

The human gastrointestinal tract hosts a diverse microecological environment, where the gut virome is crucial for maintaining health. Although the effects of green tea polyphenols (GTP) on intestinal flora have been acknowledged, it's unclear whether their primary impact is on gut phages or bacteria. This study investigated the morphology and pH sensitivity of major gut phages and examined how GTP affect these phages and their host bacteria. The research found that E. faecalis phage belongs to the Siphoviridae family within the Caudovirales, while E. cloacae, Citrobacter, and E. coli T4 bacteriophages fall under the Myoviridae. The optimal MOI were determined for each phage: 0.01 for E. faecalis phage, 1 for E. cloacae phage, 1 for Citrobacter phage, and 0.1 E. coli. The study revealed the E. faecalis phage remained stable within pH 6.0 to 10.0, whereas the other three phages maintain stability from pH 4.0 to 10.0. The GTP concentration of 1.0 mg/mL effectively inhibited the gut phages of the four host bacteria without impacting their bacteria. This study highlighted the interaction between GTP and gut virome, underscoring its importance for human health. It also sets the stage for further research into how GTP regulated gut microbiota, focusing on phages.

Keywords: tea polyphenol, gut phage, gut bacteria, MOI, pH