Fig. 2

Blastocystis inhibition of B. longum is linked to an increase in cellular ROS. B. longum exhibited lower colony-forming unit per milliliter when incubated with E. coli for 24 h at 37 °C in PBS. The count is even lower in the presence of Blastocystis (a). There is an increase in some oxidoreductase genes in B. longum when it is incubated with E. coli and Blastocystis indicating that the bacterium is under oxidative stress (b). Flow cytometry analysis shows B. longum cells’ shift to the right indicating more cells have cellular ROS content when co-incubated with E. coli, Blastocystis, or both (c). Blastocystis caused a greater increase in ROS content compared to E. coli (d). *p < 0.05; **p < 0.01; ***p < 0.001