In vitro inhibition of fecal bacterial isolates by sterols. Shown are optical density differences between micelles containing cholesterol, cholesteryl-linoleate, β-sitosterol, and stigmastanol compared to control micelles without sterols for the gut bacterial isolates Lactobacillus reuteri (A), Collinsella aerofaciens (B), and Clostridium histolyticum (C). ΔOD600, change in optical density at 600 nm.