s (µM) by adult human gut microbiota.    Comp.               Control   H0       H0       H0       H0       H0       H0       H0       H0       H0       H00      H00      H00      H00      H00   ------------------- --------- -------- -------- -------- -------- -------- -------- -------- -------- -------- -------- -------- -------- -------- --------   **