A total of 10 pathways were significantly enriched in ileal samples (Caprolactam_degradation, Glutathione_metabolism, Benzoate_degradation, Cytochrome_P450, Drug_metabolism___cytochrome_P450, Metabolism_of_xenobiotics_by_cytochrome_P450, Alzheimer_disease, Parkinson_disease, Cardiac_muscle_contraction, Apoptosis), while 3 were more enriched in cecal samples (Methane_metabolism, Epithelial_cell_signaling_in_Helicobacter_pylori_infection, Germination), and 2 were more enriched in jejunal samples (Tyrosine_metabolism, Chloroalkane_and_chloroalkene_degradation. Here, CYP2B6 is linked to Parkinsonism.