I try to analyze some additional files available, too. And especially I am curious on the coding found in one of them. Namely, in the file entitled „C18n_NN” (https://ibdmdb.org/tunnel/public/HMP2/Metabolites/1723/rawfiles), I see in column G: “SM-5Q4W7”, and in column H: “SM-5QVZ9”, etc. I suppose SM-5Q4W7 could be a code of an individual subject, but I am not able to confirm in the paper how to interpret that code in details. Knowing it, maybe I would catch more interesting knowledge for me with regards to some lipid metabolites and drugs shown in column F.