Disclosed is an adsorbent including a porous carbon material which is produced from a plant-derived material having a silicon (Si) content of not less than 5 wt.% and which has a value of specific surface area determined by the nitrogen BET method of not less than 10 m 2 /g, a silicon content of not more than 1 wt.%, and pore volumes determined by the BJH method and the MP method of not less than 0.1 cm 3 /g. The adsorbent adsorbs indole, uric acid, adenosine, ±-amylase, 3-methylindole, tryptophan, indicant, theophylline, inosine 5-monophosphate disodium salt, adenosine 5-triphosphate disodium salt, a fatty acid, a coloring matter, hydrophobic molecules, or an organic matter (for example, organic molecules or a protein) having a number average molecular weight of not less than 1 × 10 2 and less than 5 × 10 2 .
