Nitroarenes (nitropolycyclic aromatic hydrocarbon: NPAH) are active mutagenic materials and are detected in toner,airborne particulates and exhaust gas from cars. The possibility for NPAH to be taken up into the body is extremely high because of their wide distribution in the environment. Therefore, the sorption of NPAH by dietary fiber in artificial gastric juice (AGJ) and artificial intestinal juice (AIJ) at 37℃ was examined. In our experiments, we used a solution of 1- nitropyrene (1-NP), 1,3-dinitropyrene (1,3-DNP), 1,6-dinitropyrene (1,6-DNP) and 1,8-dinitropyrene (1,8-DNP) as representative nitroarenes, and chitin, carboxymethyl cellulose (CMC), agar and insoluble dietary fiber from young barley leaves (YBL) as dietary fibers. NPAH was reduced by the semi-micro reduction method using sodium hydrosulfide, and the level of aminoarene was measured using HPLC.
　In the four-component NPAH solution, the amounts of NPAH sorbed by chitin, CMC, agar and YBL were 7.0～46.9％, 59.1～82.3％, 0％ and 69.9～100％, respectively in AGJ and 61.2～83.8％, 17.3～48.7％, 0～18.1％ and 89.7～100％, respectively in AIJ. Sorption of NPAH by chitin and CMC was affected by the pH of the sorbate, while the sorption by YBL was not affected by pH. The Freundlich and Langmuir equations were applied to the sorption isotherms of NPAH by chitin, CMC and YBL. The Freundlich equation fitted well the sorption isotherms of NPAH by chitin and CMC in AIJ, while the Langmuir equation fitted well the sorption isotherms of NPAH by YBL in AGJ and AIJ. Together, these results suggest that chitin and CMC are more useful than agar in the sorption of NPAH in AIJ and AGJ, respectively, and that YBL is the most effective sorbent of NPAH in both AGJ and AIJ.

Key words: nitroarenes, chitin, carboxymethyl cellulose, agar, insoluble dietary fiber from young barley leaves.