Metabolism of the nitrofurans. III. Studies with xanthine oxidase in vitro.

For a better understanding of the mechanism of action of the nitrofurans in the mammalian organism, studies of their metabolism have been initiated. Excretion studies (1) have revealed that only a small part of most ingested nitrofurans appears unchanged in the urine. Bender and Paul (2) in preliminary studies have shown that 5-nitro-2-furaldehyde semicarbazone (Furacin’) undergoes degradation in the presence of various body tissues in vitro and point to possibilities that may include a Furacin-xanthine oxidase relationship in viva. That the xanthme oxidase-hypoxanthine system could reduce the nitro group of nitrophenols was shown by Greville and Stern (3), but no reduction products were isolated. Bueding and Jolliffe (4) in their study of trinitrotoluene in vitro found that the xanthine oxidase-hypoxanthine system reduced only one of the nitro groups to form hydroxylaminodinitrotoluene. The reduction to aminodinitrotoluene was accomplished in vitro with tissue slices and extracts. The metabolic studies of the nitrofurans have been extended to the determination of the mutual effects of xanthine oxidase systems and the nitrofurans. Data will be presented in this paper on the effect of Furacin on the xanthine oxidase-hypoxanthine system and the destruction of Furatin and other nitrofurans by this system under anaerobic conditions.