INHIBITION OF BENZO[A]PYRENE-INDUCED MOUSE FORESTOMACH NEOPLASIA AND REDUCTION OF H2O2 CONCENTRATION IN HUMAN POLYMORPHONUCLEAR LEUKOCYTES BY FLAVOR COMPONENTS OF JAPANESE-STYLE FERMENTED SOY-SAUCE

Previously it was reported that 4-hydroxy-2 (or 5)-ethyl-5 (or 2)-meth yl-3(2H)-furanone (HEMF), a characteristic flavour component of Japane se-style fermented soy sauce that exhibits antioxidant activity, inhib its benzo[a]pyrene-induced forestomach neoplasia in mice. The antioxid ant and anticarcinogenic activities of other structurally similar soy sauce flavour components are now reported. 4-Hydroxy-5-methyl-3(2H)-fu ranone (HMF) and 4-hydroxy-2,5-dimethyl-3(2H)-furanone (HDMF) were fou nd to be antioxidants. In particular, HMF and HDMF (as well as HEMF) r educed hydrogen peroxide concentration in human polymorphonuclear leuc ocytes stimulated by arachidonic acid or 12-O-tetradecanoylphorbol-13- acetate. HMF and HDMF were administered individually in semipurified d iet to female ICR mice previously treated with benzo[a]pyrene (1.5 mg/ wk, orally for 4 wk) to initiate forestomach neoplasia. The mice were killed at 30 wk of age. Both furanones reduced forestomach neoplasms, with HDMF exhibiting more potency. The data indicate that HDMF and HMF , like HEMF, inhibit carcinogenesis in this system by acting at the po st-initiation stage. (C) 1997 Elsevier Science Ltd.