Antimutagenic Activity of the Milk Fermented by Mixed-Cultured with Various Lactic Acid Bacteria and a Yeast.

The fermented milk produced with lactic acid bacteria is reported to possess anticarcinogenic or antimutagenic activities1)2). HOSODA et al. examined the antimutagenic effects of the milks cultured individually using 71 strains and 76 strains of lactic acid bacteria on the utagenicities of N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) and 3-amino-1-methyl-5H-pyrido (3, 4-b) indol (Trp P-2), respectively, and showed that each strain displayed its characteristic antimutagenic effect of the respective mutagens3)4). Kefir is known as an aged fermented milk product. The longevity of the people in the Cocasass region is postulated to be in part due to the comsumption of the fermented milk. Kefir is produced by Kefir granule in which various species of lactic acid bacteria, yeasts, and some species of acetic acid bacteria coexist5). This prompted us to speculate that the fermented milk produced by the mixture of various species of lactic acid bacteria and other species of microbe might contain a wider variety of physiological substances, compared to the milk cultured with a single strain of lactic acid bacteria. Based on this idea, we attempted to prepare the aged-fermented milk with mixtures of various lactic acid bacteria and a yeast, and examined the antimutagenic activities toward various mutagens.