Inhibitory effect of lactic acid bacteria on the mutagenicity of nitrosamine

• Main Authors: Hsiao-Cheng Chen, 陳曉錚
• Other Authors: 丘志威
• Format: Others
• Language: zh-TW
• Published: 2002
• Online Access: http://ndltd.ncl.edu.tw/handle/09895577179149273711

碩士 === 輔仁大學 === 食品營養學系 === 91 === The objectivess of this study were to investigate (1) the mutagenicity of various concentrations of nitrosamines and different lactic acid bacteria, (2) the antimutagenicity of lactic acid bacteria concentrations and filtrates obtained from cell suspensions of lactic acid bacteria against nitrosamines, (3) the antimutagenic activity of commercial yogurt containing lactic acid bacteria against nitrosamines. The mutagenic activites of three N-nitrosamines were tested using Salmonella typhimurium TA98 and TA100. N-nitrosamine was not mutagenic to TA98 when the concentrations were below 10 mg/plate. N-nitrosodimethylamine (NDMA) and N-nitroso- diethylamine (NDEA) also showed no mutagenicity to TA100 when the concentrations were below 5 mg/plate. However, the mutagenicity of N-nitrosopyrrolidine (NPYR) in the presence of S9 mix with increasing concentration in the range of 0.5~5 mg per plate. In all of the selected 5 strains, Lactobacillus spp., Bifidobacterium longum CCRC14634, and Streptococcus thermophilus CCRC14087 were not mutagenic to TA100, and the pH had no effect. All of the lactic acid bacterial growth broths examined moderately inhibited the mutagenicity of NPYR (4 mg/plate). Lactobacillus casei CCRC14073 showed the highest inhibition of 54.4%, and the mutagenicity of NPYR was inhibited to a smaller extent by each culture of L. bulgaricus CCRC14007, B. longum CCRC14634 and Lactobacillus acidophilus CCRC10695. Most supernatant of lactic acid bacterial growth broths tested had no antimutagenic effect against NPYR, whereas L. casei CCRC14073 showed weak antimutagenic activity. Lactic acid bacterial cells when presence at concentration of 109 CFU/mL showed higher antimutagenic activity against NPYR. Among the strains examined, L. casei CCRC14073, L. bulgaricus CCRC14007, B. longum CCRC14634 and S. thermophilus CCRC14087 exhibited higher inhibition percentage from 16.7 to 26.3%. In contrast, L. acidophilus CCRC10695 did not show appreciable levels of inhibition. In addition, some commercial yogurts containing viable lactic acid bacteria showed inhibitory effects in the range of 19.1~29.7% as well against the mutagenicity of NPYR