Goldin B R, Swenson L, Dwyer J, Sexton M, Gorbach S L
J Natl Cancer Inst. 1980 Feb;64(2):255-61. doi: 10.1093/jnci/64.2.255.
The effect of diet and Lactobacillus acidophilus supplements on fecal microflora enzyme activity was studied in humans. The bacterial enzymes that were investigated are known to catalyze reactions that may result in formation of proximal carcinogens. Compared to vegetarians, omnivores eating a "Western-type" diet had higher levels of beta-glucuronidase, nitroreductase, azoreductase, and steroid 7-alpha-dehydroxylase in their fecal microflora. Removal of red meat or addition of fiber in the form of bran or wheat germ to the diet of omnivores for 30 days had no effect on beta-glucuronidase, nitroreductase, or azoreductase activity. However, removal of red meat or addition of fiber reduced fecal steroid 7-alpha-dehydroxylase activity. The addition of viable Lactobacillus acidophilus supplements to the diet of omnivores significantly decreased fecal bacterial beta-glucuronidase and nitroreductase activities. Thirty days after Lactobacillus supplements were curtailed, fecal enzyme levels returned to normal base-line activities. These findings suggested that the metabolic activity of the fecal microflora was influenced by diet and could be altered by Lactobacillus supplements and to a lesser extent by dietary fiber.
在人体中研究了饮食和嗜酸乳杆菌补充剂对粪便微生物群酶活性的影响。所研究的细菌酶已知可催化可能导致近端致癌物形成的反应。与素食者相比，食用“西式”饮食的杂食者粪便微生物群中的β-葡萄糖醛酸酶、硝基还原酶、偶氮还原酶和类固醇7-α-脱羟基酶水平更高。在杂食者的饮食中去除红肉或添加麸皮或麦芽形式的纤维30天，对β-葡萄糖醛酸酶、硝基还原酶或偶氮还原酶活性没有影响。然而，去除红肉或添加纤维可降低粪便类固醇7-α-脱羟基酶活性。向杂食者的饮食中添加活的嗜酸乳杆菌补充剂可显著降低粪便细菌β-葡萄糖醛酸酶和硝基还原酶活性。停止补充乳杆菌30天后，粪便酶水平恢复到正常基线活性。这些发现表明，粪便微生物群的代谢活性受饮食影响，可通过补充乳杆菌改变，在较小程度上也可通过膳食纤维改变。
