Wise A, Rowland I R, Mallett A K
Food Chem Toxicol. 1984 Feb;22(2):113-7. doi: 10.1016/0278-6915(84)90090-5.
Weanling or adult (9 wk old) rats were fed diets containing 0, 250 or 500 g lactose/kg for 10 days, after which the activities of six caecal microbial enzymes (azoreductase, beta-glucosidase, beta-glucuronidase, nitrate reductase, nitroreductase and urease) were determined. Adult controls had larger caeca than weanlings, but the numbers of bacteria were not significantly different. Expressed in relation to body weight, caecal microbial enzyme activities were significantly lower in adult controls, with the exceptions of beta-glucuronidase and urease. Lactose caused caecal enlargement; this was greatest in weanling animals, which also showed a decreased concentration of bacteria. Lactose increased total nitrate reductase and urease activities in both age groups, but decreased total azoreductase and nitroreductase activities in weanlings. Enzyme activities per 10(9) bacteria were decreased for azoreductase, beta-glucosidase, beta-glucuronidase and nitroreductase in both age groups, while urease activity increased. Azoreductase and nitroreductase activities were highly correlated but nitrate reductase and urease did not correlate significantly with any other enzyme activity.
将断奶或成年（9周龄）大鼠喂食含0、250或500克乳糖/千克的日粮10天，之后测定六种盲肠微生物酶（偶氮还原酶、β-葡萄糖苷酶、β-葡萄糖醛酸酶、硝酸盐还原酶、硝基还原酶和脲酶）的活性。成年对照组的盲肠比断奶大鼠的大，但细菌数量无显著差异。以体重计，成年对照组的盲肠微生物酶活性显著较低，但β-葡萄糖醛酸酶和脲酶除外。乳糖导致盲肠增大；这在断奶动物中最为明显，其细菌浓度也降低。乳糖增加了两个年龄组的总硝酸盐还原酶和脲酶活性，但降低了断奶大鼠的总偶氮还原酶和硝基还原酶活性。两个年龄组中，每10⁹个细菌的偶氮还原酶、β-葡萄糖苷酶、β-葡萄糖醛酸酶和硝基还原酶的酶活性均降低，而脲酶活性增加。偶氮还原酶和硝基还原酶活性高度相关，但硝酸盐还原酶和脲酶与任何其他酶活性均无显著相关性。
