转基因玉米对大鼠肠道菌群的影响研究

Impact of consumption of transgenic corn on gut flora in SD rats

目的观察食用转基因玉米对SD大鼠肠道常见菌群的影响。方法将断乳的SD大鼠随机分为4组:转基因玉米1组(T1)、转基因玉米2组(T2)、非转基因玉米组(N)和阴性对照组(C)。T1和T2组饲料中分别含76.1%和76.4%的转基因玉米,N组饲料中含74.9%的非转基因玉米。喂养大鼠70 d,每周称大鼠体重1次,每周称2次进食量。收集实验开始前后的粪便样品并检测肠道菌群。结果与C组相比,T1、T2和N组进食量均增加,但各组体重及体重增值与C组相比均无统计学意义。T1、T2组与C组和N组相比肠球菌、双歧杆菌、乳杆菌、肠球菌、类杆菌、梭菌和酵母样真菌数均无统计学意义,T2组喂饲前肠杆菌比C组低,喂饲后比喂饲前升高(P<0.05),但各组间比较均无统计学意义。结论用转基因玉米喂养SD大鼠70 d未发现其对肠道菌群组成有显著影响。

Objective To observe the impact of consumption of the transgenic corn on the gut flora in SD rats. Methods Weaned SD rats were randomly divided into four groups ： transgenic corn group 1 （ T1 ）, transgenic corn group 2 （ T2）, non-transgenie corn group and negative control group（C）. The diet of T1 and T2 groups contained 76. 1% and 76.4% transgenic corn, respectively. The diet of N group contained 74. 9% non-transgenic corn. The diet formula of C group was AIN93G. The macro-and micro-nutrient content were equal in three diets. The rats were fed for 70 days. Food intakes were weighed twice every week ; body-weight was measured every week. Feces samples were collected before and after the feeding period and the diversity of the gut flora were determined. Results The feed intakes were significantly higher in the groups that contain either transgenic or nontransgenic corns but the body weight and weight gain in each group were not significantly different from each other after 70 days. There were no significant differences among the four groups in the numbers of the major gut bacterial communities（ P 〉 0. 05 ） except that the amount of enterobacter spp in the T2 group increased after 70 days when compared with the baseline level, but the increment cannot be attributed to the corn consumed because the baseline level of enterobacter spp was lower in the T2 than the C group. Conclusion From the results of the current experiment no adverse effects of the consumption of the transgenic corn on gut flora can be confirmed.