Effect of Genetically Modified Rice on Some Intestinal Microbial Flora in Rats

Background and purpose: Transgenic rice is a type of rice that its genetic sequence has been changed to improve its quantity and quality. Bt (Bacillus thuringiensis) transgenic rice expresses Cry1Ab protein and is named Tarom Molaii. There are no studies on the effect of this type of transgenic rice on gastrointestinal health in Iran, so, this study investigated the effect of Tarom Molaii transgenic rice on common microbial flora of rat intestine. Materials and methods: In this experimental study, 24 Sprague Dawley (SD) rats received transgenic and non-transgenic rice in their diets for 90 days and were compared with the control group that received standard rat diet. The number of Escherichia coli, Bifidobacterium, Lactobacillus, and Enterococcus bacteria and the total number of aerobic and anaerobic bacteria in fecal samples were examined in jejunum, ileum, and duodenum samples on days 60, 90, and after killing the rats. Results: The study showed that except for the total number of anaerobic bacteria in the stool sample on day 90, there was no significant relationship between the study groups and the number of bacteria (P>0.05). There was an increase in the number of intestinal Lactobacillus in the transgenic rice-fed group and a decrease in the number of anaerobic bacteria in the transgenic rice-fed group compared with the control group and the non-transgenic rice-fed group. Conclusion: Consumption of transgenic rice in current study had no considerable effect on the number of common bacteria in the intestinal normal flora. But, long-term studies are needed in other laboratory animals.