The objective of this study is determine the effect of Eleusinecoracana seed extract on gastrointestinal tract (GIT) microbiome of Wistar rat induced with tramadol. Twenty (20) healthy Wistar albino rats were weighed and allowed to acclimatize for one week with free access to food pallets and water and libitum. They were grouped into three (3) groups of four (4) rats each as group T1, T2 and control. Group T1 and T2 were administered with 0.1 and 0.2 g of the ethanolic extract respectively, while control were given distilled water. The study shows an increase in the weight of Wistar rat administered with high dosage of the plant extract when compared to those administered with low dosage of the extract and also the control group. Different microbial isolates isolated from the fecal and GIT of Wistar rats include; Aeromonashydrophyla, Proteus spp., Pseudomonasaeruginosa, Citrobacterfreundii, S. spp., Staphylococcusaureus, C. freundii, and Providencia spp. The study revealed that the negative control group contains Pseudomonas aeruginosa with percentage incidence of 28.1%, followed by A. hydrophyla and Proteus spp., with percentage incidence of 25 and 21.9% respectively, while Citrobacterfreundii has the lowest percentage incidence of 3.1%. While positive group and group administered with the plant extract had Providenciaspp as the only organisms present with percentage incidence of 100%.From the study, it was revealed that the extract of finger millet have effect on the microbiome of the GIT with a reduction in the population of bacteria colonies. The population of the bacterial colonies were reduced drastically on administration of the plant extract and tramadol.

Keywords : Gastrointestinal tract, colony count, finger millet, antimicrobial.