Dosage Determination of Ethnopharmacologically Used Fermented Zea mays subsp. mays Liquor Extract of Bambusa vulgaris Schrad. Ex. J.C. Wendel Leaf Against Salmonella typhi

Background: Bambusa vulgaris (bamboo) is a common plant in tropical regions of the world, with multiple biological activities. Cereal steep liquors have been identified to act against some fecal bacteria. Given the increasing prevalence of antimicrobial resistance coupled with the cost of antibiotics, there is a need for mitigation efforts and the shift by locals to herbal products. Methods: The factorial study design was employed. Bamboo leaves were washed, dried, milled, and soxhlet extracted for 16 h using the steep fermented liquor from Zea mays subsp. mays as the solvent. Rotary evaporated extracts of various weights were used to carry out sensitivity and minimum inhibitory concentration (MIC) tests. Oral acute toxicity was determined. The in vivo assay was used to determine the effective dosage for the treatment of infected mice while distilled water and ciprofloxacin served as negative and positive controls, respectively. Results: The average inhibition zone diameters in the sensitivity test at 25, 50, and 100 mg/mL concentrations were 16.20 ± 0.06 mm, 19.10 ± 0.02 mm, and 22.10 ± 0.05 mm, respectively, while the MIC against Salmonella typhi was 25 mg/mL. The extract was found to be safe at up to 5000 mg/kg dose, which means that the LD50 was ≥ 3808 mg/kg. The Widal test revealed that mice responded to treatment with the extract at different concentrations (50, 100, and 200 mg/mL) as the number of days increased. The in vivo assay on day 14 showed the bactericidal property at a dosage of 200 mg/mL. Conclusions: Bamboo leaves extract in steep liquor from fermented yellow maize displayed excellent pharmacological activity against the pathogenic organism of typhoid fever with a potential source of active agents.