Background and Objectives: Fermented seeds of Parkia biglobosa or “African mustard” are widely consumed in Togo. These fermented seeds are known to have a protective effect against the occurrence of cardiovascular diseases. The objective of the present study is to evaluate the effect of the decoction of fermented seeds on cardiovascular system.
 Methods: The fermented seeds have been subjected to physicochemical tests. A decoction was prepared and underwent qualitative and quantitative phytochemical tests. The decoction was also administered intravenously to rabbits at cumulative doses (17.5 mg / kg; 35 mg / kg; 70 mg / kg and 140 mg / kg) to assess the effect of Parkia biglobosa fermented seeds on the cardiovascular system. Parameters such as blood pressure, heart rate, and electrocardiogram (ECG) were then recorded.
 Results: The fermented seeds had a water content of 8.1 ± 0.2%, the total ash content was 21 ± 0.4% and the content of ash insoluble in hydrochloric acid of 2.3 ± 0.1%. The extract contained alkaloids, cardiac glycosides (with a content of 13.9 ± 0.2 µg equivalent of Digoxin / mg of extract) and saponins. The decoction causes a dose-dependent hypotension and bradycardia at 140mg / kg. The ECG shows a decrease of the amplitude of QRS complex at doses of 70 mg / kg and 140 mg / kg.
 Conclusion: The decoction has a dose-dependent hypotensive effect probably linked to its cardiotonic glycosides.