Preliminary Phytochemical Screening and Antimicrobial Activity of the Hydroethanolic Extract of the Fruits of Solanum torvum (Swartz) (Solanaceae) Use as Vegetable in Togo

The fruits of Solanum torvum (Swartz), a vegetable-fruit, are used in traditional medicine in Togo in the treatment of infectious diseases and as an anti-anemic. This study then focused on the antimicrobial activity assessment of the hydroethanolic extract of these fruits in the interest of contributing to the valorization of this Togolese flora’s species. A hydroethanolic extraction (50 % - 50 %: v/v) was performed followed by preliminary phytochemical tests. Antimicrobial activity was determined on fourteen bacterial strains using the agar diffusion method. Qualitative phytochemical screening revealed the presence of alkaloids, reducing compounds, tannins, cardiac glycosides, flavonoids, coumarins, triterpenes, saponins, total carbohydrates and free quinones. The extract was active on the reference strains of S. aureus, E. coli, S. pneumoniae and P. aeruginosa. However, this activity was only observed on clinical strains of S. pneumoniae and P. aeruginosa. The extract showed MICs of 25 and 50 mg/ml and BMCs of 50 and 100 mg/ml respectively for S. pneumoniae and P. aeruginosa. The MBC/MIC ratio for these two strains was 2. These fruits would then have bacteriostatic activity on S. pneumoniae and P. aeruginosa. The antibacterial properties of the extract on these germs could justify the use of this plant in traditional medicine for the treatment of certain bacterial infections. Keywords: Solanum torvum, fruits, phytochemical compounds, antimicrobial activity