Diuretic activity of hydro-alcoholic extract and solvent fractions of Solanum lycopersicum L. leaves in mice

Solanum lycopersicum L. has long been used to promote diuresis in Ethiopia. Although strong ethnobotanical evidence is available, its diuretic activity has not been scientifically proven. The aim of this study was to provide scientific evidence supporting the traditional use of S. lycopersicum L. leaves as a diuretic. The leaves of S. lycopersicum L. were extracted using a maceration technique with 80% methanol. The 80% hydro-methanol extract and solvent fractions (ethyl acetate, n-hexane, and aqueous) were administered orally to the mice at doses of 100, 200, and 400 mg/kg. The effects of these extracts and solvent fractions were compared over 5 h's period with a negative control and a standard medication (furosemide, 10 mg/kg). The extract at a dosage of 2000 mg/kg was shown to be safe in the acute oral toxicity test. The 400 mg/kg hydro-methanol extract of S. lycopersicum L. leaves showed a significant (p < 0.001) increase in both urine volume and sodium excretion compared to the negative control. The 400 mg/kg aqueous solvent fraction and the standard drug (furosemide 10 mg/kg) showed significant (p < 0.001) increases in both urine volume and sodium excretion compared to the negative control. The 400 mg hydro-methanol extract and 400 mg aqueous solvent fraction of S. lycopersicum L. leaves showed urine and salt excretion profiles comparable to those of the standard drug. The results of this study reveal that 80% hydro-methanol extract and the solvent fraction of the leaves of S. lycopersicum L. demonstrate a diuretic effect and validate traditional assertions.