Preliminary pharmacognostic and diuretic evaluation of crude aqueous extract of Monodora myristica (Gaertn.) dunal (Annonaceae) seeds on albino rats

Abstract

Diuretics are part of therapeutic strategies to control fluid overload manifesting as ankle swelling, ascites, pulmonary edema as well as  renal and cardiovascular disorders. This study aims to ascertain the diuretic potentials of crude aqueous extract of Monodora myristica  seeds in normal male albino rats. A 700 g quantity of the powdered seeds sample of Monodora myristica was extracted by maceration  using distilled water. Phytochemical and chemo-microscopic analyses were carried out using standard procedures. The male albino rats  were divided into five groups of six animals each. The control group received distilled water (10 mL/kg), the reference group received  furosemide (25 mg/kg) and the test groups were administered different doses of the crude aqueous extract doses (125 mg/kg, 250 mg/ kg, and 500 mg/kg) by oral route, respectively. The urine volume (mL) was obtained at the 5th hour and 24th hour. The electrolyte concentration (Na+, K+ and Cl-), urinalysis, urea and creatinine were measured to establish the extract’s diuretic activity. The obtained  urine samples were analyzed for urinary excretion and diuretic action. The electrolyte indices were calculated to identify either the  natriuretic, saliuretic or carbonic anhydrase inhibitor activity of the extract. The result of the preliminary phytochemical analysis showed  the presence of saponins, tannins, flavonoids, terpenoids, alkaloids, sterols and phenol, while cardiac glycosides and reducing sugar were  absent in the crude aqueous extract of Monodora myristica seeds. The quantitative phytochemical analysis of crude aqueous  extract shows the quantity of the phenol, flavonoid and alkaloid which were 9.07±0.35 mg gallic acid equivalents (GAE)/g, 332.70±14.62  mg quercetin equivalents (QE)/g, 12.35±0.55 mg atropine equivalents (AE)/g respectively. The chemo-microscopy evaluation revealed the  presence of lignin, starch, mucilage, cellulose and calcium oxalate. Acute toxicity study showed that the extract is safe and no toxic effects  were observed among the albino rats even at a higher dose of 5000 mg/kg. The study revealed an increase in the body weight of  the animals administered furosemide at a dose of 25 mg/kg (190.17±6.86 g) when compared with those of the control groups treated  with the only vehicle at a dose of 10 mL/kg (179.83±9.13 g). Diuretic effect was observed in the treated groups in a dose-dependent  manner. The aqueous extract exhibited diuretic activity possibly due to its phytochemical contents, which could be used as a starting  point for further studies. Conclusively, findings from our study show that crude aqueous extract of Monodora myristica seeds possess  diuretic and natriuretic activities as compared to the standard drug (Furosemide). However, further research work needs to be carried   out to justify this claim.