Evaluation of Diuretic Activity and Phytochemical Contents of Aqueous Extract of the Shoot Apex of Podocarpus falcactus

Abstract

Background

In Ethiopian folk medicine Podocarpus falcactus is used to treat stomachache, cancer, diabetes, and difficulty of urination. However, its diuretic activity has not been proven scientifically.

Objective

To determine the diuretic activity and phytochemical contents of the aqueous extract of the shoot apexes of Podocarpus falcactus.

Methods

The coarse powder of Podocarpus falcactus shoot apex was extracted by cold maceration using distilled water. Male rats were treated with distilled water, the standard drug (furosemide 10 mg/kg), and three different doses (100, 200, and 400 mg/kg) of the aqueous extract. The diuretic activity was determined by measuring parameters such as time to the first urination, volume, electrolyte concentration, and pH of urine. Electrolyte indices were calculated to elucidate the possible mechanism of diuresis. Additionally, qualitative and quantitative determination of phytochemicals in the plant extract was carried out.

Results

The aqueous extract induced diuresis, natriuresis, and kaliuresis in a dose- and time-dependent manner as compared to the negative control. The extract at 200 and 400 mg/kg doses produced significant diuresis (p<0.001) by the end of the fifth hour compared to the negative control. Excretion of sodium, potassium, and chloride also significantly (p<0.001) increased following extract administration. In addition, there was a significant change in the pH of urine samples of the extract-treated group compared with the negative control. Qualitative and quantitative determination of phytochemicals revealed the presence of alkaloids, flavonoids, phenolics, and tannins with the value of 128.4 mg atropine equivalents (AE)/g, 142.23 mg quercetin equivalents (QE)/g, 196.84 mg gallic acid equivalents (GAE)/g, and 25.5 mg tannic acid equivalents (TAE)/g, respectively. The aqueous extract exhibited significant diuretic activity due to its phytochemical content, which could be used as a starting point for further studies.

Conclusion

The aqueous extract showed significant diuretic activity and confirmed the folkloric use of Podocarpus falcactus.

Keywords:

• alkaloids
• flavonoids
• phenolics
• Podocarpus falcactus
• rats
• saluretic
• tannins

Data Sharing Statement

All the necessary data and materials can be obtained from the corresponding author with a reasonable request.

Ethics Approval

The study was approved by the Ethical Review Board of the College of Medicine and Health Sciences of Wollo University.

Author Contributions

All authors made a significant contribution to the conception and design of the study, execution, acquisition, analysis, and interpretation of data. Besides, they took part in drafting, revising, or critically reviewing the article, gave final approval of the version to be published, have agreed on the journal to which the article has been submitted, and agree to be accountable for all aspects of the work. The authors have consented to the publication of this manuscript.

Disclosure

The authors report no conflicts of interest for this work.

Additional information

Funding

No funding was received for this work.