Qualitative Phytochemical Screening of Citrullus colocynthis (L.) Schrad. and Diplocyclos palmatus (L.) C. Jeffre

Abstract

Medicinal plants are an important source of naturally occurring phytochemicals that contribute to their therapeutic properties. The present study was undertaken to investigate the qualitative phytochemical constituents of Citrullus colocynthis (L.) Schrad. and Diplocyclos palmatus (L.) C. Jeffrey using petroleum ether, chloroform, and methanol extracts. Preliminary phytochemical screening was performed using standard qualitative chemical tests for alkaloids, flavonoids, phenolic compounds, tannins, saponins, diterpenes, triterpenoids, glycosides, steroids, and anthraquinones. The results demonstrated the presence of several classes of secondary metabolites in both investigated plants, with variation according to the extraction solvent. In C. colocynthis, alkaloids, flavonoids, tannins, diterpenes, triterpenoids, glycosides, and steroids were detected in the three extracts, whereas phenolic compounds and saponins were detected mainly in chloroform and methanol extracts. Anthraquinones were not detected. In D. palmatus, chloroform and methanol extracts showed a comparatively broad phytochemical profile containing alkaloids, flavonoids, tannins, saponins, diterpenes, triterpenoids, glycosides, and steroids. Phenolic compounds were detected in the methanol extract, while the petroleum ether extract showed tannins, triterpenoids, glycosides, and steroids. Anthraquinones were absent from all extracts of both plants. The findings demonstrate solvent-dependent extraction of diverse phytoconstituents and provide preliminary evidence supporting further chromatographic and quantitative investigation of these medicinal plants.

Keywords: Citrullus colocynthis; Diplocyclos palmatus; phytochemical screening; secondary metabolites; qualitative analysis; medicinal plants