Phytochemical screening, Lc–Ms profiling and antimicrobial activity of Cassia Occidentalis root extract against selected clinical Pathogenss

Abstract

Cassia occidentalis is a medicinal plant widely used in traditional medicine for the treatment of infections, fever, inflammation, and gastrointestinal disorders. This study investigated the phytochemical composition, LC–MS profile, and antimicrobial activity of the ethanolic root extract of C. occidentalis. Fresh roots were collected, authenticated, shade-dried, pulverized, and extracted by cold maceration with ethanol. Preliminary phytochemical screening was carried out using standard qualitative methods, while chemical constituents were characterized by liquid chromatography–mass spectrometry (LC–MS). Antimicrobial activity was evaluated against selected clinical pathogens using agar well diffusion and broth dilution assays. Phytochemical analysis revealed the presence of tannins, flavonoids, saponins, phenols, terpenoids, and alkaloids, whereas steroids were absent. The extraction yield was 2.5%, corresponding to approximately 34.0 mg mL⁻¹ of crude extract. LC–MS profiling revealed several putatively bioactive compounds, including taxifolin, reserpine-like alkaloid derivatives, 6''-O-p-coumaroyltrifolin, 6-hydroxynicotinic acid, and aloe-emodin. These metabolites belong to pharmacologically important classes such as flavanonols, flavonoid glycosides, alkaloids, pyridine derivatives, and anthraquinones, which are associated with antioxidant, anti-inflammatory, antimicrobial, hepatoprotective, and anticancer activities. The extract demonstrated inhibitory activity against the tested pathogens in both diffusion and dilution assays, indicating appreciable antimicrobial potential. The observed activity may be attributed to the synergistic effects of flavonoids, phenolic compounds, alkaloids, and anthraquinone-related metabolites identified in the extract. These findings provide scientific support for the traditional use of C. occidentalis roots and highlight their potential as a source of bioactive compounds for antimicrobial drug discovery and pharmaceutical applications.