Phytochemical Profiling, Spectroscopic Characterization, and Antimicrobial Activity of Solvent Extracts of Imperata Cylindrica

Source abstract

Medicinal plants continue to serve as an important source of bioactive compounds with therapeutic potential. This study investigated the phytochemical composition, antimicrobial activity, and spectroscopic characterization of extracts obtained from the leaves and roots of Imperata cylindrica. Qualitative phytochemical screening revealed the presence of alkaloids, flavonoids, tannins, saponins, terpenoids, steroids, and glycosides. Quantitative analysis indicated that terpenoids (43.3%) and flavonoids (10.3%) were the dominant phytochemical constituents. Antimicrobial evaluation of aqueous, methanolic, and ethyl acetate extracts demonstrated significant inhibitory activity against pathogenic bacteria including Escherichia coli, Pseudomonas aeruginosa, and Staphylococcus epidermidis, with inhibition zones ranging from 3.05 ± 0.12 mm to 20.00 ± 0.55 mm. Antifungal activity was also observed against fungal pathogens such as Candida albicans and Aspergillus niger. Minimum inhibitory concentrations ranged from 0.2 to 0.8 mg/mL. Fourier Transform Infrared (FTIR) spectroscopy revealed the presence of functional groups including hydroxyl, carbonyl, and aromatic structures associated with phenolic and terpenoid compounds. UV–Visible spectroscopy indicated electronic transitions characteristic of conjugated organic molecules. GC–MS analysis identified several bioactive constituents including fatty acid derivatives, phenolic compounds, and terpenoid molecules, which may contribute to the observed antimicrobial activity. The findings provide scientific evidence supporting the traditional medicinal use of Imperata cylindrica and highlight its potential as a source of natural antimicrobial agents for pharmaceutical applications.