Phytochemical Profiling and Antimicrobial Activity of Methanol Leaf Extract of <i>Sida acuta</i> against Foodborne Pathogens

Abstract

Foodborne diseases remain a significant global public health concern, largely driven by contamination with pathogenic bacteria and fungi. This study investigated the phytochemical profile and antimicrobial activity of the methanol leaf extract of Sida acuta against selected foodborne pathogens. Phytochemical constituents were characterized using standard qualitative and quantitative analytical methods, while antimicrobial activity was assessed in vitro using the agar well diffusion technique. Minimum inhibitory concentration (MIC) and minimum bactericidal/fungicidal concentration (MBC/MFC) were determined using broth dilution assays. Quantitative phytochemical analysis revealed high levels of phenolic compounds (257.40 ± 0.11), tannins (130.51 ± 0.21), saponins (115.02 ± 0.37), flavonoids (96.45 ± 0.33), and alkaloids (27.41 ± 0.12). The extract exhibited dose-dependent antimicrobial activity against Staphylococcus aureus, Escherichia coli, Salmonella Typhi, and Aspergillus fumigatus. At the highest tested concentration (200 mg/mL), inhibition zones measured 25.00 ± 0.58 mm, 18.00 ± 1.15 mm, 15.33 ± 0.33 mm, and 27.67 ± 2.21 mm, respectively. These findings demonstrate that Sida acuta is a rich source of bioactive phytochemicals with broad-spectrum antimicrobial activity, highlighting its potential as a candidate for the development of novel, plant-based antimicrobial agents for controlling foodborne pathogens. Further studies are warranted to isolate and characterize the active compounds and evaluate their mechanisms of action.