EC Microbiology

The global rise of antimicrobial resistance (AMR) poses a critical threat to public health, necessitating the exploration of novel therapeutic strategies against multidrug-resistant (MDR) bacterial infections. This study investigated the inhibitory potential of Cyperus esculentus (tiger nut) extracts against selected MDR pathogens. Phytochemicals were extracted using the maceration method, and antibacterial activity was assessed via the agar well diffusion technique. Gas Chromatography-Mass Spectrometry (GC-MS) was employed for phytochemical profiling. Identified bioactive compounds were subjected to virtual screening against key bacterial target proteins-DNA gyrase B and penicillin-binding protein 2a-using the Maestro Schrödinger Suite (2021-2). In vitro results revealed that the ethanolic extract exhibited notable inhibitory effects, producing zones of inhibition measuring 18 mm and 17 mm against Escherichia coli and Staphylococcus aureus, respectively. GC-MS analysis identified several active compounds, including D,L-xylitol,1-O-dodecanoyl, L-lactic acid, β-monolaurin, and dodecanoic acid pentafluorophenyl ester. Among these, D,L-xylitol,1-O-dodecanoyl demonstrated superior docking scores (-8.17 kcal/mol) compared to Levofloxacin, while dodecanoic acid pentafluorophenyl ester exhibited a more favorable binding energy (-40.32 kcal/mol) than Ceftobiprole. ADMET profiling indicated good oral bioavailability, high gastrointestinal absorption, and minimal inhibition of major CYP450 isoenzymes for most compounds. These findings suggest that C. esculentus phytochemicals exhibit notable antibacterial activity and favorable pharmacokinetic properties, highlighting their potential as candidates for novel therapeutics against MDR pathogens. Further investigation, including compound isolation and in vivo studies, is warranted to advance their development.

 Keywords: Cyperus esculentus; Multi-Drug Resistance; Escherichia coli; Staphylococcus aureus Bacteria; Phytochemicals; GC-MS Analysis; Molecular Docking; DNA Gyrase B; Penicillin-Binding Protein 2a

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