BACTERIOSTATIC ACTIVITY OF Apium graveolens ETHANOLIC EXTRACT AGAINST Staphylococcus aureus AND Escherichia coli

Abstract

Bacterial resistance to synthetic antibiotics has intensified the need for natural antimicrobial alternatives. This study evaluated the antibacterial activity of 96% ethanolic extract of celery stalk (Apium graveolens var. dulce) against Staphylococcus aureus and Escherichia coli using the broth dilution method. The extract was prepared by stepwise maceration in 96% ethanol at a 1:10 crude-to-solvent ratio (6 h with agitation, 18 h standing, followed by re-maceration 3×24 h). Concentrations tested were 3.125%, 6.25%, 12.50%, 25%, and 50%, with Ciprofloxacin (6.5 µg/µL) as positive control and 96% ethanol as negative control. Growth inhibition of S. aureus was detected at 50% (ΔAOD = −0.35), while inhibition of E. coli was observed at 25% (ΔAOD = −0.24) and 50% (ΔAOD = −0.093). Minimum bactericidal concentration testing confirmed bacteriostatic activity across all concentrations. These findings indicate that 96% ethanolic extract of celery stalk possesses concentration-dependent bacteriostatic potential against both bacterial species.