IN VITRO EVALUATION OF THE ANTIBACTERIAL EFFICACY OF ACORUS CALAMUS LINN. ROOT EXTRACT AGAINST SELECTED GRAM-POSITIVE AND GRAM-NEGATIVE BACTERIAL PATHOGENS

The in vitro antibacterial efficacy of the aqueous root extract of Acorus calamus Linn. was evaluated against four bacterial strains, namely Escherichia coli, Proteus vulgaris, Bacillus subtilis, and Staphylococcus aureus, at concentrations ranging from 10% to 100%. The extract exhibited the highest antibacterial activity against S. aureus, producing an inhibition zone of 34.0 mm at 100% concentration, followed by P. vulgaris (32.0 mm at 100%), B. subtilis (28.0 mm at 100%), and E. coli which showed the lowest inhibition (23.0 mm at 60%). When compared with standard antibiotics, tetracycline (25 mg/mL) exhibited inhibition zones of 30.0 mm for E. coli, 18.0 mm for P. vulgaris, 26.0 mm for S. aureus, and 23.0 mm for B. subtilis. Similarly, chloramphenicol (25 mg/mL) showed maximum inhibition against P. vulgaris (31.0 mm), followed by E. coli (30.0 mm), while both S. aureus and B. subtilis recorded inhibition zones of 28.0 mm each. These results indicate that the aqueous root extract of Acorus calamus possesses significant antibacterial potential, particularly against Staphylococcus aureus and Proteus vulgaris, suggesting its possible use as a natural antimicrobial agent.