In Vitro Assessment of Aqueous, Acetone and Ethanolic Extracts of Garlic and Turmeric as Plant-based Antimicrobial Agents

Abstract

This study assessed the in vitro, antimicrobial activity of aqueous, acetone, and ethanol extracts of Allium sativum and Curcuma longa against selected bacterial pathogens in order to determine their potential as plant-based antimicrobial agents. The methodology involved preparing different concentrations of extracts using water and ethanol solvents. The antibacterial activity was tested against Escherichia coli and Staphylococcus aureus using the disc diffusion method, with zone diameters measured to determine susceptibility, while minimum inhibitory and bactericidal concentrations were determined using tube dilution and streak plating respectively. The results revealed that garlic extracts exhibited significant antimicrobial effects against all tested bacteria, including Escherichia coli and Staphylococcus aureus. Ethanolic extracts of garlic showed higher efficacy than aqueous extract, with maximum zone inhibition diameters of 18 mm for E. coli and 20 mm for S. aureus at 200 mg/mL for acetone garlic extract. Turmeric extracts demonstrated varying levels of antimicrobial activity, with ethanolic extracts generally more reactive than aqueous extracts. The aqueous turmeric shows no activity at all against S. aureus, and acetone/ethanol turmeric show 18/15 mm at 400 mg/mL. The ethanolic extracts of both garlic and turmeric showed better results compared to aqueous extracts, indicating that organic solvents may be more effective in extracting bioactive compounds responsible for antimicrobial activity. The study highlights the potential of garlic and turmeric as natural antimicrobial agents, with garlic exhibiting superior antibacterial properties. These findings suggest that these spices could be used to develop alternative and complementary medicines. Further research is needed to validate their clinical effectiveness and explore their therapeutic potential.