Comparative effect of the antibacterial activities between the aqueous and alcoholic extracts of Licorice plant versus antibiotics on the Gram positive and negative bacteria

Background: Licorice roots (Glycyrrhiza glabra) are plants that have been used in medicine and pharmacy for centuries as a valuable source of bioactive compounds as anti-inflammatory, antiviral, antibacterial, and anticancer properties. Aim: The present study aimed to investigate the antibacterial potential of licorice extracts at different concentrations and to compare their performance with the conventional antibiotic. Methods: The active ingredient of licorice roots was extracted by passing it in water and methanol, and preparing it for the purpose of the study, where the aqueous and alcoholic (methanolic) extract was prepared in different concentrations as follows: 500 mg/ml and 250 mg/ml as an aqueous solution and 500 mg/ml and 130 mg/ml as an alcoholic solution. On the other hand, pathogenic bacterial isolates (E. coli and Staph. aureus) were collected. Results: The antibacterial activity of both aqueous and alcoholic (methanolic) extracts of licorice plant was evaluated against pathogenic bacterial isolates, Staph. aureus (Gram-positive) and E. coli (Gram-negative). The results confirmed the inhibitory potential of both extracts, as evidenced by the formation of inhibition zones of varying diameters in a dose dependent manner. Conclusion: The aqueous and methanolic extracts of licorice were the most antibacterial activity against both gram positive and negative bacteria. Their effectiveness against these strains suggests that licorice provides a promising alternative therapeutic agent.