Antibacterial activity of 1,8-cineole and α-terpineol bioactive from cardamom against multi-drug-resistant Escherichia coli isolated from urinary tract infections-an in vitro study

Background: Urinary tract infections (UTIs) are some of the most commonly encountered infections in clinical practice that affects 150 million people each year worldwide. The emergence of resistance, adverse effects of antimicrobial agents, and other related issues have prompted the establishment of a research framework to explore alternative methods for managing UTIs. Cardamom exhibits unique botanical characteristics and biochemical compositions, contributing to their diverse culinary and medicinal applications. Techniques like gas chromatography-mass spectrometry analysis have identified 1,8-cineole and a-terpineol as main bioactive components in both black and green cardamom. Present study addresses urgent, unmet analytical and clinical care needs by exploring adoption of alternative therapies, specifically nutraceuticals viz, 1, 8-cineole and α-terpineol, major bioactive from cardamon for controlling and treating UTIs. Methods: Different concentrations of 1,8-cineole, α-terpineol and 1,8-cineole/α-terpineol (1:1) were used to determine the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) against multi-drug resistant (MDR) E. coli isolated from UTIs. Results: The mean MIC and MBC of 1,8-cineole, α-terpineol and 1,8-cineole/α-terpineol (1:1) for MDR E. coli strains were 7.73 µg/ml, 0.32 µg/ml and 0.32 µg/ml respectively. For non MDR E. coli strains the mean MIC and MBC of the 1, 8-cineole, α-terpineol and 1,8-cineole/α-terpineol (1:1) were 2.14 µg/ml, 0.2 µg/ml and the 0.2 µg/ml respectively. Conclusions: 1,8-cineole and α-terpineol exhibited good antimicrobial activity against urinary E. coli isolates tested, including MDR strains.