Loureirin A is a narrow-spectrum antimicrobial agent against .

Currently, eradication by antibiotic therapy faces various challenges, including antibiotic resistance, side effects on intestinal commensal bacteria, and patient compliance. In this study, loureirin A (LrA), a traditional Chinese medicine monomer extracted from Sanguis Draconis flavones, was found to possess specific antibacterial activity against without the bacteria displaying a tendency to develop resistance . LrA demonstrated a synergistic or additive effect when combined with omeprazole (a proton pump inhibitor) against . The combination of LrA and omeprazole showed promising anti-. potential, exhibiting notable efficacy comparable to standard triple therapy in mouse models infected with both drug-sensitive and drug-resistant strains. Moreover, the narrow-spectrum antibacterial profile of LrA is reflected in its minimal effect on the diversity and composition of the mouse gut microbiota. The underlying mechanism of action of LrA against involves the generation of bactericidal levels of reactive oxygen species, resulting in apoptosis-like cell death. These findings indicate that LrA is a promising lead compound targeting without harming the commensal bacteria.