Antibacterial and antibiotic-potentiation activities of the hydro-ethanolic extract and protoberberine alkaloids from the stem bark of Enantia chlorantha against multidrug-resistant bacteria expressing active efflux pumps

ECB and compounds 1–5 showed antibacterial activities against all Gram-negative and Gram-positive bacteria tested. The efflux pump inhibitor (EPI), phenylalanine-arginine-β naphthylamide (PAβN) significantly improved the activity of compounds 1–6. Compounds 1–3 significantly potentiated the antibacterial activity of antibiotics such NOR, CIP, and DOX against the tested MDR bacteria. ECB and compound 1 altered the H + -ATPase pump and inhibited cellular ATP production.Image 1