Comparative Evaluation of the Antibiofilm Activity of Four Terminalia Species Against A Multi-Drug Resistant Uropathogenic Escherichia coli Strain

The global rise of Multi-Drug Resistant (MDR) bacteria, particularly uropathogenic Escherichia coli (UPEC), has rendered conventional antibiotics increasingly ineffective. Biofilm formation is a key virulence factor contributing to this resistance, necessitating the discovery of novel antibiofilm agents. Medicinal plants from the genus Terminalia are traditionally used to treat infections and possess a wide array of phytochemicals. This study evaluated the antibiofilm activity of hydroethanolic extracts from four Terminalia species: T. superba, T. ivorensis, T. mantaly, and T. catappa, against a clinical MDR E. coli strain (1623C-18/ID 102718) isolated from human urine. The crystal violet microtiter plate assay was employed to quantify biofilm inhibition. The Minimum Biofilm Inhibitory Concentration (MBIC) was determined for each extract. The results demonstrated significant variation in antibiofilm potency among the species. Terminalia catappa exhibited the strongest activity with an MBIC of 31.25 µg/mL, followed by T. mantaly (35.15 µg/mL) and T. ivorensis (46.85 µg/mL). Terminalia superba showed moderate activity with an MBIC of 85.93 µg/mL. The high efficacy of T. catappa and T. mantaly suggests their potential as sources of lead compounds for combating biofilm-associated MDR E. coli infections. These findings support the ethnomedicinal use of these plants and warrant further phytochemical isolation and mechanistic studies.