Inhibitory and anti-adherent effects of L. leaf extract against in co-infection with and : A sustainable one-health approach.

Background And Aim: Keratitis is a serious ocular infection often caused by pathogenic microorganisms such as spp. Among other harmful microbes, keratitis presents a particular challenge due to its resistance to conventional antimicrobial agents. Linn., commonly known as betel leaf, has been traditionally used for its medicinal properties. This study aimed to assess the potential of the leaf ethanol extract of Linn. in the treatment of in monoculture and co-culture with two prevalent pathogenic bacteria, and , associated with keratitis.

Materials And Methods: Minimum inhibitory concentrations (MICs) of , , and extracts in monoculture and coinfected conditions were examined. In addition, this study explored the potential of the extract in preventing adherence in both monoculture and co-culture environments. Scanning electron microscopy (SEM) analysis confirmed the impact of the extract on cell membranes, including acanthopodia. Furthermore, a time-kill kinetic assay was used to validate the amoebicidal activity of the extract against and the tested bacteria.

Results: MICs for trophozoites, cysts, , and in the monoculture were 0.25, 0.25, 0.51, and 0.128 mg/mL, respectively, whereas the MICs for coinfected with bacteria were higher than those in the monoculture. This extract inhibited the growth of trophozoites and cysts for up to 72 h. Moreover, extract effectively prevented the adherence of to contact lenses under monoculture conditions. SEM analysis confirmed that extract affects the cell membrane of , including Acanthopodia. In addition, the time-kill kinetic assay confirmed that the extract contained amoebicidal activity against , including the tested bacteria. Notably, was more susceptible than and to extract treatment. Unexpectedly, our study revealed that negatively affected in the co-culture after 3 days of incubation, whereas facilitated the growth of in the presence of the extract.

Conclusion: This study provides compelling evidence of the anti-adhesive and anti- properties of leaf extract against under monoculture and co-culture conditions. The observed impact on cell membranes, coupled with the time-kill kinetic assay results, underscores the potential of leaf extract as a promising agent for combating -related infections in humans and animals.