This research was conducted from February to May 2024 at Bandar Bakau, Pangkalan Sesai Village, West Dumai. Samples taken in the form of mangrove leaves, then analyzed at the Marine Microbiology Laboratory, Department of Marine Science, Faculty of Fisheries and Marine Sciences, Riau University. The purpose of this study was to determine the potential of R. apiculata mangrove leaf extract to be …