Cultivation of Antioxidant-Producing Endophytic Fungus in Rhizophora apiculata Mangrove Plants

West Sumatra is known as one of the largest areas of mangrove forests in Indonesia, dominated by Rhizophora. Therefore, there will be huge opportunities to discover new types or strains of endophytes and antioxidant compounds, which play an important role in protecting cells caused by free radicals, preventing oxidation, and protecting the human body from ROS. This study aims to determine the optimal pH and temperature for growth and antioxidant activity of endophytic fungal isolates of mangrove plants Rhizophora apiculata using descriptive design with DPPH (2,2-diphenyl-1-picrylhydrazyl) method as determination of antioxidant activity and quantitative analysis of IC50 value. The result showed that the optimum pH for antioxidant activity of isolate EUA-111 was 5.0, EUA-112 was 5.5 and EUA-130 was 6.0. In addition, the optimum temperature for all isolates was 31°C. pH and temperature affect the increase in antioxidant production in endophytic fungal isolates of R. apiculata