“Antioxidan Activity from Methanol Extract of Kratom Leaves (Mitragyna speciosa) Maseration Result Using The DPPH Method: Aktivitas Antioksidan Ekstrak Metanol Daun Kratom (Mitragyna speciosa) Hasil Maserasi Menggunakan Metode DPPH” (2023) Journal Pharmasci (Journal of Pharmacy and Science), 8(2), pp. 137–142. doi:10.53342/pharmasci.v8i2.357.