Aktivitas Antioksidan Seduhan Daun Ketapang (Terminalia catappa L.) dengan Metode DPPH
Ketapang is a plant that is often found in Indonesia and is widely used as a medicinal plant. Ketapang leaves contain phenolic compounds which are efficacious as antioxidants. The purpose of this study was to determine the antioxidant activity of steeping ketapang leaves in the form of dried simplicia. Antioxidant activity was measured using the DPPH method (1,1-diphenyl-2-picryl hydrazyl). The sample tested for dried ketapang leaf simplicia was prepared using sieve number 8 and then brewed using distilled water with an initial temperature of 95oC. Brewing is done for 30 minutes and the steeping temperature will drop. Samples of steeping dried ketapang leaves were made with concentration series of 625 ppm, 1250 ppm, 2500 ppm, 5000 ppm and 10,000 ppm. The reference solution used was quercetin with concentration series of 1 ppm, 5 ppm, 10 ppm, 15 ppm, 20 ppm and 25 ppm. Antioxidant activity testing was carried out using the DPPH method. Antioxidant activity was calculated in the value of % inhibition and IC50 (50% Inhibitory Concentration). The significance of the difference between the sample and the controls was analyzed using SPSS 23. The results showed that steeping ketapang leaves and quercetin had IC50 values of 10,020.79 ± 45.69 and 18.98 ± 0.41, respectively. The DPPH free radical inhibition value indicated that the steeping of ketapang leaves had weaker antioxidant activity than quercetin.