Total phenolic content and potential of black betel leaf (Piper betle L.var nigra) extract as an antioxidant and anti-gout

Research to find antioxidants and anti-gout has been done using black betel leaf. The sample was extracted at room temperature for 30 minutes using the Ultrasound-Assisted Extraction (UAE) method, and a yield of 8.47% was obtained. Phytochemical screening was carried out on the ethanol extract of black betel leaves and showed the presence of secondary metabolite compounds consisting of alkaloids, phenolics, saponins, tannins, and steroid glycosides, with a total phenolic content of 758,534±0.003mg GAE per gram of sample. Antioxidant activity analysis was carried out using the 1,1-diphenyl-2-picrylhydrazyl (DPPH) and Ferric Reducing Antioxidant Power (FRAP) methods, which showed IC50 and EC50 values of 115.562±0.14mg/L and 119.273±0.385 mg/L, respectively. The antioxidant activity of black betel leaf extract is in the medium category (100-150 mg/L). The anti-gout activity test was carried out using allopurinol as a control, which showed the ability of black betel leaf extract to reduce uric acid up to 14.48±0.01%. The ability of black betel leaf extract as an anti-uric acid is five times better than allopurinol, which is commonly used as a gout drug. The research results obtained opened up the opportunity to find a natural medicine for gout.