An unhealthy lifestyle will usually cause free radical compounds that are reactive against cells and tissues of the body. Therefore free radical reactions in the body can be muted with the use of antioxidants that can help protect the body from free radical attack and resist its negative impact. The synthetic antioxidants such as BHA and BHT can cause damage to the liver and carcinogenic. Some scientific studies around the world identify compounds that have potential pharmacological activity as an antioxidant have low side effects. This study aims to determine the potential of Seluang Belum Roots (Luvunga sarmentosa (Blume) Kurz.) have activity as an antioxidant using ABTS method. Seluang belum root’s (Luvunga sarmentosa (Blume) Kurz.) is a traditional Kalimantan plant that contains chemical compounds that have potential as antioxidants that can inhibit free radicals. It extracted using the ultrasonic-assisted extraction (UAE) method with a 150 g sample/ 600 mL solvent ratio (1:4g/mL) and extraction time of 15 minutes. The test group divided into five concentrations and vitamin C as a positive control. Each level of ABTS added as much as 1 ml and then measured on ultraviolet-visible (UV-Vis) spectrophotometer with a wavelength of 750 nm. The IC50 value of Seluang Belum by 42.54 ppm. The Seluang Belum Root’s as a traditional plant from Kalimantan can be one of the alternative therapy made from the natural potential to have antioxidant activity which is very strong.

Keywords: Antioxidant, Luvunga sarmentosa (Blume) Kurz., Ultrasonic Assisted Extraction, ABTS