DETERMINATION OF ANTIOXIDANT CAPACITY IN PLUCHEA INDICA LESS LEAVES EXTRACT AND ITS FRACTIONS
<p><strong>Objective: </strong>This study was conducted to determine the DPPH free radical scavenging activity of pluchea extract (PE) and its fraction (ethyl acetate (EAF), n-butanol (BF) and aqueous (AF)) and comparing with the its activity of control antioxidant, such as green tea (GE) and rosemary extracts (RE), α-tocopherol succinate (ATS) and BHT.</p><p><strong>Methods</strong>:<strong> </strong>The antioxidant activity was evaluated by the decrease in absorbance as the result of DPPH˙ color change from purple to yellow at 517 nm by using a stopped-flow spectrometer UV-Vis. AE (antiradical efficiency) was a parameter more exactly used to measure the antioxidant power than EC<sub>50 </sub>(efficient concentration to reduce 50% of DPPH concentration). This parameter was determined by EC<sub>50</sub> and TEC<sub>50</sub> (the time needed to reach the steady state).</p><p><strong>Results: </strong>PE and its fraction had free radical-scavenging activity compared with control antioxidant. Based on EC<sub>50</sub>, the orders of ability to scavenging DPPH radicals was determined as the EAF~ GE>PE ~ ATS ~ RE ~ AF>BHT ~ BF. The results were not exactly because BHT and ATS were potentially as a synthetic antioxidant. Therefore AE parameter was used to determine scavenging activity. The classification order of scavenging activity based on AE was BHT>GE ~ ATS>EAF>RE~ BF~ PE~ AF.</p><p><strong>Conclusion: </strong>The PE and its fractions had DPPH free radical scavenging activity. Based on EC<sub>50</sub> and AE parameters, the EAF showed the strongest DPPH free radical scavenging activity compared with PE and the other fractions.</p>