Optimization of conditions for extraction of total polyphenols from dried tumeric (Curcuma longa L.) leaves using Response Surface Methodology

Abstract

Turmeric (Curcuma longa Linn) is a member of the Zingiberaceae family which is cultivated in tropical such as Vietnam and subtropical regions on over the world. Response surface method was used to optimize polyphenol compounds from dried tumeric leaves in different extraction conditions. Three main factors effect on total polyphenol content from dried tumeric leaves that include: extraction temperature (50, 60, and 70 °C), duration (40, 50, and 60 minutes), and solvent concentration (40, 50, and 60 %). The results of research showed that the optimal extraction condition of polyphenol from tumeric leaves was temperature at 68.3 °C for 59.9 minutes and 40 % ethanol that would give the highest polyphenols content 64.2 mg GAE/g DW. The results of this research indicated that the potential of using tumeric leaves as sources of natural antioxidant compounds.