Polyphenols are widely distributed in the plant kingdom and are important components of common foods, including tea, red wine, fruits, beverages and various medicinal plants. Among them, ellagic acid (EA), dimeric derivative of gallic acida[1]. Extraction and determination of ellagic acid in walnut(Juglans regia L.) leaves using hallow fiber liquid phase microextraction(HF-LPME) and high performance liquid chromatography(HPLC). Effective factors on HF-LPME including nature of organic extraction solvant, pH of donor and acceptor phases, stirring speed of sample solution, extraction time and salt addition to the sample solution were investigated and optimized. Determination of ellagic acid by HPLC using a mobile phase consisting of methanol:phosphoric acid:THF(47:52:1,v/v%) and uv detector at 254 nm.Under the optimized conditions(1-octanol as organic extraction solvant, pH of donor phase =2.0, pH of acceptor phase=8.66, stirring speed=800 rpm, extraction time=80 min).
