Optimization of microwave-assisted extraction of polyphenols from apple pomace using response surface methodology and HPLC analysis

J Sep Sci. 2010 Dec;33(23-24):3751-8. doi: 10.1002/jssc.201000430.

Abstract

A simple and efficient microwave-assisted extraction of polyphenols from industrial apple pomace was developed and optimized by the maximization of the yield using response surface methodology. A Box-Behnken design was used to monitor the effect of microwave power, extraction time, ethanol concentration and ratio of solvent to raw material (g/mL) on the polyphenols yield. The results showed that the optimal conditions were as follows: microwave power 650.4 W, extraction time 53.7 s, ethanol concentration 62.1% and ratio of solvent to raw material 22.9:1. Validation tests indicated that the actual yield of polyphenols was 62.68±0.35 mg gallic acid equivalents per 100 g dry apple pomace with RSD=0.86% (n=5) under the optimal conditions, which was in good agreement with the predicted yield and higher than those of reflux and ultrasonic-assisted extraction methods. HPLC analysis indicated that the major polyphenols of apple pomace consisted of chlorogenic acid, caffeic acid, syrigin, procyanidin B2, (-)-epicatechin, cinnamic acid, coumaric acid, phlorizin and quercetin, of which procyanidin B2 had the highest content of 219.4 mg/kg.

Publication types

  • Research Support, Non-U.S. Gov't
  • Validation Study

MeSH terms

  • Chromatography, High Pressure Liquid / methods*
  • Flavonoids / isolation & purification*
  • Malus / chemistry*
  • Microwaves*
  • Phenols / isolation & purification*
  • Polyphenols
  • Reference Standards

Substances

  • Flavonoids
  • Phenols
  • Polyphenols