EFFECT OF EXTRACTION CONDITIONS ON TOTAL POLYPHENOL CONTENTS AND ANTIOXIDANT ACTIVITY OF PASSION FRUIT (Passiflora edulis) PEELS

 Passion fruit peel has been extracted by two methods, traditional extraction, and ultrasonic-assisted extraction to obtain the highest polyphenol content and to assess their antioxidant activity. For the traditional extraction method, the highest polyphenol content obtained under conditions of using methanol solvent with the ratio of material/solvent was 1/20 (g/mL) for 60 minutes at a temperature of 60oC. Under these conditions, the polyphenol content was 6.19 mg GAE/g DM (dry matter), the ability to resist oxidation by DPPH (IC50), FRAP, ABTS+ methods were 446 µg/ml, 3.32 mg Fe2+/g DM, 12.93 mg TE/g DM, respectively. With theultrasound-assisted extraction method, the highest polyphenol content was obtained under the use of methanol for solvent, with a power capacity of 45%, a run time of 12 minutes, and a material/solvent ratio of 1/40 (g/mL). Under these conditions, the polyphenol content was 7.35 mg GAE/g DM, the ability to antioxidant determined by DPPH (IC50), FRAP, and ABTS+ methods was 344 µg/mL, 3.89 mg Fe2+/g DM, 14.67 mg TE/g DM, respectively.