Antioxidant activities of papaya leaf extracts with different extraction solvents

The bioactive compounds of payapa leaf were extracted by water, 70% methanol and 70% ethanol. The extraction efficiency, contents of total phenol and flavonoid were determined. The scavenging abilities of free radicals, metal chelating capacity ( MCC) and ferric reducing antioxidant power ( FRAP) of the three extracts were also investigated. Results showed that the order of extraction efficiency and total phenol content was as follows: water > 70% methanol > 70% ethanol, while the order of total flavonoid was the opposite.The three extracts obtained by three solvents all possessed excellent DPPH·, ABTS⁺·and·OH radicals scavenging abilities, MCC and FRAP.70% methanol was chosen as the most appropriate solvent for the extraction of papaya leaf.The research here not only provided experimental basis for the usage of papaya leaf in the synthesis of natural antioxidants, but also improved the overall value of papaya.