Abstract:Using the sour papaya as raw material，the total flavonoids in the fruit peel，pulp and seeds were extracted by ultrasonic ethanol assisted method.Orthogonal test was conducted on the parts with the highest yield of total flavonoids.The single factor test results showed that the total flavonoid yield increased with the increase of ethanol volume fraction in the fruit peel，pulp and seeds，but when the volume fraction of ethanol was more than 60%，the total flavonoid yield decreased.The yield of total flavonoids in the fruit peel，pulp and seeds of sour papaya showed an increasing trend with the increase of ultrasonic extraction time，but the yield of total flavonoids decreased after the ultrasonic time exceeded 30 min.The total flavonoid yield reached the maximum when the solid liquid ratio reached 1 ∶25（g/mL）.The yield of total flavonoids increased first and then decreased with the change of ultrasonic power.When the ultrasonic power reached 198W，the total flavonoid yield was the highest.The results showed that the yield of total flavonoids in sour papaya fruit peel was significantly higher than that of pulp and seed，so the sour papaya fruit peel was selected for orthogonal test.The results of orthogonal test showed that ultrasonic time was 25 min，ultrasonic power was 231 W and the solid liquid ratio was 1∶25（g/mL），the volume fraction of ethanol was 60%，which was the optimal extraction condition for the extraction of total flavonoids from sour papaya fruit peel.The total flavonoid yield under this condition was 7.31%.