Abstract:

Ultrasonic treatment was applied to the ethanol extraction of flavonoids from navel orange peel. The effects of four crucial variables such as ultrasonic power, ethanol concentration, material/liquid ratio and ultrasonic treatment time on the yield of flavonoids were investigated by single-factor method. An orthogonal array design leading to a set of 9 combinations of these variables was performed to obtain the highest yield of flavonoids. Under the optimized conditions as follows: ultrasonic power 125 W, 60% alcohol as the extraction solvent, material/liquid ratio 1: 35, and extraction time 60 min, a yield of flavonoids of 49.3 mg/g was achieved.

Key words: ultrasonic, flavonoids, extraction