Abstract: In order to achieve efficient utilization of bitter apricot kernel meal (Prunus armeniaca), the effect of blanching on the amygdalin content of bitter apricot kernels with skin, and the optimization of the ultrasonic-assisted extraction of amygdalin from bitter apricot kernel meal left after pressing out oil using response surface methodology was investigated as well as the preparation of highly pure amygdalin from crude extract. The results showed that significant enzyme inactivation and good retention of amygdalin were simultaneously achieved by blanching in a 5-fold volume of boiling water for 10 min, and the relative content of amydalin was (4.72 ± 0.14)% after blanching. The maximum extraction rate of amygdalin of 8.03% was obtained when the extraction was carried out twice using 73% ethanol as extraction solvent at a solvent-to-solid ratio of 8:1 with 20 min ultrasonication. The crude extract obtained was purified by high performance centrifugal partition chromatography (HPCPC), and it turned out that amygdalin with the highest purity of 96.14% was obtained by using the upper organic phase of n-butanol/ethyl acetate/methanol/water (2.5:0.625:0.5:4, V/V) as the stationary phase and the lower aqueous phase of the mixed system as the mobile phase at a centrifugal speed of 900 r/min and at a flow rate of 2.0 mL/min.

Key words: bitter apricot kernel meal, ultrasonic-assised extraction, amygdalin, high performance centrifugal partition chromatography (HPCPC)