Ultrasonic extraction of proanthocyanidins from Litchi chinensis Sonn.

[Object] To optimize the extraction process of proanthocyanidins from Litchi chinensis Sonn.with ultrasonic extraction method.[Method] Litchi chinensis Sonn.as tested material,effects of extractant,volumetric fraction,pH,solid-liquid ratio,ultrasonic power,extracting duration,extraction times and the partical size of Litchi chinensis Sonn.on the yield rate of proanthocyanidins were investigated in this study,and the optimum extraction process of proanthocyanidins was obtained through orthogonal test.[Result] The optimum extraction process of proanthocyanidins was as follows:100 mesh of Litchi chinensis Sonn.powder,solid-liquid ratio of 1:8,ethanol fraction of 70%,pH of 5.0,ultrasonic powder of 600 W,extraction duration of 30 min for one time,and the influence factors were in the order as:extraction durationpartical sizesolid-liquid ratioultrasonic power.[Conclusions] The optimum extraction process of proanthocyanidins from Litchi chinensis Sonn.was obtained in this study,and the yield rate was 13.11%,which would provide reference for the effective utilization of proanthocyanidins and food colors from Litchi chinensis Sonn..