Ultrasound-assisted extraction of polysaccharide from Nephelium lappaceum L. fruit peel

In this study, ultrasound-assisted extraction technology was employed to investigate and optimize the crude polysaccharide extraction from Nephelium lappaceum L. fruit peel using three levels, four factors (LS ratio, ultrasonic power, extraction temperature and extraction time) Box-Behnken response surface design. The results showed that highest polysaccharide yield of 8.31% was obtained with an LS ratio of 32:1 ml:g, ultrasonic power of 110 W, extraction temperature of 53 °C and extraction time of 41 min. The experimental yield of polysaccharide (8.29 ± 0.03%) at optimal condition was well agreed with the predicted value. Fourier transform infrared spectroscopy (FTIR) was used for the identification of functional groups present in the extracted polysaccharide. The results suggest that ultrasound-assisted extraction could be a good alternative for the extraction of polysaccharide from N. lappaceum L. fruit peel at industrial level.