Ultrasonic-assisted green extraction of peach gum polysaccharide for blue-emitting carbon dots synthesis

Raw peach gum is hard crystalline-like solid with very poor solubility, significantly restricting its application in various fields. This study optimized the parameters for ultrasonic-assisted peach gum polysaccharides (UPGP) extraction. The results showed that the maximum extraction rate was up to 80.1% under the optimized conditions of 5 h extraction time, 90 mL/g water to raw peach gum ratio and 532 W ultrasonic intensity at 95 °C. The acquired UPGP mainly consisted of Ara, Gal and Man with a molecular weight of 8.18 × 10 6 g/mol. Moreover, the UPGP has been used as a green precursor for carbon dots (CDs) preparation through a simple one-step hydrothermal reaction. The synthesized CDs had a mean particle diameter of 7.66 nm and showed excellent fluorescence intensity and stability. Thus, this study improved the utilization of raw peach gum and further broadened the UPGP application. • UAGE was firstly applied to extract peach gum polysaccharide. • The degradation rate of UPGP was up to 34.03% compared to PGP. • UPGP-based CDs were firstly synthesized through a simple hydrothermal reaction. • UPGP-based CDs showed excellent fluorescence intensity and stability.