Natural deep eutectic solvents couple with integrative extraction technique as an effective approach for mulberry anthocyanin extraction

Natural deep eutectic solvents (NADES) have been growing interest as an alternative to the traditional organic solvents. They not only have the merit of high efficiency but also have the possibility to readily applicable to pharmaceutical and food applications. In the present study, NADES with high-speed homogenization and cavitation-burst extraction (HSH-CBE) was performed on fresh mulberry for anthocyanins extraction. The extraction conditions were statistically investigated by Plackett-Burman design (PBD) and Box-Behnken design (BBD). The optimal conditions were obtained as follows: chloride-citric acid-glucose formed a NADES with the mole ratio of 1:1:1, 30% water content, liquid-solid ratio 22 mL/g, homogenization time 60 s, homogenization speed 12,000 rpm, extraction time 30 min, negative pressure -0.08 MPa and extraction two times. The total maximum extraction of anthocyanins reached 6.05 mg/g fresh weight, which was 1.24 folds to those by the traditional organic solvents extraction. Moreover, NADES exhibited higher stability of anthocyanins extraction than traditional organic solvents, which was benefit for the analysis and preservation of anthocyanins. Consequently, this result revealed that the developed method could be taken as a sustainable, green and effective approach for anthocyanins extraction.