Highly efficient extraction of mulberry anthocyanins in deep eutectic solvents: Insights of degradation kinetics and stability evaluation

In this work, an efficient strategy for extracting mulberry anthocyanins using deep eutectic solvents (DESs) was developed. Results show that both the hydrogen bond acceptors and hydrogen bond donors profoundly influenced the density, water content, and viscosity of the DESs. Six newly prepared DESs exhibited higher extraction amounts of anthocyanins than that of the acidified ethanol. Influence factors on choline chloride (ChCl)-lactic acid (HL) (1:2)-mediated extractability were optimized by response surface methodology (RSM). The optimal condition was acquired at 57.24 °C, for 31.54 min, and 10.76 mL/g, where 6.84 ± 0.21 mg/g of anthocyanins was extracted. Notably, the decreased thermal degradation rate constant, improved half-life time, and prolonged storage time of the anthocyanins in ChCl/HL demonstrated the superiority of DESs in the extraction technique over conventional solvents, which might be attributed to the wide and strong hydrogen bond network formed between the DES component with solute and water molecular.