High-voltage pulse-assisted extraction of flavonoids from kapok using deep eutectic solvent aqueous solutions

In this study, deep eutectic solvents coupled with a pulsed electric field (PEF-DES) were first applied to the extraction of traditional Chinese medicine plants. This study uses the PEF-DES extraction technique to extract TG-KF (Kapok flavonoid solution extracted with DES-TG). PEF-DES is a simple, effective and environmentally-friendly technology and can be used in industrial-scale production. For the optimal extraction conditions of TG-KF, DES-TG was used as a solvent, the DES-TG concentration was 50%, the solid-liquid ratio was 1 : 30, the electric field intensity was 0.55 kV cm^-1, the number of pulses was 100, and the yield of flavonoids was 14.36 ± 0.35%. TG-KF has very good stability and there is no precipitation or discoloration within 6 months. The results of chicken embryo experiments and human patch tests show that 10% TG-KF aqueous solution has no irritation. DPPH experiments show that TG-KF has excellent efficacy as an antioxidant. Overall, TG-KF is expected to become a potential antioxidant raw material.