Eco-friendly and efficient extraction of polyphenols from Ligustrum robustum by deep eutectic solvent assisted ultrasound
Guifang Qin, Feng Zhang, Mengdie Ren, Xiuwen Chen, Chao Liu, Gang Li, Qiong Gao, Lei Qiao, Yongmei Jiang, Lei Zhu, Yingying Guo, Wang Gang
Abstract
An eco-friendly and efficient extraction method using deep eutectic solvents assisted ultrasound extraction (DESs-UAE) for the polyphenols from Ligustrum robustum was developed. Among the 34 kinds of DESs prepared, tetraethyl ammonium bromide: 1,2,4-butanol (Teab: 1,2,4-But) was proved to be a suitable extraction solvent based on the extraction efficiency. The extraction parameters including temperature, water content, liquid-solid ratio were optimized with response surface methodology (RSM). Under the optimal conditions, the total phenolic content (TPC) and total flavonoid content (TFC) were 101.46 ± 2.96 mg GAE/g DW and 264.17 ± 5.39 mg RE/g DW, respectively. Furthermore, the extraction mechanism of DESs-UAE was investigated by extraction kinetics, molecular dynamic simulation and theory calculations of interaction. In particular, 9 kinds of polyphenols compounds from Ligustrum robustum were firstly identified by UPLC-Q-TOF-MS. Moreover, the recovered polyphenols exhibited significant antioxidant, α-glucosidase inhibition, acetylcholinesterase inhibition and anticancer activity.