Green extraction of bioactive flavonoids in Scutellariae Radix using deep eutectic solvents-based ultrasound-assisted...

An efficient and sustainable deep eutectic solvents-based ultrasound-assisted matrix solid phase dispersion (DES-UAMSPD) method was proposed for extracting the bioactive flavonoids in Scutellariae Radix (SR), with molecular sieve (ZSM-5) as dispersant and betaine-levulinic acid (Bet-Lea (1:2, 50 % water content)) as the effective extractant. The interaction mechanism of DES formation and extraction process was comprehensively elucidated by computer simulation techniques such as electrostatic potential (ESP) distributions, independent gradient model based on hirshfeld partition (IGMH) and frontier molecular orbitals theory. The response surface methodology experiments were conducted to optimize the extraction conditions. Under optimal extraction conditions, the total content of five analytes (baicalin, oroxyloside, wogonoside, baicalein and wogonin) reached 182.66 mg g^-1, which was 1.50-2.19 folds higher than conventional extraction solvents. The greenness and environmental friendliness of the proposed method were evaluated through Green Analytical Procedure Index and Analytical Eco-Scale. Additionally, this quantitative method exhibited reliable linearity for the analytes (r² > 0.9997) and excellent recovery (95.4 %-102 %, RSD < 2.72 %). The limits of detection ranged from 0.02 to 0.04 μg mL^-1. Overall, these results highlighted the excellent extraction and quantification capability of the proposed approach, which offered an environmentally friendly strategy for effective extraction of bioactive compounds from natural products.