Extraction of <i>Phyllanthus emblica L.</i> flavonoids by ultrasound-assisted enzymatic hydrolysis method and antioxidant stress effects

This research used ultrasound-assisted enzymatic hydrolysis (UEAE) to extract flavonoids from <i>Phyllanthus emblica L.</i>, and combined Plackett-Burman experiments (PB) and response surface experiments (RSM) to optimise the extraction process of UEAE. Under optimal conditions, the <i>Phyllanthus emblica L.</i> flavonoids (PEF) yield reached 10.04 ± 0.40%, which was 65% higher than that obtained by the traditional thermal reflux method. Purification with AB-8 macroporous resin achieved a final PEF purity of 70.29%. Passed the free radical scavenging experiment, and intracellular levels of glutathione (7.82 μmol/gprot), total superoxide dismutase (74.96 U/mgprot), catalase (14.21 U/mgprot), malondialdehyde (18.87 nmol/mgprot), and reactive oxygen species (ROS) experiments, PEF effectively mitigated the oxidative stress damage in H₂O₂-induced RAW264.7 cells. These experimental results indicated that purified PEF exhibited excellent antioxidant stress activity. This study provides data references for the development and application of <i>Phyllanthus emblica L.</i> in sectors such as food and pharmaceuticals.