Optimization of Extraction, Compositional Analysis and Biological Activities of Fructus Ligustri Lucidi Essential Oil

Fructus Ligustri Lucidi (FLL) refers to the dried mature fruit of Ligustrum lucidum Ait., a species from the Oleaceae family, widely distributed across East Asia and India. This study aimed to optimize the extraction process for Fructus Ligustri Lucidi essential oil (FLLO) to develop an efficient and practical extraction method. Additionally, the chemical composition of FLLO was analyzed, and its antioxidant, antimicrobial, and cytotoxic activities were evaluated. FLLO was extracted using supercritical CO2 extraction, and response surface methodology was applied to optimize the extraction parameters: pressure of 16 MPa, temperature of 40 degrees C, and extraction time of 40 min. The main components of the essential oil were identified through GC-MS analysis. Antioxidant activity was assessed using DPPH and ABTS assays, demonstrating that FLLO exhibited strong antioxidant properties, with a DPPH radical scavenging rate exceeding 80%. In antimicrobial tests, FLLO exhibited significant inhibitory effects on both Gram-positive and Gram-negative bacteria at concentrations greater than 25 mg/mL. Additionally, cytotoxicity assays revealed that FLLO enhanced the proliferation of LO2 cells. In conclusion, FLLO, extracted using supercritical CO2, demonstrates excellent antioxidant and antimicrobial properties, as well as favorable cell safety, supporting its potential for further development and application of Ligustrum lucidum.