Extraction Optimization, Composition Analysis of Volatile Oil from Litsea lancilimba Merr. and Its Antioxidant Activity

In order to study the optimal extraction process, composition and antioxidant activity of the Litsea lancilimba Merr. volatile oil, using the extraction rate of the Litsea lancilimba Merr. volatile oil as index, based on the single factor test, the response surface method was used to investigate the extraction process; GC-MS was used to analysis the composition of volatile oil; DPPH· scavenging test was used to evaluate the in vitro antioxidant activity of Litsea lancilimba Merr. volatile oil. The results showed that the best extraction process was soak time 5 h, 5 times the material-liquid ratio, and extraction time 8 h. Under the above conditions, the extraction rate was 10.67%. 74 components were identified from the Litsea lancilimba Merr. volatile oil by GC-MS, accounting for 93.175% of the total volatile oil. Among them, the relative contents higher than 3% were 1, 8-cineole (21.854%), n-decanoic acid (12.893%), β-pinene (4.873%), p-cymene (4.579%), α-pinene (4.452%), lauric acid (3.734%), α-terpinenol (3.188%). The total antioxidant activity of Litsea lancilimba Merr. volatile oil gradually increased with the increase of the concentration. When the concentration was in the range of 1.0~6.0 mg/mL, the highest clearance rate was 92.94%. The optimized process was suitable for the extraction of Litsea lancilimba Merr. volatile oil. There were many components in the Litsea lancilimba Merr. volatile oil, among which terpenoids, hydrocarbons and acids were the main components. The antioxidant results indicate that it has a certain in vitro antioxidant capacity.