Antioxidant Activity, Free Radical Scavenging Potential and Chemical Composition of Litsea cubeba Essential Oil

The antioxidant activity and free radical scavenging potential of Litsea cubeba essential oil (LCEO) were evaluated from different points of view and compared with citral, a major component in LCEO, ascorbic acid (Vc) and synthetic antioxidants including butylated hydroxytoluene (BHT) and propyl gallate (PG). The results revealed that LCEO has notable antioxidant activity. The order of hydroxyl radical scavenging activity was LCEO > BHT > citral > PG > Vc. Their half maximal inhibitory concentration (IC50) values of hydroxyl radical scavenging activity were 0.19, 0.28, 0.50, 0.79 and 1.07 mg/mL, respectively, and IC50 values of scavenging superoxide were 0.45, 0.64, 0.67, 1.08 and 0.51 mg/mL, respectively. Furthermore, the peroxidation of linoleic acid was significantly suppressed by the addition of LCEO. The order of activity was BHT >Vc >LCEO >citral >PG. Chemical composition of LCEO was identified by GC and GC-MS, and major components in the oil were limonene (26.25 %), followed by a-citral (25.97 %), beta-citral (21.90 %), and beta-pinene (6.20 %). Citral plays an important role in antioxidant activity and free radical scavenging.