P30 GC–MS analysis and pharmacological activity study of the essential oil from Allium cepa

Allium cepa is a medicinal and edible plant, which is used for preventing and treating arteriosclerosis in traditional medicine. To evaluate the free radical scavenging activity, antitumor activity and acetylcholinesterase inhibitory activity of the essential oil from Allium cepa , this study used the volatile oil extractor to obtain the oil from fresh Allium cepa , and then used GC–MS to analyse the fat-soluble components in the essential oil. The results from GC–MS analysis showed that there were 66 fat-soluble components in Allium cepa oil, of which 25 were organosulfur compounds, accounting for about 30.38% of the total content. The results from the antioxidant experiments showed that at 100 μg/ml, the scavenging rate of Allium cepa oil against ABTS radical was 25.51% (rutin, 39.86%), and the scavenging rate of Allium cepa oil against DPPH radical was 21.65% (rutin, 29.57%). The acetylcholinesterase inhibitory activity results indicated that at 100 μg/ml, the acetylcholinesterase inhibitory rate of Allium cepa oil was 41.46% (Huperzine A, 89.95%). The results from the MTT assay demonstrated that at 100 μg/ml, the inhibition rate of Allium cepa oil against U266 cells was −20.48% (taxol, 51.62%), while the inhibition rate of Allium cepa oil against A549 cells was −156.93% (taxol, 67.08%). In conclusion, Allium cepa oil exhibited antioxidant activity and acetylcholinesterase inhibitory activity to some extent, but possessed no antitumor activity in vitro against A549 and U266 tumor cells. Overall, the present study contributed valuable information concerning Allium cepa use in pharmacology and medicine.