Extraction And Composition Analysis Of Three Kinds Of Cloves Essential Oil, And Their Bacteriostatic Effect Assay

Clove is an Oleaceae and Syringa plant, it has a long history of cultivation in China. Clove is widespread and multitudinous in our country. It is not only an ornamental plant, but also a medicinal plant. In this experiment, I used ultrasound-assisted extraction mothed to extract the volatile oil from flower bud of Syringa oblate, Syringa oblate var affinis Lingelsh and Syringa villosa. Then according to orthogonal experiment I find out the optimum extraction process. At last I indentified the composition of three kinds of volatile oil by GC-MS and measured their bacteria inhibition diameter. The results are as follows:(1)Using the extraction amount of clove essential oil as an index, the influence degree is the soaking time> the ultrasonic time> the ultrasonic frequency>the material liquid ratio. The best extraction process of the flower bud is ultrasonic frequency 60KHz, ultrasonic time 45min (2 times), material liquid ratio 1:20 and soaking time 32h.(2)The flower bud volatile oil of Syringa oblate contains 48 kinds of volatile components, among them ester compounds accounted for 37.92% and alkenes compounds accounted for 20.87%. Other components included these including a small amount of alcohol, olefine and ketone compounds; The flower bud volatile oil of Syringa oblate var affinis Lingelsh contains 65 kinds of volatile components, among them ester compounds accounted for 37.12% and alkanes compounds accounted for 14.75%. Also a small amount of phenol, alcohol and ketone compounds are detected; The flower bud volatile oil of Syringa villosa contains 56 kinds of volatile components, among them acid compounds accounted for 28.4% and ester and alkanes compounds accounted for 21.94% and 13.68% respectively. And a small amount of ketone compounds was also found.(3)The inhibition diameter assay of the volatile oil to Escherichia coli, Bacillus subtilis, Staphylococcus aureus, Agrobacterium and Saccharomyces cerevisiae showed that the lilac flower bud volatile oil has the antibacterial effect on E.coli. The average inhibition diameter is 16mm. Red lilac flower bud has inhibitory effect on B.subtilis and S.cerevisiae, the average inhibition zone diameter were 17mm and 0.9mm respectively.