Separation And Purification Of Zingiberene From Ginger Essential Oil

Zingiberene is one of biologic active components in ginger essential oil. In this article, zingiberene was separated and purified by silica gel column chromatography from Ginger essential oil extracted by supercritical CO2. The separation conditions and analysis methods of zingiberene were studiedFirstly, the analysis and detection methods of zingiberene were researched. As zingiberene standard material is hardly gotten, the detection method without reference material should be established. The process and main conclusion were shown as bellow. The zingiberene and other olefins UV absorption peakes were determined by comparative analysis of UV, GC-MS and HPLC analysis results. The characteristic absorption peak of zingiberene was at 263nm. The program of qualitative and quantitative analysis of zingiberene was proposed by UV, GC-MS and HPLC. Firstly, qualitative and preliminary quantitative results of zingiberene can be shown by UV analysis at 232nm and 263nm for all separation samples. Secondly, accurate quantification of zingiberene was got by GC-MS analysis for characteristic samples. Finally, HPLC was adopted to be as aided analysis.Secondly, separation of zingiberene from ginger essential oil by silica gel column chromatography was studied. Because of the nature of olefins and phenolics compounds in ginger essential oil vary greatly, the two were separated first. The olefins and phenolics could be separated by silica gel column chromatography at once when the eluant ratio between ether and hexane was 7:3. But olefins gotten was still a mixture. Fine separation of olefins was needed. The conditions of composition and rate of eluant, amount of stationary phase and stationary phase activation conditions have affection for separation result. The determined optimum separation conditions as follows:ether volume fraction was 5% of eluant, eluant flow rate was 2.0ml/min, m (ginger essential oil):m (silica)= 1:50, silicone activation time was lOmin. Under these conditions, three kinds of olefins could be got. The main components of the peak samples of three kinds of olefins could be gained by GC-MS analysis. The peak area percentages of P-phellandrene, zingiberene and a-curcumene were 70.37%,60.41% and 34.17%, respectively. And the recovery of zingiberene was 70.68%. At the same time, silicone recycling method was researched. But the separation effect and economy of silicone recovery should be improved.Finally, zingiberene sample that obtained under the above optimum conditions was purified by silica gel column chromatography once again. The determined purification conditions as follows:ether volume fraction was 3% of eluant, m(ginger essential oil):m(silica)=1:60, eluant flow rate was 2.0ml/min, sample volume was 2.0ml/segment. According to GC-MS analysis, the peak sample of purified zingiberene mainly contained zingiberene andβ-Sesquiphellandrene. The relative content of zingiberene was increased from 60.41% to 70.93%. The HPLC was also chosen to analyze the peak sample of purified zingiberene. The high performance liquid chromatogram had only one peak and the purity of zingiberene could be 94%.