Study On The Green Transformation Of 6-gingerol And New Analytical Methods For Gingerol Series Compound

Ginger（Zingiber Officinale Rosc）belongs to the Zingiberaceae herb and contains many nutrients and active compounds,among which ginger oleoresin and ginger essential oil are widely studied.Ginger oleoresin contains more active ingredients of gingerols,such as 6-shogaol,6-gingerol,8-gingerol and 10-gingerol,etc.The content of these gingerols is often used as a quality indicator for judging ginger and its later-processed products.Among them,6-gingerol and 6-shogaol are the two most important bioactive components in ginger,which have been used in medicine and cosmetics,health care products and other industries.The main research contents and results of this paper are as follows:1.Using Guizhou turmeric as raw material,five kinds of extracts were obtained by different processes:supercritical CO₂ ginger oil,steam distillation ginger essential oil,ethanol solvent ginger oil,supercritical CO₂ ginger essential oil,supercritical CO₂ginger oleoresin.Through GC-MS and HPLC analysis and comparison,it is found that the chemical compositions of supercritical CO₂ ginger oil and ethanol solvent ginger oil are relatively close,and the chemical compositions of steam distillation ginger essential oil and supercritical CO₂ ginger essential oil are relatively close.By changing the temperature,pressure and other parameters in the supercritical CO₂ extraction process,three kinds of extracts can be obtained,namely supercritical CO₂ ginger essential oil,ginger oil and ginger oleoresin.6-gingerol in ginger oleoresin has the highest content.Therefore,supercritical CO₂ ginger oleoresin is used as the raw material for the synthesis of 6-shogaol through dehydration reaction of 6-gingerol.2.Using supercritical CO₂ ginger oleoresin rich in 6-gingerol as the raw material,the dehydration reaction of 6-gingerol in supercritical CO₂-BMIm HSO₄ system was used to synthesize 6-shogaol.Firstly,the catalytic effects of three acidic ionic liquids,BSO₃HMIm OTf,BSO₃HMIm HSO₄,and BMIm HSO₄ at different temperatures and pressures were compared.BMIm HSO₄ was selected as the catalyst.Anhydrous Na₂SO₄was used as the water absorbing agent.The single factor experiments of feed ratio,reaction time and stirring speed were carried out.The single factor experiments were used to optimize the response surface.The optimal conditions were:temperature 55°C,pressure 8 MPa,ginger oleoresin:BMIm HSO₄（mass ratio）=1.05:1,time 8 min,stirring speed 200 rpm,under these conditions three parallel experiments were obtained.The average yield of 6-shogaol was 63.59%,and the experimental result was close to the predicted value,which verified the accuracy of the regression fitting model.The influence of experimental factors on the yield of 6-gingerol is:feed ratio>temperature>time.3.Establishing a new analytical method for 6-shogaol,6-,8-,10-gingerol by supercritical fluid chromatography,and comparing with the analytical methods of these four gingerol compounds established by the previous research group on HPLC,the analysis time of the new analysis method is about half of the latter,the content determination error of 6-,8-,10-gingerol in the same actual samples of the two analysis methods is less than 10%,and the content error of 6-shogaol is greater than 10%.