Analysis And Separation Of Volatile Components Of Mentha Haplocalyx

Mentha haplocalyx is a Chinese traditional medicinal materials and a good source of natural flavors and fragrances.It is widely cultivated in China and has good economic value.Therefore,it is very important to make a quality control for it and find an efficient way to separate and purify active ingredients from it.Volatile oil is an oily mixture with volatile extracted from aromatic and medicinal plants.It has the reputation of liquid gold because of its good biological activity.The volatile oil is the main component of Mentha haplocalyx,and its composition is comple Researchers used microwave or ultrasonic to assist steam distillation for improving the yield of oil,and used GC/MS combined with cluster analysis to summarize the chemical types of peppermint volatile oil.However,steam distillation is not an economical and efficient extraction method,and GC/MS has low resolution and sensitivity for the analysis of volatile oil.In this paper,GC×GC/TOFMS was used to analyze the components of volatile oils from different peppermint and compared with the result through GC/MS.Combined with principal component analysis(PCA),the chemical components of volatile oils from different production areas,parts and planting methods were classified,and the potential markers that had a great impact on the classification results were found.A more mild and effective method for extracting active components from peppermint,suspension particle assisted solvent sublation,were designed and established.And a high-speed countercurrent chromatography(HSCCC)method for separating and purifying active monoterpenes from peppermint volatile oil were established.The main research results are as follows:1.The volatile components in peppermint from different producing areas,parts and planting methods were extracted by steam distillation,the chemical components of different volatile oils of Mentha haplocalyx were identified by GC/MS and GC×GC/TOFMS,and the results were analyzed by PCA.The chemical composition information of 10 samples of volatile oil was obtained.Because of the orthogonal separation characteristics of the GC×GC separation system,the characteristic distribution on the GC×GC/TOFMS two-dimensional diagram was obtained.Through comparing the peak capacity and the number of substances detected by GC/MS and GC×GC/TOFMS,and the reconstructed 1D chromatogram of GC×GC/TOFMS with total ion chromatograms of GC/MS,and the two-dimensional time expansion diagram under the same one-dimensional time,GC×GC/TOFMS has higher sensitivity,higher resolution,higher accuracy and high efficiency in analyzing complex systems such as the volatile oils of Mentha haplocalyx.According to the results of principal component analysis,the 10 samples from different production areas were divided into three categories;the different components between stem and leaf of peppermint was found;the different components between wild and domestic varieties of peppermint was found.2.Suspension particle assisted solvent sublation was designed for the first time.The volatile monoterpenes in Mentha haplocalyx were separated by this method using the solution containing plant solid particles as the lower phase of solvent sublation.The optimized preparation procedure of suspension(solid-liquid ratio of 1:10(w/v))without ultrasonic treatment and salt was obtained.Under the optimum conditions of the solvent sublation(n-hexane/plant solid particles 20%ethanol-water solution system,pH 4,flotation time 30 min and air flow rate 30 m L/min),the extraction yields were 2.0×10~2 mg/kg,9.5×10~1mg/kg and 1.2×10~3 mg/kg for menthone,isomenthone and menthol,respectively.Compared with the traditional methods,the established suspension particle assisted solvent sublation is economical and efficient.Through cellular antioxidant activity experiment and molecular docking,menthol might have neuroprotective bioactivity and potential to be an amyloid-βinhibitor.3.A HSCCC method was established for the separation of monoterpenes from the volatile oil of Mentha haplocalyx.The optimal solvent system of n-hexane/acetonitrile(13:7,v/v)and high-speed countercurrent chromatography separation conditions(Injection weight:800.0 mg;Rotating speed:800 rpm;Flow rate:2 m L/min)were selected to separate two substances of menthol with purity of 85.1%and menthol acetate with purity of 94.2%.