Study On The Extraction And Separation Process Of Polyprenol From Ginkgo Biloba Extract Production Waste

Objective:Ginkgo biloba leaves mainly contain flavonoids,lactones,polypentenols and other active ingredients.The research on flavonoids and lactones has been relatively mature,and related preparations are widely used in the treatment of cardiovascular and cerebrovascular diseases.In the production process of Ginkgo biloba extract（GBE）,the water-soluble components were extracted by alcohol,while the fat-soluble components,such as polyprenols,were discarded as wastes,which resulted in a certain waste of resources.The effective disposal of waste from industrial production of GBE has become an urgent problem in the development of the industry.Through the study on the extraction and separation process of polyprenols in the industrial production waste of GBE,the enrichment of high-purity polyprenols was obtained,so as to carry out relevant research,which can improve the utilization rate of Ginkgo biloba resources,achieve the purpose of secondary development and green environmental protection,and conform to the concept of circular economy and green development.It provides a research basis for the treatment scheme of"three wastes"in the production of traditional Chinese medicine.Methods:In this study,polyprenols homologue was used as the target compound,and the content of polyprenols was determined by high performance liquid chromatography（HPLC）.The extraction,separation and purification process were investigated.The main research methods were as follows:（1）Establishment of a method for the determination of polyprenols in Ginkgo biloba leaves and screening of waste points:A HPLC method for the quantitative determination of polyprenols in Ginkgo biloba leaves was established,and the methodology was investigated.The waste sites of GBE were screened.（2）Establishment and optimization of the extraction process of polyprenols from Ginkgo biloba leaf residue:ultrasonic extraction method,reflux extraction method and supercritical CO₂ extraction method were compared with the extraction rate（content）of polyprenols as the index;The ultrasonic extraction method was optimized by single factor experiment,uniform design experiment and solid-liquid ratio optimization experiment to determine the best extraction process.（3）Separation,purification and identification of polyprenols from Ginkgo biloba leaf residue:Taking the purity and recovery of polyprenols as indicators,polyprenols were separated and purified by acetone freezing dewaxing,mixed decolorization agent decolorization and silica gel column chromatography.The silica gel column chromatography was used for single factor investigation to determine the best separation and purification process.The purified products were identified by liquid mass spectrometry（LC/MS）.Results:To establish a HPLC method for the quantitative determination of polypretenol,the column temperature was 30℃,the flow rate was 1 m L/min,the sample size was 10μL,isopropanol-methanol（55:45）iso-elution,and the detection wavelength was210nm.The waste points of Ginkgo biloba leaf extract were screened and polypentenol was found in the alcohol extraction residue of Ginkgo biloba leaves.To gather pentene alcohol content（%）as an index,compare the three different extraction methods,ultrasonic extraction method of single factor experiment,eventually uniform design experiment and solid-liquid ratio optimization experiment,polyprenols best extraction process is:material liquid than 1:5,ultrasonic temperature 30℃,60 min ultrasonic time,ultrasonic power 200 w,repeat twice.With the purity（%）and recovery（%）of polypentenol as indexes,acetone freezing dewaxing,mixed decolorization agent decolorization,silica gel column chromatography separation were conducted successively,and the single factor investigation on silica gel column chromatography was carried out,and the optimal conditions were obtained as follows:The silica gel particle size was 200-300 mesh,the loading ratio was 1:65,and the diameter to height ratio was 1:5.The gradient elution was carried out by petroleum ether and 1%-3%ethyl acetate-petroleum ether successively,and the flow fraction containing polyprenols was collected to obtain the purified product,which was identified as polyprenols homologue by LC/MS identification.Conclusion:In this paper,the preparation process of polyprenols extraction and purification was established.The process is stable,feasible,simple equipment,and has a prospect of industrial production and application.This topic will be the production of GBE industrial waste polyprenols for secondary recycling,waste,improved the waste additional use value,for the green production of GBE and gingko provide reference for the development of the recycle of resources,for traditional Chinese medicine in the industrial production of"three wastes"treatment scheme to provide research basis.