Extraction,Separation And Purification Of Z-ligustilide With Neuroprotective Effect In Chuanxiong

The number of patients suffering stroke is increasing with the improvement of diet,the acceleration of life rhythm,the increase of working pressure and irregular living habits,which is one of the three major diseases leading to human death and disability.At present,there is still a lack of effective medicine and therapeutic targets for the treatment and rehabilitation of stroke or/and its sequelae.Strikingly,the clinical practice shows that traditional Chinese medicine has fascinating advantages in the treatment and rehabilitation of stroke.Ligusticum chuanxiong is a traditional Chinese medicine with a long history of promoting blood circulation and removing blood stasis.It is a commonly used traditional Chinese medicine in the treatment of cerebral apoplexy,hemiplegia,hemp,language disadvantage and other diseases.Ligusticum chuanxiong harbors high percent ligustilide that belongs to phthalide compounds,and is divided into Z-ligustilide(Z type)and trans-ligustilide(E type),Ligusticum chuanxiong mainly contains Z-ligustilide.Z-ligustilide has the effects of promoting blood circulation and removing blood stasis,neuroprotective effect,inhibiting proliferation of vascular smooth muscle,maintaining vasodilation,antioxidation,anti-wrinkle,relieving muscle clonus and so on.However,the thermal instability of ligustilide limits the further research and development of ligustilide as a new natural medicine.Therefore,in this thesis,the act ive monomer of ligustilide was extracted,separated and purified by column chromatography at room temperature,which laid a material foundation for the further study of its stability and the pharmacological mechanism of nerve protection from injury.In this study,Ligusticum chuanxiong was used as raw material of traditional Chinese medicine,ligustilide was extracted by column chromatography by using Z-ligustilide as extraction index.The effects of extraction solvent,soaking time and extraction dosage on the extraction rate of target components were investigated systematically.The optimum conditions for column chromatography were as follows: Ligusticum chuanxiong was smashed and passed sieve of 20-80 mesh,petroleum ether-95% ethanol(6:4,V:V)solution was added according to the ratio of dry weight of 1.6ml/g material,loaded into chromatography column and kept at room temperature for 3 hours.The extract was eluted with petroleum ether-95% ethanol(6:4,V:V)at room temperature.the flow rate was 1.0 MV/h(MV is the saturated absorption volume of the material,which is the minimum volume unit of the extract).The extraction rate of ligustilide was more than 97% when the collected extract solution was 3.2 times of the dry weight of the material.The amount of extracting material was amplified 100 times in proportion,and the results were consistent with the small scale test,and had good repeatability.The condition of purification of Z-ligustilide by extraction and silica gel column chromatography was optimized.The optimum process for purifying Z-ligustilide is as follows: the extract solution was extracted once with 1/3 volume pure water,1/10 volume pure water and 1/10 volume petroleum ether twice,The crude product of Z-ligustilide was obtained after petroleum ether phase combined with decompression and concentration.After separated and collected by silica gel column chromatography,the eluent was removed by decompression,dissolved with 10 times the volume of petroleum ether,adsorbed and centrifuged with half the volume of silica gel,and the purity of the product was higher than that of the standard of Z-ligustilide.In this thesis,a new technological process for extraction,separation and purification of ligusticum lactone from Ligusticum chuanxi ong was established.The extraction method is carried out at room temperature,the operation is simple,the amount of extraction solvent is small,the extraction efficiency is high,and the separation and purification steps are few,so it is an ideal metho d for the preparation of pure Z-ligustilide.The pure product obtained by this method can be used to study the pharmacological mechanisms of the neuroprotective activity of Ligusticolide further.