Study On The Extraction And Purification Of Alkaloid 4(3H) Quinazolinone From Folium Isatidis

Folium Isatidis is a common traditional Chinese herbage in the nation, which is widely used for curing febricity diseases such as fever dipsosis,hematemesis,and aurigo etc. It is bitter in flavor and chilly in nature,possessing multiple functions in vivo, including repression of overheating,detoxication,cooling blood and removing ecchymoses. The pharmacological studies show that 4(3H)quinazolinone ,one of the major components of Folium Isatidis, has antibacterial, antiviral, antihypertensive, antihyperlipidemic, antihypercholesterolemic activities. However, few studies have been made yet on the purification and production of this chemical from Folium Isatidis.The present study sought to develoge and optimize the technology of extraction and purification of 4(3H)quinazolinone from Folium Isatidis for its further characterigation.The results of this study show:1.The contents of 4(3H)quinazolinone are used as index to conduct percolation, heat reflux, ultrasonic and microwave extraction screen for the optimal conditions by orthogonal test whose factors are materials size,extractant concentration, extraction time and solvent volume on the extraction of 4(3H)quinazolinone. In the first experiment of percolation extraction,the optimal conditions are soak for 24h in 8 times of 50% alcohol at 2ml/min.In the second,the optimal conditions are soak for 12h in 16 times of pure methanol at 4ml/min.In the first experiment of heat reflux extraction,the optimal conditions are scatter medical materials(particle size:60) with 8 times of 70% alcohol and last for 1h.In the second,the optimal conditions are scatter medical materials(particle size:60) with 8 times of pure methanol and last for 3h. In the first experiment of ultrasonic extraction,the optimal conditions are scatter medical materials(particle size:80) with 8 times of 70% alcohol and last for 20min.In the second,the optimal conditions are scatter medical materials(particle size:60) with 9 times of pure methanol and last for 40min.In the first experiment of microwave extraction,the optimal conditions are scatter medical materials(particle size:40) with 10 times of 50% alcohol and last for 10min. In the second,the optimal conditions are scatter medical materials(particle size:20) with 20 times of pure methanol and last for 5min.By comparison of above four kinds of extraction processes,the second experiment of heat reflux extraction is the best in extractional rate of 4(3H)quinazolinone.The optimal conditions are scatter medical materials(particle size:60) with 8 times of pure methanol and last for 3h. Since pure methanol's toxicity is strong,it is only suitable for the few extractions in the laboratory.According to direct-viewing analysis obtained from orthogonal experiment of the second experiment of heat reflux extraction, pure alcohol for the extraction is more advisable.2. In separation of 4(3H)quinazolinone from Folium Isatidis by Organic Solvent Extraction, Ph value has an tremendous influence on Chinese herbal extractions. When the pH value is 1,the extraction is best in the experiments of adjusting acid.When the pH value is 9,the extraction is best in the esperiment of adjusting base. Under the best pH condition, the content of 4(3H)quinazolinone is 3.52% in the extraction from Folium Isatidis. 3.The silica gel column chromatography is used to separate and purify the monomer of 4(3H)quinazolinone from Folium Isatidis.Through IR spectra,HPLC-MS and NMR,the monomer is identified as 4(3H)quinazolinone.The purity of 4(3H)quinazolinone analyzed by HPLC is 95.7%.