Studies On The Preparation And Biological Activity Evaluation Of Cordycepin Liposome

Cordycepin, the main active constituent of Cordyceps militaris, possesses a wide range of biological activities, such as anti-tumor, anti-virus, antifungal and immunological regulation activity. However, it is difficult to be applied to clinical practices for the deamination of internal adenosine deaminase, which led to its deactivation. Using the adenosine deaminase inhibitor can easily cause human body immunodeficiency, the cost is too high if raising cordycepin dosage. Choosing new carriers of drugs to solve the deactivation of cordycepin has become an important direction. This text selected liposome as drug carrier to carry on primary study.In the study, we extracted coarse cordycepin from Cordyceps militaris by ethanol ultrasonic extraction method, the products were purified by column chromatography. The qualitative study was conducted by ultraviolet spectrum, infrared spectrum and high performance liquid chromatography analyses. Then, we studied the influence factors of phosphatidylcholine's extraction and determined the best extract condition. Phosphatidylcholine was extracted from soybean oilstocks with ethanol and acetone as solvents. Besides, the cholesterols were purified by recrystallization. Both finishedgoods were compared with the standard substances, the prepared phosphatidylcholine and cholesterols were both high purity sample.With home-made cordycepin, phosphatidylcholine and cholesterols as main starting materials, cordycepin liposome was prepared by reverse-phase evaporation successfully. The sample was characterized by Transmission Electron Microscopy, High Performance Liquid Chromatography and stability test. The result showed, it was ball-shaped, light yellow, the particle size was between 170nm and 350nm, the entrapment efficiency was 45%, and the liposome also had a good stability. This provided the necessary basic data for the cordycepin liposome research.The results of in vitro cell culture on cordycepin liposome confirmed that cordycepin liposome can effectively suppressed the cell proliferation of U937 tumour cell. Liposome's protective action can avoid the deamination of internal adenosine deaminase, enhance cordycepin's drug effects and decrease its effective dosage. When cordycepin concentration was 0.08mg/mL, the growth inhibitory rate of cordycepin liposome on tumor cell cultivated in vitro was 2.36 times that of cordycepin.