1. Source: from Chinese Cobra Venom 2. Description: 3. Mol wt: 7,400~7,500 4. Identification of biological activity: It has been approved by MTT that the Cytotoxin抯 execution degree in vitro cultivated tumour cells can be used as its index of anti-tumour activity. 5. Usage fields: Cytotoxin has extensive biological activity; it has destruction function to animal trail tumour cells in vitro cultivate experiment while little effect to normal cells both in human and animals. This is very important in tumour treatment because it can greatly reduce druggy poison side-effect to tumour sufferers.