The Extraction, Isolation, Purification Of Astragalus Polysacch Arides And The Research On Its Biological Activity

Astragalus membranaceus is used as a Chinese herbal medicine.It containspo lysaccharides, protein, alkaloid, amino acid, flavonoids, glycoside, trace ele ment etc. Astragalus polysaccharides (APS) is main biological active compone nt. APS have morepharmacol-effects,such as,immunomodulation,lowerblood suga r,anti-stress,anti-tumor,antivirus, antiradiation,antioxidation etc.APS have been th e focus on extrcation of the traditional Chinese medicine and the modern rese arch of Chinese herbal medicine.Macrophages play a significant role in the host defense mechanism. And it is the key participants in the innate immune response.When activated they i nhibit the growth of a wide variety of tumor cells and microorganisms.In addi tion,macrophages can function as antigen-presenting cells and interact with T 1 ymphocytes to modulate the adaptive immune response . Furthermore, macroph ages are involved in tissue remodeling during embryogenesis, wound repair, cl earance of apoptotic cells and hematopoiesis.Most investiments showed that APS have immunomodulatory effects.But r esearch on stimulating function of APS to macrophage was very few and the study object was total APS.Here we managed to cultured macrophage be direc tly influenced by every fraction of APS ,then measured the changes of gene transcription and translation level of IL-1 P ,TNF- a and GM-CSF,respectively b y methods of ELISA.In addition ,we treated mouse with every fraction of AP S and measured the changes of gene transcription and translation level of IL-1 P ,TNF- a and GM-CSF, respectively by ELISA.The preparation showed that APS can be separated to three parts (<30,0 00,30,000-50,000 and >50,000) by ultrafiltration ,the quantity of APS was 1.4 g, 1.6g, 1.45g and the purity was 50%,70%,81%.The purity of the two parts(3 0,000-50,000 and >50,000)was high.ELISA results showed that 30,000-50,000, above 50,000 and total APS ca n enhanced the secretion of IL-1 P in macrophage,and the 30,000-50,000 APS can enhanced the secretion of TNF- a and GM-CSF in macrophage.Conclusively,our experiments indicated that the method of ultrafiltration can be used to separate and depurate APS.The production of ultrafiltration, e specially the 30,000-50,000 parts of APS, can inhance the secretion of IL-1 P , TNF- a and GM-CSF in macrophage.