The Research Of Bioactivity And Physical Chemistry On Polysaccharide From Arthrobacter Sp.

A water soluble crude polysaccharide was extracted and precipitated by alcohol from zymolytic production of Arthrobacter sp. Protein was removed by trichloroacetic acid (TCA) method. The crude polysaccharide has been abstracted by the method of ethanol grading. Four fractions: APA,APB, APC, APD were obtained. No typical absorption of nucleic acid or protein was observed in UV spectrum, Infrared ray spectrum of APD indicates that it has typical characteristic absorption peaks of polysaccharides. We also tested the composition of the pollen polysaccharide by HPLC: both APB and APC polysaccharides mainly contained mannose and galactose; the APD polysaccharide contained glucuronic acid and galactose.APD was chemically modified by chlorosulfonic acid-pyridine method. APDS, a modified compound with 1.05 substituted degrees was obtained. The IR spectrum of APDS showed that characteristic absorptions of sulfate ester bond.We tested the anticancer activities of the polysaccharides APD and APDS by three kinds of cancer cell: BGC-823,HepG2 and A549 in vitro. Results from MTT bioassay showed that APDS inhibited these kinds of cancer cell remarkably,while APD had little cytotoxic activity towards the cancer cells . The inhibitory ratio of A549 was the highest, to 41.4%.The results of FCS and fluorescence indicted that the mechanism of APDS anti-tumor cell is not to induce the tumor cell to apoptosis.The results of immunocyte research showed that both APD and APDS could promote immunocyte and macrophage proliferation remarkably. They could promote the phagocytosis ability and production of NO. The polysaccharides and LPS together showed antagonistic action. Results in vivo showed that two polysaccharides could inhabit the growth of an S180 tumour remarkably in three doses. The highest inhibitory ratio of S180 tumour in middle dose was 35.69% and 38.19% respectly. All the results in vitro and in vivo showed that the polysaccharide APD and APDS inhabited tumour through enhancing the immunity, the polysaccharide APDS could inhabit tumour directly in addition.