The Studies On The Anti-tumor Activities Of Ginseng Polysaccharides Modified By Endo-polygalacturonase And High Temperature Treatment

Panax ginseng C.A.Meyer(P.ginseng)has been long used in China as traditional medicine for over 2000 years.P.ginseng contains many active components including ginsenosides,ginseng peptides and ginseng polysaccharides.It has been reported that the polysaccharides from P.ginseng had many activities,such as immunomodulating,anti-tumor,anti-adhesive,antioxidant and hypoglycemic activities,which is related to the structure.Other studies have also reported that the structure and activities of polysaccharides would be changed after modification.However,there are few reports focusing on the mechanisms.Therefore,we tested the structure and anti-tumor activity of ginseng polysaccharides modified with enzyme treatment and high temperature.The ginseng pectin(WGPA)was extracted from the roots of P.ginseng according to our previous method.WGPA was further hydrolyzed by endo-polygalacturonase to remove the un-esterified HG domain,then the hydrolysate was separated by dialysis to get WGPA-E-1 fraction which was identified RG-I.In vivo the inhibition of WGPA and WGPA-E-1 on growth of tummor was performed by inoculation of S-180 sarcoma cells into ICR mice.The results showed that the two fractions exerted inhibition on S-180 tumor growth,but WGPA-E-1 is better than WGPA.WGPA-E-1 can also stimulate both T and B spleen lymphocytes of tumor bearing mice,enhance the activity of macrophage phagocytosis and NO production.The results highlighted that RG-I can be obtained by treating ginseng pectin with enzyme,and the process is simple.WGPS which starh was removed from WGP was hydrolyzed by endo-polygalacturonase for 24 h to get WGPS-E-24,then was modified by high temperature twice to get HTWGPS-E-24,their sugar compositions are similar,but the molecular weight of WGPS-E-24 and HTWGPS-E-24 is lower than WGPS.In vitro the antitumor effects of all samples against S-180 cells were studied by MTT method.The order of inhibition rate was HTWGPS-E-24>>WGPS-E-24>WGPS>WGP.The polysaccharides modified by high temperature inhibite significantly the tummor cells directly and hence the growth of tumor.Anti-tumor and immune analysis in vivo were also processed(lymphocytes proliferation,macrophage phagocytosis and NO production).The results showed the HTWGPS-E-24 exerted significantly inhibition on S-180 tumor growth.It was also found to affect the immune function of tumor bearing mice,the antitumor activities of the fraction might relate to immune stimulation.The results of this paper can offer some datas about preparation methods of pectins,improved the application of pectin.