Research On Extraction And Antioxidant Activity Of Polysaccharides From Notoginseng And Ginseng In Different Parts

In this study,the extraction,isolation and purification,physicochemical and structure properties and antioxidant activities of polysaccharides from the stem leaf and flower of panax notoginseng and Ginseng have been researched,and the results are as follows:1.Ultrasonic extraction（UE）of crude polysaccharides（CRPNP）from panax notoginseng root and crude polysaccharides（CFPNP）from panax notoginseng flower was optimized by response surface methodology（RSM）.Under the optimal extraction conditions,the CRPNP and CFPNP yield was 5.46%and 2.72%,respectively.Then two fractions（RPNP-1 and RPNP-2）of CRPNP and two fractions（FNP-1 and FNP-2）of CFPNP were obtained by precipitated with ethanol,removed protein with the Sevag method,decolorized using H₂O_2,dialyzed against water to remove small molecule ingredients,and purified using DEAE-Sepharose Fast Flow anion-exchange and Sephadex G-100 gel filtration chromatography,respectively.The physicochemical characterizations of fractions were investigated by high performance gel permeation chromatography（HPGPC）,gas chromatography（GC）,fourier transform infrared spectroscopy（FT-IR）and ultraviolet-visible spectroscopy（UV）.RPNP-1 was a heteropolysaccharide containing uronic acid（3.12%）and protein（1.65%）,with average molecular weights of 246389 Da,which mainly consisted of rhamnose（Rha）,arabinose（Ara）,xylose（Xyl）,mannose（Man）and glucose（Glc）.RPNP-2 was a heteropolysaccharide containing 5.15%of uronic acid and 1.84%of protein,with average molecular weight of 22490 Da,which mainly consisted of Rha,Ara,Xyl,Man,Glc and galactose（Gal）.Infrared spectroscopy data revealed that RPNP-1 and RPNP-2were constituted of functional groups O-H,C=O and C-H which were specific to polysaccharides.FPNP-1 was a heteropolysaccharide containing uronic acid（3.18%）and protein（1.16%）,with average molecular weights of 11749 Da,which mainly consisted of Man,Rha,GlcA,GalA,Glc,Xyl,Gal and Ara.FPNP-2 was a heteropolysaccharide containing 4.12%of uronic acid and 2.28%of protein,with average molecular weights of 5888 Da,which mainly consisted of Man,Rha,GlcA,GalA,Glc,Xyl,Gal and Ara.Infrared spectroscopy data revealed that FPNP-1 and FPNP-2 were constituted of functional groups O-H,C=O and C-H which were specific to polysaccharides.Furthermore,the antioxidant effects of fractions upon FRAP,?DPPH,?OH and?O₂^-scavenging assay,were investigated.The results indicated that RPNP-1,RPNP-2,FPNP-1 and FPNP-2 possessed significant antioxidant effects in a concentration-dependant manner in high FRAP and strong scavenging activity against DPPH?,?OH and?O₂^-.2.Ginseng root,ginseng flower and ginseng leaf polysaccharides were extracted by UE,the crude ginseng root polysaccharide（CRGP）,ginseng flower crude polysaccharide（CFGP）and ginseng leaf crude polysaccharide（CLGPG）were obtained by precipitated with ethanol,removed protein with the Sevag method,decolorized using H₂O₂,dialyzed against water to remove small molecule ingredients,and purified using ultrafiltration membranes and Sephadex G-100 gel filtration chromatography,respectively.Five homogeneous polysaccharides CRGP with different molecular weight distributions（RGP-1,RGP-2,RGP-3,RGP-4 and RGP-5）,four homogeneous polysaccharides CFGP with different molecular weight distributions（FGP-1,FGP-2,FGP-3 and FGP-4）and three homogenous polysaccharides of ginseng leaves（LGP-1,LGP-2 and LGP-3）were obtained,respectively.The average molecular weight of polysaccharides was determined by HPGPC,the protein content of different parts of ginseng was determined by Coomassie brilliant blue method,and the uronic acid content of polysaccharides from different parts of ginseng was determined by sulfuric acid carbazole method.The main components of polysaccharides with different molecular weight in ginseng root were Glc,Xyl,Gal and Man,among which the content of Gal was higher,and the four polysaccharides of ginseng flower were mainly composed of Glc and Xyl,Gal and Man,among which Gal was the main monosaccharide component,ginseng leaf polysaccharide is composed of Glc,Xyl,Gal and Man,among which the content of Gal was higher.The results of UV and FT-IR spectra showed that all the polysaccharides had the characteristic absorption peaks of polysaccharides.Furthermore,the antioxidant effects of fractions upon scavenging assay,were investigated.The results of FRAP,?DPPH,?OH and?O2 scavenging ability of each polysaccharide component showed that all polysaccharides had strong iron ion reduction ability and free radical scavenging activity,and there was a good dose-effect relationship between concentration and activity.These polysaccharides all have obvious antioxidant activity.The effect of extraction conditions,time and yield considered,concluded that the ultrasonic extraction method is better.In the samples studied,the content of polysaccharide of CRGP was higher than that of CGPNP and CLGP,the content of polysaccharide of CFPNP is the lowest.The results indicated that five plant polysacchrides possessed significant antioxidant effects in a concentration-dependant manner,which can be utilized as medicine and natural antioxidant.