Structural Analysis And Antioxidant And Anti-bacterial Activities Of Polysaccharides From Ferula Sinkiangensis

Ferula Sinkiangensisis a kind of precious traditional Chinese medcineand has various pharmacological activities,such as preventing further attack of malaria,antiallergic,expectorant and promoting blood circulation.At present,the studies on active ingredients from Ferula Sinkiangensis mainly focus on resins,gums and volatile oil.The study on polysaccharide structure,espectically for fine structure of pectin polysaccharides is scarce.Therefore,in this study,Ferula Sinkiangensispolysaccharides were extracted by different solventsin sequence to obtain four crude polysaccharides FSP-C,FSP-H,FSP-O and FSP-S.The physicochemical propertiesof these polysaccharides were investigated and separation of FSP by chromatography fractionation to prepare different pectic domains and studied their structure information;at the same time,prepared the pectic domains(which mainly contained RG and AG)by enzymic hydrolysis and chromatographyfractionation,and their structure were studied.FSP was separated and fractionated by chromatography methods to prepare several pectin fractions(mainly contained RG and AG).These pectin fractions were further hydrolysed by enzyme for molecular structural information study.Ferula Sinkiangensisroots were sequentially extracted with cold water,hot water,oxalic acid solution and sodium hydroxide solution.Four polysaccharide fractions FSP-C,FSP-H,FSP-O and FSP-S were obtained with the yield of 5.9%,9.5%,8.0% and 9.6%,respectively.FSP-H has the highest yield Finally,hot water extraction method was optimized by using the orthogonal test design.According to the normal separation procedure in our lab,FSP was firstly separated using a DEAE-cellulose column to obtain the FSPN(neutral fraction)and the FSPA(acidic fraction).Then FSPA was fractionated by using DEAE-cellulose,Sepharose CL-6B and Sephacryl S200,gettingfour different pectin factions FSPA-1-A,FSPA-1-B,FSPA-2-A and FSPA-2-B.They mainly contained of GalA,Rha,Gal and Ara.FSPA-1-B contained some methyl groups and FSPA-2-A contained some acetyl groups.FT-IR and NMR spectra analysis showed that FSPA-1-A mainly contained AGI and AGII domains which were connected to a shorter RGI domain;FSPA-1-B contained the HG and RGI domain with AGI side chains;FSPA-2-A mainly contained the AGI domian which was connected to a shorter RGI domainand FSPA-2-B was a typical RGI domain.Furthermore,FSPA was enzymatically hydrolyed using Endo-PG to remove HG domians and then fractionated by DEAE-Sepharose Fast Flow,Sephadex G75 and Sephacryl S200 columns,giving twohomogeneous fractions,which both mainly contained the RGI domain.In addtion,the antioxidant activities of FSP-C,FSP-H,FSP-Oand FSP-S was investigated by various antioxidant assay in vitro systems,including DPPH radical scavenging,and reducing power.The results indicated that antioxidant activities of purification polysaccharides increased with an increased amount of samples.Among these fractions,FSP-C,FSP-H and FSP-S showed strong antioxidant activities,with IC50 valuesof 0.783 mg/mL,0.595 mg/mL and 0.321 mg/mL,respectively.The antibacterial activities of these samples were also investigated.The results showed that FSP-C,FSP-H,FSP-O and FSP-S all had antibacterial activities with different levels.