Study On The Series Of Pectin Products Of Sunflower

Sunflower head is a solid,residual by product of sunflower seed oil produced.There is the amount of sunflower heads in China.It is a significant popular due to the presence of large amounts of poly-phenols,polysaccharides,pectin and other organic substances,it will be used widely in food and pharmaceutial industries.Sunflower held were used as the research object in the study.Pectic oligosaccharide and low molecular weight pectic ploysaccharide were produced by hydrochloric acid extraction and further pectinase enzymatic hydrolysis.The extraction,isolation,purification,physical-chemical properties,structural elucidation of low molecular weight pectic ploysaccharide,the anti-bacterial activity of pectic oligosaccharide and the silage fermentation of sunflower held grounds extracted pectic oligosaccharide were researched systematically and deeply in this paper.It finds a comprehensive utilization of sunflower and develop high value-added product routings.The dissertation mainly was divided into four parts.Researches on the preparation of pectic oligosaccharide and low molecular weight pectic ploysaccharide,the extraction,isolation,purification,physical-chemical properties,structural elucidation of low molecular weight pectic ploysaccharide,the anti-bacterial activity of pectic oligosaccharide and the silage fermentation of sunflower held grounds extracted pectic oligosaccharide were discussed in this paper.The results were as follows:(1)By single factor and orthogonal test draw the optimal condition of pectinase B by hydrochloric acid extraction and further pectinase enzymatic hydrolyzing in sunflower held were:enzyme dosage 2.4 U/g,substrate concentration 6.5%,hydrolysis temperature 50?,hydrolysis time 8 h and pH value 5.0.Under this condition he yield of pectic oligosaccharide 54.5%,which were 14.3%and 7.6%higher than that of sunflower held extraction used pectinase B to hydrolyze and pectinase A by hydrochloric acid extraction and further pectinase enzymatic hydrolysis,respectively.Based on the optimal combination,the enzymolysis time is set to 3h for preparation of low molecular weight pectin,the extraction rate was 7.24%.(2)Low molecular weight pectin hydrolysate was selected for further study and purified with ion exchange chromatography on DEAE-Sepharose fast flow.And two major elution peaks:LMPW and LMPS,were detected.Then LMPS was further purified by High Resolution Sephacryl S-200 gel-permeation chromatography,and a major polysaccharide named as SHPPB-1 was isolated.SHPPB-1 appeared as a single symmetrical peak in the HPLC chromatograph,indicating that SHPPB-1 was a homogeneous polysaccharide,with an average molecular weight of 1.69×10~4 Da.The results of UV scanning indicated that SHPPB-1 didn't contain protein but trace amount of nucleic acid.The structure characterization of SHPPB-1 was elucidated by IR,GC-MS analysis and NMR spectrum analysis.SHPPB-1 was hydrolyzed with TFA,derivatived with PMP and HPLC analysis indicated that SHPPB-1was composed of D-galactose,L-rhamnose,D-mannose,D-galacturonic acid and fare D-xylose,D-glucose and L-arabinose,The IR,methylation analysis and NMR analysis showed that the primary structure of SHPPB-1 mainly consisted of?-D-2-OAc-6-OMe-(1?4)-GalpA backbone and?-D-(1?4)-GalpA as the backbone and branched at O-2and O-3 positions with t-GalpA,t-Rhap or t-Manp,and with a few3,4-GalpA.(3)By controlling the hydrolysis conditions,the sunflower pectin were further hydrolyzed into lower molecular weight pectin oligosaccharides.Then the yeast fermentation were used to remove low sugar solution of monosaccharide in solution,and different degree of polymerization of pectin oligosaccharides were obtained by ultrafiltration membrane filter.Comparated to antibacterial activity of sunflower head pecticoligosaccharide(SPO)andcitruspectic oligosaccharide(CPO)againstEscherichiacoli,Staphylococcus aureus and Bacillus subtilis.It is showed that the antibacterial activity of CPO against Escherichia coli and Bacillus subtilis is higher than that of SPO,but the antibacterial activity on Staphylococcus aureus was lower than SPO.The polymerization degree of 15-50 SPO was higher inhibitory activity,the minimum inhibitory concentration of the SPO and CPO against three kinds of bacteria was 0.06-0.6mg.(4)The sunflower head grounds was inoculated Lactobacillus plantarum and Lactobacillus to fermentate.The fermentation results showed that the fermentation of sunflower head grounds can not only achieve the standard of silage,after adding bran and other organic matter canimprovethe fermentationqualityofsilage,to achieve the standard of high quality silage.