Study On The Structure And Activity Of Seabuckthorn Proanthocyanidins With Different Degrees Of Polymerization

Proanthocyanidins are a class of polyphenolic compounds,with a strong antioxidant effect,and it is widely used in anti-aging,regulating blood pressure,blood lipids,anti-tumor and other health foods.Seabuckthorn's?Hippophae rhamnoides Linn.?leaf and fruit contains rich of flower pigment.Many studies have shown that,in degree of polymerization,proanthocyanidins extracted from natural plants have many differences,and the degree of polymerization and antioxidant activity are related closely.In different plant organs,the activity of proanthocyanidins are very different,as well as the proanthocyanidins are degraded in different ways.Therefore explore the proanthocyanidins higher degree of polymerization activity is important for the application of proanthocyanidins.This experiment got differents degree of polymerization of the proanthocyanidins by different methods.We also studied the activity of it,and analyzed the its initial structure,so this work is very meaningful to explore the relationship between the degree of polymerization and the activition of proanthocyanidins.Different degree of polymerization of proanthocyanidins obtained.By ultrasonic extraction of proanthocyanidins from sea buckthorn different organs?sea buckthorn sea buckthorn seed and leaf?,purified to obtain high polymer proanthocyanidins,and then separately with the chemical degradation method?sulfite degradation?and microbial degradation?D.dasht purple Penicillium degradation method?extracted from sea buckthorn proanthocyanidins degradation,obtained after purification 8 different degrees of polymerization of proanthocyanidins,respectively 10.6,5.8,3.6,3.1,2.8,2.3,1.8,1.2 polymerization degree.Activity of different degree of polymerization of proanthocyanidins.Different degrees of polymerization of sea buckthorn proanthocyanidins superoxide anion inhibition of nitrite ion scavenging of DPPH free radical scavenging and to analyze its antioxidant capacity,the result is:the lower the degree of polymerization of sea buckthorn proanthocyanidins inhibition of superoxide anion,nitrite ion scavenging and scavenging of DPPH radical were the stronger;the degree of polymerization of proanthocyanidins of sub 1.2 scavenging nitrate ions is the highest of all components,up to 98%.Structural different degree of polymerization of proanthocyanidins.Using infrared spectroscopy,mass spectrometry,nuclear magnetic resonance methods for the different degree of polymerization of sea buckthorn proanthocyanidins were structural analysis,infrared spectra indicate that the number of low degree of polymerization of proanthocyanidins CH₂ and hydroxyl groups increased significantly,indicating that bond breaking proanthocyanidins between units,resulting in lower polymerization degree,since the phenolic hydroxyl group is superoxide anion,DPPH radical and the main active groups nitrite ions,the lower the degree of polymerization of proanthocyanidins,proanthocyanidins link monomer will break chemical bonds,causing their effective phenolic hydroxyl contacting the reactants with the relative probability increases,therefore its ability to remove superoxide anion,for scavenging nitrite ions,scavenging effects on DPPH radical enhancement.Mass spectrometry analysis,determination of degree of polymerization of 5.8,2.3,1.2 molecular weight,molecular weight of the smallest 308.123.After NMR analysis,CH2 signal peaks and hydroxyl signal peaks lower degree of polymerization of proanthocyanidins stronger,which is consistent with the results of the infrared spectrum,the number of hydrogen also decrease with increasing degree of polymerization.The lower the degree of polymerization of sea buckthorn proanthocyanidins,contact probability of its effective phenolic hydroxyl reactant relative increase,a phenolic hydroxyl group can effectively scavenge superoxide anion,nitrite and DPPH radicals.