Application Of Chromatographic Fingerprinting And Dummy Template Molecularly Imprinting In Natural Products’ Separation And Analysis

Currently,most of the known active ingredients of natural products（NPs）have good medicinal activities,such as anti-cancer,anti-inflammatory,anti-ageing and anti-oxidant properties,and are of great value in the field of medicine.NPs in medicinal plants are complex and scarce,and require high separation,sensitivity and precision to achieve enrichment,characterization and quantitative analysis of the active ingredients,so it is of great interest to develop new chromatographic techniques for the separation and analysis of NPs in complex matrices.Molecularly imprinted solid phase extraction is a promising separation technique for the determination of actual plant samples with medicinal value,as a novel extraction technique combined with sensitive high performance liquid chromatography（HPLC）.In this paper,HPLC was chosen to analyse the complex and valuable active ingredients of Coreopsis tinctoria,and the HPLC fingerprints were combined with the antioxidant activity to establish the spectroscopic relationship and to demonstrate the antioxidant efficacy of the common components in Coreopsis tinctoria.The combination of MIPs and solid-phase extraction allowed for the efficient separation and enrichment of ellagic acid,which has high medicinal value in pomegranate peel.The main studies were as follows:（1）To complete the identification of 10 batches of Coreopsis tinctoria from different origins and different harvesting periods,HPLC was used to establish fingerprint profiles of Coreopsis tinctoria,screen the common components and evaluate the similarity,the results showed that the similarity of the herbs from different origins of Coreopsis tinctoria was greater than 0.9000,indicating that the quality of Coreopsis tinctoria was consistent;systematic cluster analysis and principal component analysis were used for chemical pattern identification,all of which classified Coreopsis tinctoria into four categories.The chemical pattern identification using systematic cluster analysis and principal component analysis both classified Coreopsis tinctoria into four classes,of which S4～S7 and S10were one class,S1,S8 and S9 were one class,S2 was one class and S3 was one class.The above results provide a more scientific and reasonable evaluation of the quality of Coreopsis tinctoria and provide a basis for ensuring clinical efficacy.In order to obtain the spectrum-effect relationship between the HPLC fingerprint and antioxidant activity of 10batches of Coreopsis tinctoria,the antioxidant activity of 10 batches of Coreopsis tinctoria was determined by using 1,1-diphenyl-2-trinitro-phenylhydrazine,2,2-benzo-bis（3-ethyl-benzothiazole-6-sulfonic acid）diammonium salt free radical scavenging method,and the results showed that Coreopsis tinctoria of origin S8 had the strongest antioxidant capacity The results showed that in the DPPH radical scavenging method,the common components that contributed more to the strong antioxidant activity of the samples（correlation greater than 0.800）were 20,1,7,21,24,and in the ABTS radical scavenging method,the common components that contributed more were 14,24,23,1,11,in order.The results screened out the active fractions in Coreopsis tinctoria that contributed mainly to the antioxidant efficacy and provided a reference for the antioxidant spectrum-effect relationship and pharmacological studies of other medicinal plants.（2）In order to achieve the enrichment of ellagic acid,the MIPs were synthesized by reversible addition-breakage chain transfer radical polymerization using cheap and easily available gallic acid as a virtual template,and the MIPs were characterized by FT-IR and SEM.The adsorption properties of MIPs were evaluated by Scatchard analysis,adsorption isotherms and adsorption kinetics.The results showed that there were two different binding sites with high and low affinity for MIPs,and the saturation adsorption amount was 4226μg·g^-1 for the high affinity site and 1098μg·g^-1 for the low affinity site.The results showed that the MIPs were successfully prepared and exhibited good adsorption performance on ellagic acid and could be used for the enrichment and separation of ellagic acid.Separation.In order to investigate the adsorption effect of MIPs on ellagic acid in real samples,MIPs were used as solid phase extraction sorbents for the adsorption and enrichment of ellagic acid from pomegranate peels.The results showed that the concentration of ellagic acid in the initial sample solution was 36.91μg·m L^-1;after extraction,the concentration of ellagic acid was 7.31μg·m L^-1;after elution,the concentration of ellagic acid was 33.25μg·m L^-1,yielding a recovery of ellagic acid of 90.1%.The above results indicate that the material can achieve the separation and enrichment of ellagic acid in complex matrices,providing a reference for the separation and analysis of other active components with medicinal value.