Study On Quality Evaluation Of Tibetan Medicine Strawberry(zhidasazeng)

This dissertation consists of five chapters.The first chapter mainly reports the textual research of Tibetan medicine strawberry.Through the integration of Tibetan medicine books,Chinese medicine monographs,national medicinal materials,botanical studies and modern literature.The name,basic source and sexual taste effect of Tibetan medicine strawberry were studied,and the main basic source of Tibetan medicine strawberry was determined to be 8 species of strawberry genus of Rosaceae,and one of the main basic sources of Tibetan medicine strawberry（Fragaria vesca L.）was selected as the main research object.The second chapter mainly reports the pharmacognosy research of Fragaria vesca L..The roots,stolons,stems,leaves,leaf epidermis and powder were identified by paraffin section.TLC identification of（+）-catechin and（-）-epicatechin as the reference,the development of the system of butyl acetate:formic acid:water=2:1:1（supernatant）as the development of the agent,the effect is obvious.In addition,according to the fourth part of 2020 Chinese Pharmacopoeia,the water content,ash content and extract content of 7 batches of Fragaria vesca L.were limited.The third chapter mainly includes two parts.The first part reports the separation of compounds from Fragaria vesca L..The ethanol extracts of Fragaria vesca L.were dissolved in water and precipitated,and then extracted in a system of polarity from small to large.After that through separation and purification method,get five compounds,the structural types were（+）-catechin（1）,ferulic acid（2）,β-sitosterol（3）,（-）-epicatechin（4）,quercetin-3-O-β-D-glucuronidoside（5）.In the second part,HPLC was used to determine the contents of（+）-catechin,（-）-epicatechin and quercetin-3-O-β-D-glucuronidoside in Fragaria vesca L..In this study,the solvent system of 1%formic acid aqueous solution（A）-methanol（B）was used as mobile phase,gradient elution.The content of（+）-catechin and（-）-epicatechin were respectively 1.1958 mg/g and 0.7155 mg/g at the detection wavelength of 280nm.The content of quercetin-3-O-β-D-glucuronidoside was 0.3020 mg/g at 360 nm.The fourth chapter consists of two parts.Firstly were the volatiles of Fragaria vesca L.herb were extracted by steam distillation and analyzed by GC-MS.In order to explore the composition of the volatile oil from the Fragaria vesca L.herb,the polarity of the volatile oil was compared with that of non-polar column（TR-FFAP and HP-5MS）.Then the extraction process was optimized by L₉（3⁴）orthogonal array.A total of 21 components were identified by TR-FFAP column and 11 components were identified by HP-5 MS column.The two groups of methods could complement the volatile components in Fragaria vesca L.more comprehensively.The orthogonal test results showed that the volatile oil yield and the relative content of the target product were the highest when the Fragaria vesca L.powder was soaked in 10 times of water for 2 h and then extracted by reflux for 6 h.the extraction conditions of total polyphenols from Fragaria vesca L.were investigated by single factor experiment,and the extraction process was optimized by orthogonal design of L₂₅（4⁵）.The optimal results were as follows:when the ratio of solid to liquid was 1:14,the total polyphenols of wild strawberry powder were extracted by 80%ethanol at 70℃for2.5 h.Under these conditions,the content of polyphenols in Fragaria vesca L.was74.15 mg/g.Then,the biological activity of total polyphenols was studied by DPPH radical scavenging assay.The results showed that the scavenging rate of DPPH was the highest in the 2.0～3.4 g/m L polyphenols in Fragaria vesca L and the scavenging rate was stable at 94.49%.The antioxidant activity of the total polyphenols of Fragaria vesca L.was 14 times that of Vc and 3 times that of（+）-catechin.The fifth chapter mainly reports the geographical traceability of Tibetan medicine strawberry.By combining the data of HPLC and ICP-MS with the data of single technique,and combining with the pattern recognition method,the geographical traceback research was carried out on the medicinal materials of Fragaria orientalis Lozinsk from five producing areas of Xizang,Hebei,Inner Mongolia,Sichuan and Yunnan.HPLC was used to establish the fingerprint of Fragaria orientalis Lozinsk,and LC-MS was used to assign the composition of each chromatographic peak,and the information of chromatographic peak was used as dataset 1.The contents of 21kinds of inorganic elements in Fragaria orientalis Lozinsk were determined by ICP-MS,and the fingerprint of inorganic elements was established by logarithmic method.The information of inorganic elements was taken as data set 2.The two data were fused as dataset 3.CA,PCA,PCA-LDA and C5.0 decision tree algorithms were combined to compare the geographical traceability results of the three data sets.The results showed that CA,PCA and PCA-LDA of the data fusion method could correctly classify 96 batches of Fragaria orientalis Lozinsk.The PCA-LDA model of data fusion method was validated internally and externally,and the correct classification rate was more than 88.3%.Four major contributing variables were selected from the C5.0 decision tree,and the classification rule with tree depth of 3was obtained.The accuracy of the decision rule is 98.9%after 10-fold cross verification.The data fusion method can improve the accuracy of geographical traceability of Fragaria orientalis Lozinsk from different origins,and the classification rules obtained by decision tree algorithm can reduce the difficulty of actual operation,which is conducive to the quality control of Fragaria orientalis Lozinsk,and also provides reference for the traceability of other medicinal materials.