| Based on the review of processing history and modern literature, the author systematically studied the fingerprints of licorice and processed licorice, the changing rules of the five bioactive constituents and the pharmacological activities of licorice during the processing procedure.By comparing the established HPLC fingerprints of licorice and honey-fried licorice, there was no obvious differences between the whole fingerprints of licorice and honey-fried licorice, but the peak areas and the peak number of honey-fried licorice generally decreased and the area percentages of some peaks had a dramatic change. The research also studied on the main different peaks of the two fingerprints. Five components including liquiritin apioside, liquiritin, licuraside, isoliquiritin and glycyrrhizic acid were isolated and identified by NMR analysis and compared with the reference data. Besides, licochalcone andβ-sitoterol have also been obtained during the research. Determination of active constituents of honey-fried licorice based on above results.In order to compare the content of active constituents of licorice with its processed products, HPLC method has been established to determinate the five active constituents, including liquiritin apioside, liquiritin, licuraside, isoliquiritin and glycyrrhizic acid in licorice and honey-fried licorice. The results showed that the contents of five main active constituents in honey-fried licorice were lower than that of licorice, which provides scientific evidences to the quality control of licorice and honey-fried licorice.The thesis also study the changing rules of the five active constituents by different processing conditions, including roasting temperature, roasting time and the content of added honey. The result showed that the contents of liquiritin, isoliquiritin and glycyrrhizic acid have been obviously changed when processed for 30min and above 130℃; the contents of flavonoids and glycyrrhizic acid have not been greatly changed after processed for 60min and 75min at 110℃. The comparison of HPLC fingerprints of honey-fried licorice by adding different content of honey showed that the contents of main constituents were decreasing while the honey percentage was increasing, but the percentage of each peak area was not changed dramatically.The analysis of the HPLC fingerprints of licorice and its three prepared products (honey-fried licorice, honey-mixed honey and dry-fried licorice) suggested that there were no obvious differences between above four fingerprints and the correlative coefficients of them were comparatively high. The distinctions were only existed in the peak area and the percentage of peak area; the influence factors of the main peak areas have also been discussed. Our study provides valuable references to the processing technology of licorice.Aiming at the different efficacy of the raw and processed licorice, comparative research has been applied to study the pharmacological activities of them, and three pharmacological experiments (enhancing immune function, relieving cough and eliminating phlegm) have been studied. The results show that the function of enhancing mice's immune of honey-fried licorice is better than licorice but the effect of cursing cough and removing phlegm is worse than it. Such result provided scientific backgrounds for the clinic use of licorice and honey-fried licorice. |
