ABSTRACT
Objective To establish a combined quality evaluation model of fingerprint and quantitative analysis of multi-components with a single-marker (QAMS) to analyze the total flavonoids from licorice residue by the chemical conversion method; To provide technical support for quality control in production. Methods Total flavonoids of breaking cell wall and enriching were taken as the object of study to establish fingerprint. With liquiritin as internal reference, the relative correction factors of isoliquiritin, glycyrrhizin, isoliquiritigenin and glycyrrhizic acid were established respectively, and the contents were determined. Meanwhile, the calculated values were compared with the measured value by external standard method to verify the practicability and stability of QAMS. Results The HPLC fingerprint of total flavonoids from licorice residue was established. 11 common peaks were identified, and 5 common peaks were identified, and the similarity of the 10 extracts was >0.99; the relative error between the calculated results of QAMS and the measured values of the external standard method was <4%; the RSD of relative correction factor calculated by the multiple concentration method was <2%. Conclusion The method is accurate, reliable, specific, and stable, with good repeatability, which can be used for the quality control of total flavonoids from licorice residue.
ABSTRACT
Objective To establish the quality standard of flavone extracts in licorice residue; To provide the methods and basis for the quality control of total flavonoids extracted from licorice residue.Methods TLC was applied to compare the extracts with liquiritin and licorice; UV-spectrophotometry was used to measure the content of total flavones; EDTA-2Na titration was used to determine the content of calciumion.Results In the chromatogram of the test product, the spots of the same color were displayed on the corresponding position of the control medicinal material, and the fluorescent spots of the same color were displayed on the corresponding position of the control product. UV-spectrophotometry showed glycyrrhizin had a good linear relationship in the range of 3.32–9.96 μg/mL (r=0.9997), the absorbance between 0.3 and 0.7. The average recovery rate was 102.41% (RSD=3.22%), and the average content of total flavonoids in three batches of flavonoids extract was 8.82%. The average content of calciumion was 0.107% (RSD=3.61%).Conclusion This method has good repeatability, high sensitivity and accurate results, and can be used for the quality control of flavonoids in licorice residue.