Non-destructive analysis of glycyrrhizin in Ummaruekvati dispensatory Thai traditional medicine:(TJPS-2019-0198.R1)

Abstract

Ummaruekvati is an antitussive traditional medicine. It contains licorice as the main ingredient and the major chemical component is glycyrrhizin. The conventional method for quantitative analysis of glycyrrhizin content in licorice is by HPLC, which is destructive of the sample, time-consuming, high cost, and has many steps in the sample preparation process. In this study, a rapid and non-destructive near-infrared spectroscopy (NIR) method was applied for quantitative analysis of glycyrrhizin content in Ummaruekvati dispensatories. A partial least squares chemometric method with various data pre-treatments was performed to establish the calibration model. The best calibration model was obtained using baseline correction over the wavelengths of 1000-2500 nm with four principle components. It showed a high coefficient of determination (R2=0.9392), low root mean squared error of cross-validation (RMSECV=0.0532) and low standard error of calibration (SEC=0.0516). The average predicted results of glycyrrhizin content in five tested Ummaruekvati dispensatories was 91.74% with the %RSD of 11.49. The results showed that non-destructive NIR spectroscopic analysis combined with chemometrics can be used for routine quality control of glycyrrhizin content in Ummaruekvati dispensatories with advantages of reduced time with no sample preparation or sample loss.