Abstract: OBJECTIVE: To establish a quantitative model for the online analysis of hesperidin content in the extraction process of Huatan Qushi decoction for individuals with phlegm-dampness constitution by using near-infrared(NIR) spectroscopy and partial least squares(PLS) methods.METHODS: The reference content of hesperidin, an effective ingredient of Huatan Qushi decoction,was determined using high-performance liquid chromatography(HPLC). The modeling band was selected using synergy interval PLS(Si PLS) algorithms, and a PLS model demonstrating the relationship between NIR predictive values and HPLC reference values was established. The optimal modeling route was selected through global optimization of process trace parameters.RESULTS: The root mean square error of cross-validation was 9.8410. The coefficients of determination of the calibration set and prediction set were0.9860(R2 cal) and 0.9458(R_(cal)~2), respectively. The residual predictive deviation was 3.0115. The parameters demonstrated high predictive capability and reliability. The band was selected via the Si PLS method. There were seven latent variables.CONCLUSION: This study provides a favorable comprehensive evaluation method for variable selection and quality control of the Traditional Chinese Medicine extraction process.

Key words: Spectroscopy,near-infrared, Leastsquares analysis, Hesperidin, Phlegm dampness, Huatan Qushi decoction