Objective

2

Aiming at the residue of Shaoyao Gancaotang， the extraction， qualitative and quantitative study of the small molecule resource components were carried out to clarify the residual small molecule chemical components in the residue and explore the ways of its resource utilization.

Method

2

The ultra-performance liquid chromatography-quadrupole-time-of-flight tandem mass spectrometry （UPLC-QTOF-MS/MS） was used to qualitatively identify the residual small molecule substances in the dregs of Shaoyao Gancaotang. Agilent C

18

reversed-phase chromatographic column （3.0 mm×100 mm， 2.7 µm） was used at the flow rate of 0.4 mL·min

-1

， the injection volume was 5 µL， and the mobile phase was gradient eluted with 0.05% formic acid aqueous solution （A）-acetonitrile （B） （0-1 min， 14%-17.5%B； 1-3 min， 17.5%-19%B； 3-4 min， 19%-20%B； 4-5 min， 20%B； 5-6 min， 20%-21%B； 6-9 min， 21%B； 9-22 min， 21%-36%B； 22-23 min， 36%B； 23-32 min， 36%-43%B）， electrospray ionization （ESI） was employed with negative ion mode scanning and scanning range of

m

/

z

50-1 200. A high performance liquid chromatography （HPLC） was established for the quantitative analysis of its main components with Agilent C

18

reversed-phase chromatographic column （4.6 mm×150 mm， 5 µm）， the detection wavelength was set at 235 nm， the flow rate was 0.8 mL·min

-1

， and the injection volume was 5 µL. Mobile phase was 0.05% phosphoric acid （A）-acetonitrile （B） for gradient elution （0-1 min， 14%-19%B； 1-4 min， 19%B； 4-18 min， 19%-50%B）. The content changes of main components in the residue of Shaoyao Gancaotang were compared before and after two different techniques of organic solvent extraction and enzymatic extraction.

Result

2

A total of 16 chemical components in the residue of Shaoyao Gancaotang were qualitatively analyzed， and quantitative analysis found that there were many chemical components in the residue， among which the residues of 6 index components such as paeoniflorin and liquiritin reached more than 70% in the original decoction piece. After enzymolysis by cellulase， liquiritin in the residue could be converted into liquiritigenin. The content of crude polysaccharide in enzymatic extract of the residue was 6 times higher than that in the blank group， and the content was up to 12%.

Conclusion

2

There are still many small molecule resource components in the residue of Shaoyao Gancaotang， which has great development potential. Organic solvents can be used to re-extract the target components in the residue， and liquiritin can be converted into liquiritigenin by biological fermentation technology， and the crude polysaccharide from the residue can be extracted by enzymatic method to develop animal feed. This study can provide reference basis and approach for reusing the residues of Shaoyao Gancaotang preparations and dispensing granules， so as to realize the high-value utilization of Shaoyao Gancaotang.