RÉSUMÉ
This study was aimed to analyze the content variations of chemical constituents produced in fresh Radix Rehmanniae (Xian-Di-Huang) after processing into Radix Rehmanniae Recens (Sheng-Di-Huang) and Radix Rehmanniae Preparata (Shu-Di-Huang). HPLC was used in the study of preparing Xian-Di-Huang into Sheng-Di-Huang, and the processing into Shu-Di-Huang. The contents of two newly produced chemical components, which were 2,3-dihydro-3,5-dihydroxy-6-methyl-4H-pyran-4-one (DDMP) and 5-hydryoxymethyl-furfural (5-HMF). The contents of both chemical components were determined in Sheng-Di-Huang and Shu-Di-Huang bought from the market. The Zorbax SB-C18 column (250 mm í 4.6 mm, 5 μm) was used. The mobile phase was methanol-wa-ter (5:95). The flow rate was 1.0 mL·min-1. The detection wavelength was set at 280 nm. The results showed that no DDMP or 5-HMF was detected in Xian-Di-Huang. However, after processing, DDMP and 5-HMF can be de-tected in both Sheng-Di-Huang and Shu-Di-Huang. The content in Shu-Di-Huang was higher than that in Sheng-Di-Huang. Both contents in Shu-Di-Huang were gradually increased along with processing time. The con-tent reached to the highest level after processing for 24 h and 32 h, respectively. And then, the content decreased. Both DDMP and 5-HMF were detected from three batches of Sheng-Di-Huang and ten batches of Shu-Di-Huang bought from the market. The content of 5-HMF was higher in Shu-Di-Huang than in Sheng-Di-Huang. There was no obvious difference in the content of DDMP between Sheng-Di-Huang and Shu-Di-Huang. It was concluded that DDMP and 5-HMF were produced in the processing Sheng-Di-Huang and Shu-Di-Huang. The contents were gradually increased along with the prolonging of processing time. There was obvious difference in the content of 5-HMF in Shu-Di-Huang and Sheng-Di-Huang.
RÉSUMÉ
Objective: To isolate the chemical constituents newly produced in processing of Polygonati Rhizoma and to analyze the content changes during its processing. Methods: Two new chemical constituents were isolated from the processed Polygonati Rhizoma by using chemical extraction and identified by LC-MS. Then HPLC analysis was performed to analyze the content changes of the two newly produced constituents in three species of wine-processed Polygonati Rhizoma during different processing periods. The contents of the two compounds in 15 batches of commercially available wine-processed Polygonati Rhizoma were determined. The HPLC was performed on a Zorbax SB-C18 column (250 mm × 4.6 mm, 5 μm) with methanol-water (8:92) as the mobile phase at 1.0 mL/min, detection wavelength was 280 nm, and column temperature at 45°C. Results: The newly produced chemical constituents were 2, 3-dihydro-3, 5-dihydroxy-6-methyl-4H-pyran-4-one (DDMP) and 5-hydryoxymethyl-furfural (5-HMF). The content of DDMP in Polygonatum cyrtonema increased to the top when processed to 24 h and then decreased. The content of 5-HMF was increased gradually throughout the processing. The two chemical constituents were found in the three kinds of wine-processed Polygonati Rhizoma. In the 15 batches of commercially available Polygonati Rhizoma, the range of DDMP in 13 batches was from 1.395% to 5.265%, and the range of 5-HMF in 14 batches was from 0.079% to 0.708%. Moreover, the contents of the two constituents in the three kinds of wine-processed Polygonati Rhizoma (16 h) were within the above ranges. Conclusion: The contents of the two chemical constituents in Polygonati Rhizoma change with the processing time. Therefore, these results could provide the basis for making the quality standard and defining the processing time endpoint of Polygonati Rhizoma.