ABSTRACT
Objective: A method was established to obtain fingerprint and determination of six components in Glycyrrhizae Radix et Rhizoma Pieces (GRRP) based on HPLC-PDA, and samples with four kinds of softening methods (showering moistening, steaming, 70 ℃ decompression steaming, 85 ℃ decompression steaming) were analyzed. Methods: The content of total flavonoids and total saponins was determined by ultraviolet spectrophotometry with liquiritin and glycyrrhizic acid as reference materials. Simultaneous determination of six components of liquiritin, ononin, isoliquiritin, glycyrrhizin, echinatin, glycyrrhizic acid was performed based on HPLC. Changes of the components content in the samples which treated by different softening methods were compared. The similarity evaluation of samples with different softening methods was carried out by the chromatographic fingerprint similarity evaluation system of traditional Chinese medicine, and cluster analysis was also carried out. Results: The results showed that the content of total flavonoids and total saponins in untreated samples was the highest, and the content of total flavonoids and total saponins in samples treated by showering moistening was the lowest. The three treatment methods of atmospheric pressure steaming, steaming decompression at 70 ℃ and steaming decompression at 85 ℃ had little effect on the samples. The content determination showed that the content of isoliquiritin was decreased significantly after softening treatment. The difference among the different softening treatment groups was not significant. The samples with different softening methods of the three batches of samples were grouped together with their raw products. Different softening methods had no significant difference in the composition of the medicinal herbs. Conclusion: The established method can quickly and accurately determine the six components, and in particular, the content of isoglycyrrhizin should be monitored. Combining production efficiency, production cost and quality evaluation, steaming is the most feasible in the production process. This study provided theoretical guidance for the large-scale production of softening, which was conducive to further standardizing the production process of GRRP.
ABSTRACT
Objective: To study the chemical constituents of flavonoids from Glycyrrhizae Radix et Rhizoma. Methods: The compounds were isolated and purified by column chromatography over HP-20 macroporous resin, silica gel, Sephadex LH-20, and preparative RP-HPLC. Their structures were elucidated by physicochemical properties and spectral analyses. Results: Ten flavonoids were isolated and identified as 4’,6,7-trihydroxy-2’-methoxyl-chalcone (1), 3’,4’,5,7-tetrahydroxy-8-(3-hydroxy-3- methylbutyl)-isoflavone (2), isoliquiritigenin (3), isoliquiritin (4), echinatin (5), orobol (6), ononin (7), 2(S)-3’,5’,7-trihydroxy- flavanone (8), 2(S)-naringenin-4’-O-β-D-glucopyranoside (9), and 4’,7-dihydroxyflavone (10). Conclusion: Compounds 1 and 2 are new compounds named isolicochalcone B and licoisoflavone G, while compound 9 is isolated from the genus for the first time.
ABSTRACT
Objective To develop a systematic chromatography separation method for flavonoids from Glycyrrhiza uralensis Fisch. (GU). Methods A new method for the separation of effective parts and monomers of flavonoids from GU by two-dimensional reversed-phase liquid chromatography was developed using the self-developed preparation chromatography plant system with independent intellectual property rights. Flavonoids compounds were enriched with specific adsorption materials. The separation conditions of the chromatography were optimized by the chromatographic separation expert system software, and the loading weight of samples and the enrichment times of a separation were investigated. Results The process of chromatography separation of flavonoids from GU had good precision and reproducibility with C18 as separation and enrichment solid phase and the methanol/water and acetonitrile/water as mobile phase of one-dimensional and two-dimensional chromatography system. The dilution solution which used for one-dimensional and two-dimensional enrichment chromatography was water. The flow rate of gradient elution and dilution enrichment solution was 21 mL/min. The sample loading amount of chromatography separation was 300 mg each time. A total of 16 flavonoids parts contained stable chemical composition were obtained by the repeatable separation method after three times of enrichment. Nine pure compounds were obtained and identified by NMR and MS, which were liquiritin, liquiritigenin, formononetin, echinatin, 7,4'-dihydroxyflavone, 4'-O-[β-D-apio-D-furanosyl-(1→2)-β-D-glucopyranosyl] liquiritigenin, isoliquiritigenin, glycyrol, and glycycoumarin. Conclusion The study can provide a certain reference value for the systematic separation and cognition for flavonoids from GU.
ABSTRACT
Objective: To study the chemical constituents in the roots of Astragalus membranaceus. Methods: The constituents were isolated and purified by silica gel, ODS, polyamide and Sephadex LH-20 column chromatography. Their structures were elucidated by NMR spectra. Results: Twenty-three compounds were isolated from the roots of A. membranaceus, covering 14 flavonoids, eight triterpenoid saponins and one phenylpropanoid. They were identified as 2'-methoxyisoliquiritigenin (1), echinatin (2), licochalcone B (3), 3', 4', 7-trihydroxyflavone (4), 4', 7-dihydroxyflavone (5), 3', 7, 8- trihydroxy-4'-methoxyisoflavone (6), 4-hydroxycinnamic acid (7), calycosin (8), formononetin (9), 2', 4, 4'-trihydroxychalcone (10), pendulone (11), liquiritigenin (12), pratensein (13), calycosin-7-O-β-D-glucopyranoside (14), ononin (15), astragaloside IV (16), cyclocanthoside E (17), isoastragaloside II (18), astragaloside II (19), astragaloside III (20), isoastragaloside I (21), brachyoside B (22), and cycloaraloside A (23). Conclusion: Compounds 1-7 are isolated from the plants of Astragalus Linn. for the first time.